The report is divided into the following five sections, each of which has a compiler or compilation group:
1.1 Geological Survey of Canada (W.Roest, M.Pilkington, P.Keating, M.Thomas, R.Bird, W.Miles, R.Dumont, J.Tod)
1.1.1 Aeromagnetic data processing and interpretation
Considerable efforts were spent in improving the quality of existing data sets, by developing further techniques for flight line decorrugation, survey to survey levelling and long-wavelength anomaly assessment. In addition to applying decorrugation filters, Keating (1997) developed a method to automatically reinforce trends between magnetic profiles, thus providing greater continuity of narrow anomalies. In the case where anomalies due to sources with varying trends, such as radiating dyke swarms, obscure other magnetic signatures of more direct interest, a coordinate projection scheme has been developed to remove such anomaly trends (Pilkington and Roest, 1998). This technique was successfully demonstrated on data collected over the Mackenzie dyke swarm in the Northwest Territories.
Historic high-altitude (~4 km) aeromagnetic data collected by the former Earth Physics Branch of the Department of Energy, Mines and Resources, in the early seventies were used to independently assess the intermediate-wavelength magnetic field over the Canadian landmass (Pilkington and Roest, 1996). They demonstrated, that despite navigational inaccuracies, the EPB data provides a reliable magnetic field in the wavelength band of 300-2000 km. When upward continued, the higher altitude data compare very well with satellite-derived magnetic anomalies (Ravat et al., 1997). Pilkington and Roest demonstrated that this type of high-altitude data can successfully be applied to the national aeromagnetic coverage, in order to improve its intermediate wavelength content. This opens the way for a continent-wide, high-altitude survey of longer wavelength magnetic anomalies, for which plans are being developed by a USGS-led steering committee (Hildenbrand et al., 1996).
The use of aeromagnetic data for basement mapping in sediment covered areas has been a focus of GSC scientists over the past few years. A series of interpreted Precambrian basement maps was produced for Saskatchewan (Miles et al., 1997) and will be combined with Manitoba (Pilkington et al. 1998) and Alberta, to provide insight into the tectonic framework of the Western Canada Sedimentary Basin.
1.1.2 Aeromagnetic Surveys
Over 630,000 line-km of aeromagnetic data have been collected by the Geological Survey of Canada (GSC) in collaboration with various industrial partners (Dumont et al., 1996; 1997a; 1998). Surveys were flown in a variety of geographic areas with numerous goals. High-resolution surveys of mining camps were flown over Sullivan, British Columbia and Bathurst, New Brunswick while data were collected in Victoria Island and in the Toodoggone area, B.C., for mineral exploration purposes. Oil and gas exploration has led to partnership surveys in the Yukon and the Mackenzie valley corridor, Northwest Territories, while GSC geologic mapping in Baffin Island was supported by two phases of data collection. Continuation of the Polar Margin Aeromagnetic Program led to surveys flown over the Lincoln Sea and northeast Ellesmere Island. A recently completed survey over Lake Ontario and northern New York will help in seismic risk studies for the nuclear energy industry.
Levelling of the National Aeromagnetic Database is complete except for the Arctic Islands. Survey data have been computationally draped to a datum 305 m above terrain and all levelling corrections applied to the original profile data (Dumont et al., 1997b).
1.1.3 Magnetic data compilation projects
The magnetic compilation of the North Atlantic and Arctic Oceans and surrounding landmass has successfully been completed with the publication of an extensive CD-ROM (Verhoef at al. 1996) and a series of open-file maps (Roest et al., 1996a,b). The documentation describes the many innovative techniques that were used to combine a large number of aeromagnetic and shipborne surveys of different vintage and quality. For example, the vast shipborne component of the database has successfully been used to extract a latitude dependent diurnal variation model for the oceanic regions, which is better able to remove the diurnal signature of the data than global spherical harmonic models. Such compilations, in conjunction with those from Russia and Australia, are now being used as extra constraints in paleoreconstructions of the Rodinian supercontinent. Continental-scale magnetic data sets are being used to investigate the validity of competing paleomagnetic and geologic reconstructions (Bird and Roest, 1998a,b).
The compilation of a new magnetic anomaly map and digital database
for the North American continent is in progress. The joint project between
the U.S. Geological Survey, Geological Survey of Canada and Consejo de
Recursos Minerales (Mexico) is expected to be complete in 2002. The products
(featuring a 1-km gridded data set) will supersede those produced in 1987
for the Decade of North American Geology project.
Bird, R.T., and Roest W.R., 1998, Testing the Rodinian supercontinent fit using continental potential field data: A new project, Geological Society of Australia, Abstracts No. 49, 38.
Dumont, R., Kiss, F., and Tod, J., 1998, Aeromagnetic survey program of the Geological Survey of Canada, 1997-1998; Geological Survey of Canada, Current Research, 1998; 75-77.
Dumont, R., Kiss, F., Stone, P.E., and Tod, J., 1997a, Aeromagnetic survey program of the Geological Survey of Canada, 1996-1997; Geological Survey of Canada, Current Research, 1997-D, 63-65.
Dumont, R., Pilkington, M. and Miles, W., 1997b, Levelling of aeromagnetic surveys in Canada: Proceedings of Exploration '97, Toronto.
Dumont, R., Kiss, F., Stone, P.E., and Tod, J., 1996, Aeromagnetic survey program of the Geological Survey of Canada, 1995-1996; Geological Survey of Canada, Current Research, 1996-D, 1996, 109-112.
Hildenbrand, T.G., Blakely, R.J., Hinze, W.J., Keller, R., Langel, R.A., Nabighian, M., and Roest, W.R., 1996, Aeromagnetic survey over US to advance geomagnetic research; EOS Trans. Amer. Geophys. Un., 77, 265/268.
Keating, P., 1997, Automated trend reinforcement of aeromagnetic data; Geophysical Prospecting 45, 521-534.
Miles, W., Stone, P.E., and Thomas, M.D., 1997, Magnetic and gravity maps with interpreted Precambrian basement, Saskatchewan; Geological Survey of Canada, Open File 3488.
Pilkington, M., and Roest, W.R., 1998, Removing varying directional trends in aeromagnetic data; Geophysics, Vol.63, 446-453.
Pilkington, M., Thomas, M.D., and Lajeunesse, D.E., 1998, Magnetic and gravity maps with interpreted Precambrian basement; Manitoba Mining and Minerals Convention '98, Winnipeg.
Pilkington, M., and Roest, W.R., 1996, An assessment of intermediate wavelength magnetic anomalies over Canada; Can. J. Earth Sci., Vol.33, 12-23.
Ravat, D., Pilkington, M., Whaler, K., and Roest, W.R., 1997, Reliable wavelengths in MAGSAT data determined from comparisons with high-altitude aeromagnetic data; EOS, 78, American Geophysical Union (AGU) Spring Meeting, Baltimore, MD.
Roest, W.R., Verhoef, J., and Macnab, R., 1996a, Magnetic Anomaly Map of the Arctic North of 64 N; Open File 3281.
Roest, W.R., Verhoef, J., and Macnab, R., 1996b, Magnetic Anomaly Map of the North Atlantic; Open File 3280.
Verhoef, J., Roest, W.R., Macnab, R., and Arkani-Hamed, J., 1996, Magnetic anomalies of the Arctic and North Atlantic Oceans and adjacent landmasses; CD-ROM and Report, GSC Open File 3215a/b.
2.1 Magnetic Observatories and Repeat Stations
The Geomagnetic Laboratory of the Geological Survey of Canada continues to operate a network of 13 magnetic observatories; one observatory, Mould Bay, was forced to close due to the decommissioning of the host weather station. All but one observatory operates the CANMOS system which enables near-real time data transmission via satellite. In 1998 Iqaluit, the newest observatory, was accepted as a full member of the INTERMAGNET network. Recent demands by researchers for fast-sample observatory data has lead to the upgrade of the CANMOS data collection platform to enable the recording of 1 Hz data.
The Canadian magnetic repeat station program has continued at a reduced level of operation during the past four years. A major initiative has been the publication of an IAGA guide on magnetic repeat station survey procedures.
2.2 Geomagnetic Effects on Technology
A major study was undertaken, in collaboration with the Canadian electric power industry, to assess geomagnetic hazard to power systems. This involved an analysis of the frequency content of magnetic field variations for different levels of magnetic activity and the construction of conductivity models for different parts of Canada. These were used to calculate the electric field produced during geomagnetic disturbances, which were used as input to power system models to determine the geomagnetically induced currents (GIC) throughout particular power systems. Combining these results with statistics of geomagnetic activity provided an assessment of the frequency of occurrence of high GIC levels in different parts of the each power system.
An international study is underway to investigate the effects of telluric currents on pipelines. This project is led by the GSC and involves pipeline companies in Canada, Norway, Sweden and Finland, as well as participation by the Space Weather Centre in Lund, Sweden and the Finnish Meteorological Institute. Multi-point recordings are being made of the pipeline potential fluctuations caused by telluric currents in order to map the spatial characteristics of the potential variations. These are being used to test model calculations of geomagnetic induction in pipelines which will be used as a design tool for pipeline protection systems.
Several investigations of satellite anomalies are being undertaken. These include the relationship between auroral zone activity and energetic electrons, which can cause deep dielectric charging of space craft, and a statistical study of the NGDC satellite anomaly base with emphasis on magnetic signatures.
2.3 Forecasting Magnetic Activity
In 1995, the Geomagnetic Laboratory introduced an automated short-term
forecasting service, based on an expert system approach. This service now
provides forecasts for the sub-auroral, auroral, and polar cap regions
every hour. The forecasts are available on the Internet, at www.geolab.nrcan.gc.ca
and via ftp. Warnings of magnetic storms are contained with the short-term
forecasts, as appropriate. Longer term forecasts, for up to 27 days ahead,
are issued at three-weekly intervals and are available at the same address
and via mail.
Boteler, D.H. and St.-Louis, B., 1996. Monitoring and study of the magnetic and electric fields occurring in Quebec during magnetic storms. Final Report of Hydro-Québec and GSC Joint Project.
Boteler, D.H., Boutilier, S., Wong, A.K., Bui-Van, Q., Hajogos, L., Swatek, D., Leonard, R., Hughes, B., Ferguson, I.J., Odwar, H.D., 1997. Geomagnetically induced currents: Geomagnetic hazard assessment, Phase II. GSC Open File No. 3420.
Boteler, D.H., 1997. Distributed source transmission line theory for active termination. Proc. 1997 EMC Symposium, Feb 18-20, URSI supplement 401-408.
Boteler, D.H. and Pirjola, R.J., 1997. Nature of the geoelectric field associated with GIC on long conductors such as power systems, pipelines and phone cables. Proc. Beijing EMC Symposium, 68-71.
Boteler, D.H. and Pirjola, R.J., 1998. The complex image method for calculating the magnetic and electric fields produced at the surface of the Earth by the auroral electrojet. Geophys. J. Int., 132, 31-40.
Boteler, D.H., Seager, W.H., Johansson, C., and Harde, C., 1998. Telluric current effects on long and short pipelines. Proc. CORROSION '98, NACE National Conference, San Diego, Ca.
Boteler, D.H. and Pirjola, R.J., 1998. Modelling geomagnetically induced currents produced by realistic and uniform magnetic fields. IEEE Trans. Power Delivery, 13, 1303-1308.
Boteler, D.H., 1998. The relation between magnetic range values and spectral power. Geophys. J. Int., 134, 613-616.
Boteler, D.H. and Seager, W.H., 1998. Telluric currents: A meeting of theory and observation. Corrosion, 54, 751-755.
Boteler, D.H., Pirjola, R.J. and Nevanlinna, H., 1998. The effects of geomagnetic disturbances in electrical systems at the Earth's surface. Advances in Space Research, 22, 17-27.
Boteler, D.H., 1998. Geomagnetic effects on electrical systems. Physics in Canada, 5, 332-337.
Boteler, D.H. and Pirjola, R.J., 1999. Calculating the magnetic and electric fields produced by a line current above the earth. Proc. Zurich Electromagnetic Compatibility Symposium, Feb, 1999, 237-242.
Boteler, D.H. and Jansen van Beek, G., 1999. August 4, 1972 revisited: A new look at the geomagnetic disturbance that caused the L4 cable system outage. Geophys. Res. Lett., 26, 577-580.
Boteler, D.H., 1999. Calculating the voltages induced in technological systems during a geomagnetic disturbance. IEEE Trans. EMC, in press.
Boteler, D.H., 1999., Geomagnetic effects on the pipe-to-soil potentials of a continental pipeline. Advances in Space Research, in press.
Bolduc, L., Langlois, P. Boteler, D., Pirjola, R., 1998. A study of geoelectromagnetic disturbances in Quebec, 1. General results. IEEE Trans. Power Delivery, 13, 1251-1256.
Bolduc, L., Langlois, P. Boteler, D., Pirjola, R., 1999. A study of geoelectromagnetic disturbances in Quebec, 2. Analysis of a large event. IEEE Trans. Power Delivery, in press.
Coles, R.L. and Lam, H.-L., 1998. Geomagnetic Forecasting in Canada: A review. Physics in Canada, 54, 327-331.
Golovkov, V.P. and Newitt, L.R., 1997. An evaluation of a regional orthogonal field model for Canada with respect to the Canadian geomagnetic reference field. J. Geomag. Geoelectr., 49, 337-346.
Haines, G.V. and Newitt, L.R., The Canadian geomagnetic reference field 2000. J. Geomag. Geoelectr., 49, 317-336.
Lam, H.-L., 1996. Forecast verification a RWC Ottawa. The Proceedings of the Evaluatiion of Space Weather Forecasts Workshop, Boulder, 165-170.
Lam, H.-L., 1997. Verification of 27 day three-zone geomagnetic forecast. Solar Terrestrial Prediction Workshop Proceedings, Hitichi City, Japan, 315-322.
Lam, H.-L. and Coles, R.L, 1997. Geomagnetic forecast at RWC Ottawa. Solar Terrestrial Prediction Workshop Proceedings, Hitichi City, Japan, 54-56.
Newitt, L.R. and Barton, 1996. The position of the north magnetic pole in 1994. J. Geomag. Geolectr., 48, 221-232.
Newitt, L.R., Barton, C.E. and Bitterly, J., 1996. Guide for magnetic repeat station surveys, IAGA, 126 p.
Pirjola, R., Viljanen, A. and Boteler, D.H., 1999. Series expansions for the electric and magnetic fields produced by a line or sheet current source above a layered earth. Radio Science, 34, 169-280.
Pirjola, R., Viljanen, A. and Boteler, D.H., 1999. Elecric field at the seafloor due to a two-dimensional ionospheric current. Geophys. J. Int., in press.
3.1 University of Toronto Seafloor EM group (N. Edwards)
My group has developed the towed, transient, coaxial magnetic dipole-dipole EM system for both shallow sea and deep ocean exploration and the above paper is the latest in a series of reports on experiments. We describe the apparatus and method of measuring the near surface electrical conductivity in the uppermost 20 m of sediment by analysing the magnetic signal transmitted from a source coil to a receiver coil towed continuously at about 2 knots over the seafloor. We show the conductivity in a deeply sedimented axial valley at the northern end of the Juan de Fuca ridge is strongly correlated with heat flow measurements. We analyse its variation in terms of fluctuations in temperature and porosity. The importance of the research is that it offers a very rapid method of identifying hydrothermal activity and possible sulphide deposition in the subjacent crust. Towed systems of this type that provide seafloor data systematically along survey lines, like the airborne EM system, are now contracted for geotechnical surveys. All have their origin in novel work at Toronto University.
We support our experimental studies with numerical experiments using both finite element and finite difference methodology. Jianwen Yang's thesis stemmed from conversations with Ed Sudicky (Univ. Waterloo). The WCGR group developed software for fluid and contaminant transport in fractured porous media. The equations for heat and fluid transport are rather similar and, with their aid, we adapted the software for studying the oceanic crustal environment. The paper listed demonstrates the importance of fracturing in the ocean crust in controlling the mechanism of heat transport. Small fractures can induce convection in environments which are normally conductive. The work is very important - it received excellent reviews. We were able to explain lateral perturbations in heat flow measurements observed in Middle Valley without specifying high, abnormal permeabilities in the basalt or basement undulations.
3.2 University of Manitoba (Ian Ferguson, K. Stevens, X. Wu, and V. Maris)
Electromagnetic (EM) research at the University of Manitoba has included participation in lithospheric studies and small-scale geotechnical and environmental studies. We have continued the analysis of magnetotelluric data from the LITHOPROBE Trans Hudson Orogen Transect, studying a conductor hosted in mid-crustal amphibolite grade rocks in western Manitoba, a complex geological region in eastern Saskatchewan, and the margin between the Proterozoic Trans Hudson Orogen and the Archean Superior Province. We participated in the LITHOPROBE SNORCLE Transect magnetotelluric survey and are presently analyzing data from Proterozoic terranes bordering the Archean Slave Province. We also participated in the 1997 and 1998 magnetotelluric surveys of the Archean western Superior province. A review of large-scale EM surveys in Canada was completed as a contribution to a GIC study. In smaller-scale surveys we have used time-domain EM soundings to examine groundwater salinity and fracture salinity in the upper 500 m of the Precambrian shield, DC-resistivity to monitor the Winter freezing of soil, and a variety of EM methods to map saline contamination, palaeokarst topography, and kaolinite deposits.
3.3 Geological Survey of Canada (A.G. Jones, X. Garcia, J. Ledo, J.A. Craven, D.E. Boerner, R.D. Kurtz)
3.3.1 Lithoprobe SNORCLE Transect activities (Jones)
3.3.1.1 Corridor 1 MT data acquisition (with I.J. Ferguson of U. Manitoba)
In 1996 contract MT measurements were made at sixty locations from the Archean Slave Craton, in Canada's north, to the deformation front of the Canadian Rockies. In addition, at each location very low frequency MT measurements were made using the GSC's long period magnetometer systems (LiMS). The low frequency response estimates from the contractor's equipment were in error due to coil calibration problems. These were rectified, after exhaustive forensic work identified the cause of the problem, and corrected estimates were delivered in early 1999.
3.3.1.2 Winter road acquisition
Innovative MT data acquisition took place along the 600-km-long ice road running north from Yellowknife to Contwoyto Lake took place in the winters of 1998 and 1999. The electrodes were lowered to the bottoms of the lakes through holes in the ice, whereas the magnetic fields were recorded by sensors on the shorelines.
3.3.1.3 Lake bottom measurements (with A.D. Chave and R. Evans of Woods Hole Oceanogrpahic Institution)
An array of 10 sites is currently recording across the whole of the Slave craton using EM instruments designed for use on the continental shelf, installed on the bottoms of lakes. The sites were installed in July 1998, and will be retrieved in July 1999. The 10 will then be re-deployed in 10 other lakes for a year from August 1999 onwards. This experiment will give broad, but coarse, coverage across the whole of the Slave craton.
3.3.2 Lithoprobe Trans-Hudson Orogen Transect (Jones, Ledo, Garcia, with I.J. Ferguson of U. Manitoba)
Work continued on interpreting the MT data from the Paleoproterozoic Trans-Hudson Orogen. A final overview paper is in preparation.
3.3.3 Lithoprobe Alberta Basement Transect (Craven, Boerner, Kurtz)
MT acquisition completed: 97 LIMS sites in 1995 and 91 LIMS sites in 1996. Collaborative work with F.W. Jones, University of Alberta and Gerry Ross, GSC Calgary. Papers published in Geology, Journal of Geophysical Research, Canadian Journal of Earth Sciences, and Science present images of foredeep facies, electrical anisotropy, and upper mantle metasomatism that characterize portions of the PaleoProterozoic East Alberta Orogen. Synthesis papers are 'in prep'.
3.3.4 Lithoprobe West Superior Transect (Craven, Boerner, Kurtz)
Reconnaissance and first phase of MT data acquistion completed. Thirty reconnaisance LIMS sites collected in Sept. & Oct. 1997; 128 sites in May-Oct 1998. Collaborative acquisition with Ian Ferguson at University of Manitoba and Dick Bailey at University of Toronto. Preliminary study of the data reveals a strongly conductive, layered, lithosphere beneath the North Caribou block in contrast to two-dimensional lithosphere associated with younger subprovinces to the south.
3.3.5 Lithoprobe Abitbi-Grenville Transect (Boerner, Kurtz)
Synthesis paper accepted for publication in Canadian Journal of Earth Sciences. MT impedance data available on companion CD-ROM.
3.3.6 Collaborative work with Falconbridge Ltd. (Craven)
Twenty-three AMT/MT sites collected during 1995 and 1996 within the Cobalt Embayment reveal a shallow linear conductive feature spatially associated with previous seismic evidence for Nipissing diabase intrusions and the Temagami Lake Magnetic Anomaly. Information outside of non-disclosure period is available in the SEG 1998 Expanded Abstracts.
3.3.7 MT for mining-scale problems (Jones, Garcia)
Under a jointly-sponsored industrial fellowship, Dr. X. Garcia is investigating methods for improving the utility of MT for addressing problems at the mining-scale.
3.3.8 Tibet (Jones, with M.J. Unsworth of U. Washington and other membes of the INDEPTH Consortium)
Under the auspices of the multinational INDEPTH program (U.S.A., China, Germany and Canada), MT measurements were undertaken in Tibet during the summers of 1995, 1998 and 1999 to image the downgoing Indian plate beneath the Tibetan plateau.
3.3.9 Southern Appalachians (Jones, with Y. Ogawa of GSJ, P. Wannamaker of U. Utah, and M. Unsworth of U. Washington)
Analysis and modelling is continuing of the land and ocean MT data from the southern Appalachians.
3.4 Industrial activities
3.4.1 Geosystem Canada
Geosystem has carried out AMT surveys for massive sulfide exploration in Manitoba, Ontario, and Labrador. Over the last three years, this has lead to a progressive improvement in acquisition, processing, and interpretation techniques. Light-weight 24-bit GPS-synchronized systems are now deployed, and significant advances in robust processing (Larsen et al., 1996) have shown that good quality data in the band 1-1000Hz can be collected at all times of the day and with a recording duration of 10 minutes or less. This therefore puts AMT for deep mining exploration on an economic basis comparable with large-loop TEM. Interpretation has advanced significantly with the routine use of 2D inversion codes (Mackie and Rodi, 1998). The growth of field experience has demonstrated that responses over known ore bodies are far greater than 3D models predict, probably because conductive targets are associated with weak regional-scale 2D conductors (such as ultramafics with a few % of sulfides, graphites, etc.). Qualitative interpretation using mapped parameters such as impedance phase at a constant frequency is a surprisingly effective technique, albeit one which requires fairly dense data coverage.
3.5 University of Victoria (J.T Weaver, A.K. Agarwal)
At the University of Victoria, Dr. J. T. Weaver and Research Associate Dr. A. K. Agarwal have continued to develop methods for solving three-dimensional problems in geo-electromagnetic induction using finite differences on both staggered and non-staggered grids. Numerical solution on a non-staggered grid was stabilized by introducing an extra but identically vanishing term into the usual differential equation for the magnetic field. Other work has involved investigations of two-dimensional inversion problems and studies of the properties of the magnetotelluric impedance tensor.
3.6 University of British Columbia (D. Oldenburg and colleagues)
Between 1995 and 1999, scientists at the UBC Geophysical Inversion
Facility (UBC-GIF) have continued to carry out research on the theory and
application of linear and nonlinear inversion methodologies for geophysical
electromagnetic data. We include in this category low-frequency electromagnetics
which encompasses DC resistivity surveys and induced polarization. Mineral
exploration problems have been the primary application focus, but the methods
have been applied to environmental and engineering problems and they can
be applied to larger scale (MT) problems. For 1D problems we can now recover
either, or both of, the electrical conductivity and magnetic susceptibility
from frequency domain loop-loop data. The model norms are such that either
blocky or smooth models can be obtained. We are also able to invert CSAMT
data measured in the near-field, transition zone, or far field. In time-domain
surveys we can recover a 1D conductivity from surface measurements of the
magnetic field or its derivative. In 3D problems we have shown that, with
AIM updates, it is possible to generate an approximate conductivity model
by carrying out only a few forward modellings. Finally, the computations
in the inversion can be reduced by using approximate sensitivities.
Agarwal, A.K.,& Weaver, J.T., 1997. Two-dimensional inversion of Papua New Guinea data using "least-blocked" models. J. Geomag. Geoelec. 49, 827-842.
Boerner, D.E., Kurtz, R.D., Craven, J.A., Rondenay, S. and Qian, W., 1995. A buried Proterozoic foredeep under the Western Canada Basin? Geology, 23, 297-300.
Boerner, D.E., Kurtz, R.D. and Craven, J.A., 1996. Electrical conductivity and Paleo-Proterozoic foredeeps. Journal of Geophysical Research, 101, 13,775-13,791.
Boerner, D.E., Craven, J.A., Kurtz, R.D, Ross, G.M., and Jones, F.W.., 1998. The Great Falls Tectonic Zone: suture or intracontinental shear zone? Canadian Journal of Earth Sciences, 35, 175-183.
Boerner, D.E., Kurtz, R.D., Craven, J.A., Ross, G.M., Jones, F.W., and Davis, W.J., 1999. Electrical conductivity in the Precambrian lithosphere of western Canada. Science, 283, 668-670.
Boerner, D.E., Kurtz, R.D., and Craven, J.A., 1999. A summary of electromagnetic studies on the Abitibi-Grenville Transect. Canadian Journal of Earth Sciences, accepted for publication.
Cairns, R. Evans and R.N. Edwards, A time domain electromagnetic survey of the TAG hydrothermal mound. Geophys. Res. Lett., invited paper, 23, 3455-3458, 1996.
Chave, A.D. and Jones, A.G., 1997 Electric and magnetic field distortion decomposition of BC87 data. J. Geomagn. Geoelectr., 49, 767-789.
Chen, L., J.R. Booker, A.G. Jones, N. Wu, M. Unsworth, W. Wei and H. Tan, 1996 Electrically conductive crust in southern Tibet from INDEPTH magnetotelluric surveying Science, 274, 1694-1696.
Cook, F.A. and Jones, A.G., 1995. Seismic reflections and electrical conductivity: A case of Holmes' curious dog? Geology, 23, 141-144.
Craven, J.A., Boerner, D.E., Kurtz, R.D., Stevens, K., Watts, A., 1998. Magnetotelluric and 2-D seismic investigation over the Temagami Lake Magnetic Anomaly, 68th Annual Internat. Mtg., Soc. Expl. Geophys., Expanded Abstracts.
Craven, J.A., 1998. The magnetotelluric response of electrically dispersive orebodies. 68th Annual Internat. Mtg., Soc. Expl. Geophys., Expanded Abstracts.
R.N. Edwards, On the resource evaluation of marine gas hydrate deposits using a seafloor transient electric dipole-dipole method. Geophysics, 62, 63-74, 1997.
Ellis, R.G. (1995), "Joint 3D EM Inversion", Proceedings of the International Symposium on Three-Dimensional Electromagnetics, Schlumberger-Doll Research, Ridgefield, Connecticut, USA.,
Farquharson C.G., and Oldenburg D.W. (1996), "Approximate sensitivities for the electromagnetic inverse problem", Geophysical Journal International, 126, 235-252
Farquharson, C.G., Oldenburg, D.W., and Li, Y. (1998), "An Approximate Inversion Procedure for Lines/Grids/Collections of Time-domain Electromagnetic Soundings", Symposium on the Application of Geophysics for Engineering and Environmental Problems, 1998, 145
Ferguson, I.J., Jones, A.G., Yu Sheng, Wu, X., & Shiozaki, I., 1999. Geoelectric response and crustal electrical-conductivity structure of the Flin Flon Belt, Trans-Hudson Orogen, Canada, Can J. Earth Sci. (accepted).
Ferguson, I.J., & Desrosiers, G.A.J., 1998. Monitoring Winter freezing in a silt soil in southern Manitoba, Canada using surface DC resistivity soundings, J. Env. Eng. Geophys., 49-61.
I.J. Ferguson and R.N.Edwards, `Geophysical analysis of a magnetic storm recording on the Juan de Fuca Ridge.' Geophysical Journal International, final review.
Ferguson, I.J., Ristau, J.P., Maris, V.G., & Hosain, I., 1998. Geophysical imaging of a kaolinite deposit at Sylvan, Manitoba, Canada, J. Appl. Geophys., 41, 105-129.
Ferguson, I.J., Taylor, W.J. & Schmigel, K.S., 1996. Electromagnetic mapping of saline contamination at an active brine pit, Can. Geotech. J., 33, 309-333.
Ferguson, I.J. & Odwar, H.D., 1998. Review of conductivity soundings in Canada. Appendix 3 In Geomagnetically induced currents: Geomagnetic Hazard Assessment Phase II, Final Report, D.H. Boteler, Boutilier, S., Swatek, D., Bui- Van, Q., Leonard, R., Hughes B, Hajagos, L., Ferguson, I.J., & Odwar, H.D., Geological Survey of Canada and Canadian Electrical Association, 121 pp.
Garcia, X., A.D. Chave and A.G. Jones, 1997 Robust processing of magnetotelluric data from the auroral zone. J. Geomagn. Geoelectr., 49, 1451-1468.
Gupta, J.C. and Jones, A.G., 1995. Electrical conductivity structure of the Purcell Anticlinorium in southeast British Columbia and northwest Montana. Can. J. Earth Sc., 32, 1564-1583.
Marion Jegen and R.N. Edwards, `The electrical properties of a two-dimensional conductive zone under the Juan de Fuca Ridge', Geophys. Res. Lett., 19, 3647-3651, 1998.
Jones, A.G. and Gough, D.I., 1995. Electromagnetic images of crustal structures in southern and central Canadian Cordillera. Can. J. Earth Sc., 32, 1541-1563.
Jones, A.G., Eaton, D.W., White, D., Bostock, M., Mareschal, M. and Cassidy, J., 1996 Geophysical measurements for lithospheric parameters. In: Searching for Diamonds in Canada, A.N. LeCheminant, R.N.W. DiLabio, and K.A. Richardson (ed.), Geological Survey of Canada, Open File 3228, 243-250.
Jones, A.G. and K. Holliger, 1997 Spectral analysis of the KTB sonic and density logs using robust nonparametric methods. J. Geophys. Res., 102, 18,391-18,403.
Jones, A.G. and A. Schultz, 1997 Introduction to MT-DIW2 Special Issue. J. Geomagn. Geoelectr., 49, 727-737.
Jones, A.G., T.J. Katsube, and P. Schwann, 1997. The longest conductivity anomaly in the world explained: sulphides in fold hinges causing very high electrical anisotropy. J. Geomagn. Geoelectr., 49, 1619-1629.
Jones, A.G., 1998. Waves of the future: Superior inferences from collocated seismic and electromagnetic experiments. Tectonophys., 286, 273-298.
Jones, A.G., 1998. Imaging the continental upper mantle using electromagnetic methods. Lithos, in press.
Jones, A.G. G.W. McNeice, T. Korja, J.A. Craven, J.A. Wright and R.G. Ellis, 1998. Geoelectric image of a deep fault - the Dover fault, Newfoundland. Can. J. Earth Sci., submitted.
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Department of Earth Science, Memorial University, St. John's, Newfoundland
(J.P. Hodych, G.S. Murthy)
A.) ROCK MAGNETIC STUDIES: These concentrated on how magnetic anisotropy can be used to detect and correct for paleomagnetic inclination shallowing induced by compaction in fine-grained sediments (Hodych, et al. 1999). Studies of how low temperature demagnetization and variation of hysteresis can be used to infer domain state and controls on remanence retention were extended to magnetite-bearing rocks of high coercivity (Hodych, 1996; Hodych et al. 1998). G.S. Murthy has been studying the magnetic properties of the Voisey's Bay massive sulphides.
B.) PALEOMAGNETIC STUDIES: These concentrated on the history of the Iapetus Ocean. The 550 Ma Skinner Cove Volcanics of western Newfoundland were shown to carry a primary remanence suggesting North America had moved rapidly northwards between 577 and 550 Ma, perhaps signaling rapid opening of the Iapetus Ocean (McCausland and Hodych 1998). Paleomagnetism of the Cape St. Mary's sills of the Avalon Peninsula supported a narrow Iapetus by 440 Ma (Hodych and Buchan 1998). G.S. Murthy has continued paleomagnetic study of late Precambrian dykes and flows of southern Labrador.
Department of Earth Sciences, University of Ottawa (K. Benn)
Research over the last four years has concentrated on the use of the magnetic anisotropies, in conjunction with other Structural Geology and Geophysical techniques, in order to study mechanisms of pluton emplacement and batholith construction. The magnetic anisotopies are used to systematically map mineral preferred orientations in granitoid rocks. Benn has set up an analog Tectonics modeling lab and is currently using it to study syntectonic pluton emplacement. He is also working on the spatial association of seismicity with faults east of Lake Ontario, and he is supervising research on the Structural Geology of mineral deposits.
Continental Science Division, Geological Survey of Canada, Ottawa
(K.L. Buchan, R.E. Ernst, J.K. Park)
Integrated studies of paleomagnetism and U-Pb geochronology have been carried out on a number of mafic dyke swarms from the Canadian Shield and Anabar Shield of Siberia with the aim of establishing precisely dated paleomagnetic poles. Such data are critical to establishing reliable Precambrian polar wander paths and testing paleocontinental reconstructions. Paleomagnetic studies in the Mackenzie Mountains of the Yukon have improved the Neoproterozoic polar wander path for Laurentia. Magnetostratigraphic studies in Carboniferous redbeds of Nova Scotia have helped to better constrain the base of the Kiaman Magnetic Superchron. Measurement of anisotropy of magnetic susceptibility is being applied to the mapping of flow directions in mafic dyke swarms and sill provinces. These studies suggest dominantly lateral flow in giant swarms, except in the proximity of their mantle plume sources.
Department of Physics, University of Toronto (D.J. Dunlop, O.Ozdemir, S.Xu, Y.J. Yu)
Our group's work over the past four years has been in a number of different areas: domain structure observations in magnetite; micromagnetic calculations of domain structures and hysteresis; grain-size dependence of magnetic properties like thermoremanence (TRM), anhysteretic remanence (ARM) and susceptibility compared to theoretical predictions; low-temperature magnetic properties and low-temperature demagnetization (LTD) of magnetite; theory of the Lowrie-Fuller test and of the Day et al. diagram; orogenic uplift magnetizations and paleothermometry in the Sydney Basin, Australia; possible differences in the time of post-orogenic magnetization of different lithotectonic domains in the Grenville Province, Ontario; self-reversing TRM in dacitic and andesitic pumices from Japan; and archeomagnetism of Ontario aboriginal sites with radiocarbon dates from AD 90 to 1640. Two of us also published a major textbook on rock magnetism in 1997.
Department of Geology, University of Toronto (H.C. Halls)
A regional paleomagnetic study of the 2.45 Ga Matachewan dyke swarmin eastern Ontario has sampled more than 400 dykes over an area of about 250,000 km within and bordering the 2 Ga Kapuskasing Zone (KZ). It was previously established that a single magnetic field reversal from R to N characterises the period from about 2445 to 2473 Ma which represents the duration of magmatism. Furthermore where the crust has been uplifted, as within the KZ, the dykes have N polarity, but outside in shallower crust, they have R. This polarity pattern has been used to map a previously unknown segment of the Kapuskasing zone. In addition, the deeper crustal roots of dykes show a more intense clouding of their feldspar. It has been shown that this is due to sub-microscopic magnetite precipitated within the feldspar, as a result of slow cooling at ambient deep crustal temperatures. Rock magnetic and paleomagnetic experiments on feldspar separates (Zhang, Ph. D. thesis, 1999) show that that the magnetite carries an N Matachewan remanence. Since the rate of apw during Matachewan magmatism is known, it can be estimated that the remanence and therefore the magnetite exsolution, occurred no more than 1-2 million years after the dykes were intruded. The use of the lateral variations of magnetic polarity and feldspar clouding intensity across a dyke swarm to map broad crustal deformation of a shield region represents a novel method which in principle can be applied to other shield areas in the world, most of which have abundant Proterozoic dyke swarms. It also represents an important means to map the third (depth) dimension of a dyke swarm, and represents the first time that changes, as a function of crustal depth, in the magnetic and feldspar ty studies in particular have identified a major south-verging thrust fault that bounds the southern margin of the Mamainse Point volcanics. This fault which can be followed across much of Lake Superior from aeromagnetic data, may link up with the Keweenaw fault, the southerly of the two major bounding faults of the Mid-Continent Rift. Likewise the northern bounding fault through Michipicoten Island also has a potential counterpart on the Ontario mainland. The pop-up structure defined by these faults may join with the Kapuskasing structure thus defining a long-lived (from 0.9 to 2 Ga) zone of crustal uplift extending from James Bay to the US mid-continent.
Department of Geology, McMaster University, Hamilton, Ontario (W.A.Morris)
Geophysics applied to ore body detection and delineation problems. Magnetic, electrical and gravity surveys to identify ore body location (Sudbury, Hemlo) Measurement and interpretation of physical rock property variations to constrain geophysical models (magnetics, density, radiometrics, resistivity) Borehole hole geophysics specifically three-component vector magnetic, radiometric, and resistivity surveys. Borehole navigation. Application of potential field and remote sensing techniques for the detection of surface oil seepages. Application of paleomagnetic techniques for locating regions of fluid flow related to mineral deposits, and oil pools.
Department of Earth Sciences, University of Western Ontario, London, Ontario
(H.C.Palmer)
My research employs paleomagnetic data to assess the presence or absence of vertical axis rotations in disrupted ashflow tuff units in the Basin and Range Province of the western United States. Anisotropy of magnetic susceptibility (AMS) is employed as a rapid method of petrofabric analysis which is used to interpret flow directions in these tuff sheets to infer source vent locations. Specific projects include the Caetano Tuff (with co-workers .S. Gromme and W.D. MacDonald) and various members of the NE Nevada Volcanic Field.
The AMS of the Nipissing Sills is being studied (with co-workers R.E. Ernst and K.L. Buchan, G.S.C) with the view to determining whether the sills were fed from local subjacent magma chambers or from the distal time-equivalent Senneterre dykes.
Earth Sciences, University of Windsor (D.T.A. Symons)
1) Dating of ore deposits that are not amenable to radiometric age dating to better understand their genesis - Robb Lake and Kicking Horse MVT deposits in Canada; East Tennessee, Central Tennessee and Viburnum Trend MVT deposits in the U.S.A.; Navan Zn-Pb in Ireland; and work continues on a variety of other deposits including zinc-lead, fluorospar, bauxite and iron (M.T. Lewchuk, Ph.D; M.T. Smethurst, M.Sc.; K.K. Stratakos, B.Sc.; J.H.Ashton, Outokumpu Tara Mines Ltd.; D.R. Boyle, GSC; L. Fontboté, Univ. Geneva; D.L. Leach, USGS; C.G. Rodrigues, Univ. Windsor; D.F. Sangster, GSC)
2) Dating of dolomitization in petroleum reservoir rocks using core from the Western Canada Sedimentary Basin. Petrologic, geochemical and isotope analyses are being done concurrently. Six reservoirs have been studied and the results are being published. Further work is underway (J.S. Lonnee, M.Sc.; M.T. Cioppa, PDF; M.T. Lewchuk, PDF; I.S. Al-Aasm, Univ. Windsor; K.P. Gillen, Vox Terrae Intl.)
3) Geotectonic assembly of the accreted terranes of the Canadian Cordillera in northern British Columbia and the Yukon. Most of this work has been directed towards plutons in the Stikine and Yukon - Tanana terranes using geobarometric methods to determine paleohorizontal (M.J. Harris, Ph.D.; P.J.A. McCausland, Ph.D.; W.H. Blackburn, Univ. Windsor; C.J.R. Hart, Yukon Geology Program)
4) Geotectonic analysis of the assembly of the Trans-Hudson orogen in Manitoba and Saskatchewan. Again most of this work has been done on plutons and is nearing completion. They provide the classic paleomagnetic signature for continent-continent collision followed by a hairpin and stillstand in the apparent polar wander path (M. Gala, Ph.D.; C.D. Mackay, B.Sc.; S.P. Radigan, B.Sc.; M.J. Harris, PDF; H.C. Palmer, Univ. Western Ontario; D.C. Peck, Manitoba Energy and Mines)
Department of Geology, Lakehead University, Thunder Bay, Ontario
(G.J. Borradaile)
Principal current projects include:(a) Effects of experimental stress and strain on remagnetization. This includes standard triaxial tests as well as those using split cylider-specimens that permit transpressive or "simple" shear to be applied. Published results so far reveal that very short stress pulses can remagnetize both soft and hard remanence components as well as permanently changing the coercivity spectrum. (b) Effects of experimental strain in the production of magnetic anisotropy (AMS). Previous studies examined the effects on materials with dilute magnetite contents, and the effects of conducticity anisotropy (ACMS) in pyrrhotite-rich samples. Now strain-alignments on dilute pyrrhotite-content samples reveal much more complex relationships (collaboration with post-doc. Ph. Robion). (c) Magnetic properties of tektites (colaboration with post-doc. T. Werner). Preliminary results show that extreme homogeneity of tectite magnetic properties from different strewn-fields (excepting Moldavia), and within the huge Australasian strewn field. We attribute this to very rapid quenching of vaporized sedimentary protolith on its fall back through the atmosphere. Quenching was so rapid that the samples have no detectable iron oxides, and thus no remanence. (d) Anisotropy of low field susceptibility (AMS) and of anhysteretic remanence (AARM) combined with observations on the progressive deflection of syntectonic/syn-exhumation remanences have shed new light on the evolution of the Kapuskasing Structural Zone, and on the Rainy Lake Anorthosites of Northern Ontario. Preliminary results on both projects have appeared in Tectonophysics. (e) Previously the combined "averaged orientation distribution" of all minerals was identified by AMS. Subsequently, AARM permitted us to isolate the contribution of the remanence-bearing minerals to the fabric. Now, using sedimentary rocks, with simple petrofabric, we have been able to isolate the paramagnetic contribution by tensor subtraction of normalized AMS/AARM data. Preliminary results have been published. (f) Studies of VRM that has unusually high stability in limestones provides a useful VRM-clock that monitors the reorientation of limestone on an archeological or geomorphological time-scale. Calibrating the scales with ancient monuments of known age (in Europe and the Near East) we have now developed the longest "experiments" in VRM acquisition (or remagnetization) lasting 4,000 years. Recent samples provided by an Archeological group may extend this VRM acquisition scale back 7,500 years. The method has been of some amusement to archeologists, featuring in the popular scientific Press and on Discovery and BBC TV programs. However, I believe the applications to geomorphology are of more practical significance, for example dating landslides in Eastern England to 1,800 years ago, with "steady" rotation of slump blocks through this period at about 0.2 degrees of arc. (g) Combined AMS, AARM studies of the Troodos ophiolite in Cyprus have revealed new information on flow patterns and conditions in the suboceanic asthenosphere . (h) AMS and AARM studies of the pelagic limestone cover of the Troodos complex have added extra information to the neotectonic development of Cyprus.
Institute for Geophysical Research, University of Alberta (M.E. Evans,J.F. Lerbekmo)
Magnetoclimatological studies form the central core of the work being carried out at the Paleomagnetic Laboratory in Edmonton. In addition to the classic Chinese sites, we are also investigating samples from the Czech Republic and Siberia. Most of this work is collaborative (F.Heller, ETH, Zurich; N.W.Rutter, Department of Earth and Atmospheric Sciences, University of Alberta; Z.L.Ding, T.S.Liu and J.M.Han, Academica Sinica, Beijing; L.P.Yue, Northwestern University, Xian; D.G.Rancourt, Physics Dept., University of Ottawa) and much of it has now been published (see bibliography for details). The Siberian work formed the basis of a doctoral thesis by J.Chlachula. Other work involves an ongoing survey of the magnetic properties of archeological materials. L.Jiang completed an M.Sc. in this area. Sites in Greece (D.Kontopoulou, University of Thessaloniki) and Spain (D.Rey, University of Vigo) are currently being studied. Dr.J.F.Lerbekmo (Professor Emeritus, Department of Earth and Atmospheric Sciences, University of Alberta) continues his independent investigation of the magnetostratigraphy of the Cretaceous and Paleocene in western Canada.
Department of Geology, University of Lethbridge (R.W. Barendregt)
The flourishing of research in the areas of paleoenvironmental reconstruction and global change has underscored the need for reliable geochronological data. Our research has focussed on paleomagnetic properties, as a correlation and dating tool for sediments and rocks of the Quaternary and Neogene. Remanence measurements of deposits containing proxy records of paleoclimates have been carried out in the Canadian Arctic, Canadian Prairies, Canadian Cordillera, East Africa, Colombia, and elsewhere. In addition to providing age constraints, the work has proven valuable as a measure of relative weathering histories, soil formation, and extent of Cordilleran and Laurentide ice in North America. Work is continuing on the magnetic "finger-printing" of auriferous gravels in the Yukon and Alaska, on till magnetostratigraphy of the Canadian prairies and the American midwest to estimate the timing and extent of Laurentide glaciations in North America, on the analysis of sediments from low latitude, high altitude montane environments to estimate extent and timing of glaciations there, and finally, sampling was started for a pole to pole secular variation study, using late Neogene and Quaternary volcanic rocks.
Geological Survey of Canada - Pacific at Victoria (R.J. Enkin, J. Baker, E. Irving)
1) Cordilleran Paleogeography: In order to define better the architecture of Canadian Cordillera and the geodynamic setting of its origin, we have been sampling Cretaceous rocks in the Coast and Intermontane belts to determine the paleogeography of the region (reviewed by Irving et al., 1996). Continued work consistently reveals shallow inclinations reinforcing the conclusion of large coastwise displacements.
2) Diagenetic studies: Magnetic minerals are sensitive to diagenetic environments. We have been looking at the age, geometry and environment of remagnetizations in the southern Canadian Rockies and Western Canadian Basin. Large fluid events are recognized to have flowed ahead of the orogenic zone.
3) Belt-Purcell Basin: Paleomagnetic study shows this mid-Proterozoic basin was deposited during a relatively short duration (~50 m.y.) and suffered differential vertical axis rotations during the Cordilleran orogeny.
4) Quaternary Glacial Magnetostratigraphy: We correlate and date glacial deposits, mostly in the Cordilleran region, and help establish an environmental baseline.
Baragar, W.R.A., Ernst, R.E., Hulbert, L., Peterson, T., "Longitudinal petrochemical variation in the Mackenzie Dyke Swarm, northwestern Canadian Shield.", Journal of Petrology. 1996. 37: 317-359.
Barendregt, R.W., E. Irving, E.A. Christiansen, E.K. Sauer, and B.T. Schreiner, "Stratigraphy and paleomagnetism of Late Pliocene and Pleistocene sediments from southwestern Saskatchewan, Canada: no evidence of ice in the Prairies during the Matuyama Chron.", Canadian Journal of Earth Sciences, 1999, in press.
Barendregt R.W., Vincent J. S., Irving E., Baker J.,"Magnetostratigraphy of Quaternary and late Tertiary sediments on Banks Island, Canadian Arctic Archipelago.", Canadian Journal of Earth Sciences. 1998, 35: 147-161.
Barendregt R.W., Vreeken W.J., Irving E., Baker J.,"Stratigraphy and paleomagnetism of the late Miocene Davis Creek silt, East Block of the Cypress Hills, Saskatchewan.", Canadian Journal of Earth Sciences. 1997, 34: 1325-1332.
Barendregt, R.W, Enkin, R.J., Duk-Rodkin, A., Baker, J., "Paleomagnetic evidence for late Cenozoic glaciations in the Mackenzie Mountains of the Northwest Territories, Canada.", Canadian Journal of Earth Sciences. 1996. 33: 896-903.
Barendregt R.W., Irving E., "Changes in the extent of North American ice sheets during the late Cenozoic.", Canadian Journal of Earth Sciences 1998. 35: 504-509.
Benn, K., Ham, N., Pignotta, G.S. & Bleeker, W., "Emplacement and deformation of granite magmas during transpression: magnetic fabrics of the Sparrow pluton (Archean Slave Province, Canada)". Journal of Structural Geology, 1998. 20: 1247-1259.
Benn, K., Horne, R.J., Kontak, D.J., Pignotta, G.S. & Evans, N.G., "Syn-Acadian emplacement model for the South Mountain Batholith (Meguma Terrane, Nova Scotia): magnetic fabric and structural studies." Geological Society of America Bulletin, 1997. 109: 1279-1293.
Benn, K., Odonne, F. & de Saint-Blanquat, M., "Pluton emplacement during transpression in brittle crust: new views from analogue experiments." Geology, 1998. 26: 1079-1882.
Benn, K., Odonne, F. & de Saint-Blanquat, M., "Pluton emplacement during transpression in brittle crust: new views from analogue experiments. Reply to a Comment by A. Yoshinobu and K. Schmidt." Geology, 1999, in press.
Benn, K., Roest, W., Rochette, P., Evans, N.G. & Pignotta, G.S., "Geophysical and structural signatures of batholith construction: the South Mountain Batholith, Meguma Terrane, Nova Scotia." Geophysical Journal International, 1999, 136: 144-158.
Bijaksana S, Hodych J P, "Comparing remanence anisotropy and susceptibility anisotropy as predictors of paleomagnetic inclination shallowing in turbidites from the Scotian Rise.", Physics and Chemistry of the Earth. 1997, 22 Pages 189-193.
Borradaile G.J., "An 1800-year archeological experiment in remagnetization.", Geophysical Research Letters. 1996, 23: 1585-1588.
Borradaile, G.J. "Experimental stress remagnetization of magnetite.", Tectonophysics. 1996. 261: 229-248.
Borradaile G.J. "Deformation and paleomagnetism.", Surveys in Geophysics. 1997, 18: 405-435.
Borradaile G.J. "Rock magnetic constraints on long-term cliff-slump rates and coastal erosion.", Geotechnique. 1998, 48: 271-279
Borradaile G.J., Brann M. "Remagnetization dating of Roman and Mediaeval masonry.", Journal of Archaeological Science. 1997, 24: 813-824
Borradaile, G.J. Henry, B. "Tectonic applications of magnetic susceptibility and its anisotropy.", Earth-Science Reviews. 1997. 42, 49-93.
Borradaile, G. J., Kehlenbeck, M. M. "Possible cryptic tectono-magnetic fabrics in 'post-tectonic' granitoid plutons of the Canadian Shield.", Earth and Planetary Science Letters. 1996. 137: 119-127.
Borradaile G.J., Lagroix F., King D. "Tilting and transpression of an Archaean anorthosite in northern Ontario.", Tectonophysics. 1998, 293: 239-254
Borradaile G.J., Stupavsky M. "Anisotropy of magnetic susceptibility, measurement schemes.", Geophysical Research Letters. 1995. 22: 1957-1960.
Brassard, P., Morris, W., "Resuspension and redistribution of sediments in Hamilton Harbour.", Journal of Great Lakes Research. 1997. 23, 74-85.
Buchan, K.L., Chandler, F.W."Paleomagnetism of the distal member of the New Glasgow formation, Nova Scotia, Canada: New constraints on magnetic polarity stratigraphy near the base of the Kiaman Superchron.", Journal of Geology 1999 107: in press.
Buchan, K.L., Halls, H.C., Mortensen, J.K.,"Paleomagnetism, U-Pb geochronology, and geochemistry of Marathon dykes, Superior Province, and comparison with the Fort Frances swarm.", Canadian Journal of Earth Sciences. 1996. 33, 1583-1595.
Buchan, K.L., Mortensen, J.K., Card, K.D., Percival, J.A."Paleomagnetism and U-Pb geochronology of diabase dyke swarms of Minto block, Superior Province, Quebec, Canada.", Canadian Journal of Earth Sciences 1998. 35: 1054-1069.
Cheney E.S., Halls H.C., Heaman L.M., "Global mafic magmatism at 2.5 Ga, remnants of an ancient large igneous province?, discussions and reply.", Geology. 1998. 26: 93-96.
Chlachula J., Evans M.E., Rutter N.W., "A magnetic investigation of a late Quaternary loess/palaeosol record in Siberia.", Geophysical Journal International. 1998, 132: 128-132.
Chlachula J., Rutter N.W., Evans M.E., "A late Quaternary loess - paleosol record at Kurtak, southern Siberia.", Canadian Journal of Earth Sciences. 1997, 34: 679-686
Cioppa, M. T., Karlstrom, E. T., Irving, E., Barendregt, R. W., "Paleomagnetism of tills and associated paleosols in southwestern Alberta and northern Montana: evidence for late Pliocene - early Pleistocene glaciations.", Canadian Journal of Earth Sciences. 1995. 32: 555-564.
Costanzo Alvarez V., Dunlop D.J., "A regional paleomagnetic study of lithotectonic domains in the Central Gneiss Belt, Grenville Province, Ontario.", Earth and Planetary Science Letters. 1998, 157: 89-103.
Dang, M.Z., D.G.Rancourt, G.Lamarche and M.E.Evans "Mineralogical analysis of a loess/paleosol couplet from the Chinese Loess Plateau, Can.J.Soil Sci., 1998.
Davis, W. J., Machado, N., Gariepy, C., Sawyer, E. W., Benn, K., "U-Pb geochronology of the Opatica tonalite-gneiss belt and its relationship to the Abitibi greenstone belt, Superior Province, Quebec.", Canadian Journal of Earth Sciences. 1995. 32, 113-127.
Duk-Rodkin A., Barendregt R.W., Tarnocai C., Phillips F.M., "Late Tertiary to late Quaternary record in the Mackenzie Mountains, Northwest Territories, Canada, stratigraphy, Paleosols, paleomagnetism, and chlorine-36.", Canadian Journal of Earth Sciences.1996. 33: 875-895.
Dunlop, D.J., Magnetism in rocks, Journal of Geophysical Research 100, 2161-2174, 1995.
Dunlop, D.J., Thermoremanent magnetization in non-uniformly magnetized grains, Journal of Geophysical Research 103, 30561-30574, 1998.
Dunlop D.J., Argyle K.S., "Thermoremanence, anhysteretic remanence and susceptibility of submicron magnetites: nonlinear field dependence and variation with grain size.", Journal of Geophysical Research. 1997, 102: 20199-20210.
Dunlop, D.J., and O.Ozdemir, "Rock Magnetism: Fundamentals and Frontiers", Cambridge University Press, New York and Cambridge, 573 pp., 1997.
Dunlop D.J., Ozdemir O., Schmidt P.W., "Paleomagnetism and paleothermometry of the Sydney Basin 2. Origin of anomalously high unblocking temperatures.", Journal of Geophysical Research. 1997, 102: 27285-27295.
Dunlop D.J., Schmidt P.W., Ozdemir O., Clark D.A.,"Paleomagnetism and paleothermometry of the Sydney Basin, 1, Thermoviscous and chemical overprinting of the Milton Monzonite.", Journal of Geophysical Research, 1997. 102: 27,271-27,283.
Enkin, R.J., Osadetz, K.G., Wheadon, P.M., Baker, J., "Paleomagnetic constraints on the tectonic history of the Foreland Belt, southern Canadian Cordillera: preliminary results.", Canadian Journal of Earth Sciences. 1997. 34: 260-270.
Enkin, R.J., Watson, G.S., "Statistical analysis of palaeomagnetic inclination data.", Geophysical Journal International. 1996. 126, 495-504.
Ernst R.E., Buchan K.L. "Layered mafic intrusions: a model for their feeder systems and relationship with giant dyke swarms and mantle plume centres.", South African Journal of Geology. 1997, 100(4): 319-334
Ernst, R.E., Buchan, K.L., West, T.D., Palmer, H.C.,"Diabase (dolerite) dyke swarms of the world: first edition.", Geological Survey of Canada Open File 3241, 1996. 104 p.
Ernst, R.E., Buchan, K.L., Palmer, H.C."Giant dyke swarms: Characteristics, distribution and geotectonic applications.", In: Physics and chemistry of dykes. ed.s Baer, G., Heimann, A., Balkema, Rotterdam. 1995, p 3-21.
Ernst R.E., Buchan K.L. "Giant radiating dyke swarms, their use in identifying pre-Mesozoic large igneous provinces and mantle plumes.", In: Large igneous provinces, continental, oceanic, and planetary flood volcanism. ed.s Mahoney J.J., Coffin M.F., American Geophysical Union. Geophysical Monograph. 100. 1997., 297-333.
Ernst, R. E., Head, J. W., Parfitt, E., Grosfils, E., Wilson, L. "Giant radiating dyke swarms on Earth and Venus.", Earth Science Reviews. 1995. 39: 1-58.
Evans M.E."Archaeomagnetic results from the Mediterranean region, an overview.", In: Palaeomagnetism and tectonics of the Mediterranean region. ed.s Morris A., Tarling D.H., Geological Society of London Special Publications. 105. 1996. 373-384.
Evans M E "Significance of paleomagnetic investigations of dyke intrusions.", In: Dyke swarms of Peninsular India. ed. Devaraju T.C.,Memoir - Geological Society of India. 33, 1995. 49-64.
Evans, M.E., Ding, Z., Rutter, N.W., "A high-resolution magnetic susceptibility study of a loess/palaeosol couplet at Baoji, China.", Studia Geophysica et Geodaetica. 1996. 40, 225-233.
Evans M.E., Heller F., Bloemendal J., Thouveny N., "Natural magnetic archives of past global change.", Surveys in Geophysics. 1997, 18: 183-196
Evans, M.E., Jiang, L., "Magnetomineralogy of archeomagnetic materials.", Journal of Geomagnetism and Geoelectricity. 1996. 48: 1531-1540.
Evans, M.E., R.E.Jones, S.Papamarinopoulos, D.Walton, J.Perreault and Ch.Spais, "New Archaeomagnetic Results from Greece", Pact 45, 1997, IV.8: 313-320.
Evans, M.E., D.Kontopoulou, "Archaeomagnetism in Macedonia, Greece: A progress report", Phys.Chem.Earth, 1998. 23: 1027-1028.
Evans, M.E., M.Mareschal, "Archaeomagnetisme au Maroc: Quelques nouveaux resultats", Bull. d'Archeologie Marocaine, XVIII, 1998:175-180.
Evans M.E., Wayman M.L., "Electron microscopy of small magnetic particles in geonomy.", Physics of the Earth and Planetary Interiors. 1997. 103: 343-348.
Forster, T., Heller, F., Evans, M.E., Havlicek, P., "Loess in the Czech Republic: magnetic properties and paleoclimate.", Studia Geophysica et Geodaetica. 1996. 40, 243-261.
Fukuma, K., Dunlop, D.J., "Monte Carlo simulation of two-dimensional domain structures in magnetite.", Journal of Geophysical Research. 1997. 102: 5135-5143.
Fyles J.G., McNeil D.H., Matthews J.V. Jr, Barendregt R.W., Marincovich L. Jr, Brouwers E., Bednarski J., Brigham Grette J., Ovenden L.E., Miller K.G., Baker J., Irving E., "Geology of Hvitland beds (late Pliocene), White Point Lowland, Ellesmere Island, Northwest Territories.", Bulletin Geological Survey of Canada. 1998, 512: 35 p.
Gala M.G., Symons D.T.A., Palmer H.C., "Geotectonics of the Hanson Lake block, Trans-Hudson Orogen, central Canada: a preliminary paleomagnetic report.", Precambrian Research. 1998, 90: 85-101.
Guowei Zhang, Hynes, A., Irving, E., "Block rotations along the strike-slip Finlay-Ingenika Fault, north- central British Columbia: implications for paleomagnetic and tectonic studies.", Tectonics. 1996. 15: 272 287.
Halls H.C., Grieve R.A.F., Robertson P.B., Sharpton Virgil L., Dressler Burkhard O., "New constraints on the Slate Islands impact structure, Ontario, Canada, discussions and reply.", Geology. 1997. 25: 666-669.
Halls H.C., Baoxing Zhang, "Uplift structure of the southern Kapuskasing Zone from 2.45 Ga dike swarm displacement.", Geology. 1998, 26: 67-70
Halls H.C., Zhang Baoxing, "Tectonic implications of clouded feldspar in Proterozoic mafic dyke swarms.", In: Dyke swarms of Peninsular India. ed. Devaraju T.C., Memoir - Geological Society of India. 33: 65-80. 1995.
Han J., Fyfe W.S., Longstaffe F.J., Palmer H.C., Yan F.H., Mai X.S., "Pliocene-pleistocene climatic change recorded in fluviolacustrine sediments in central China.", Palaeogeography Palaeoclimatology Palaeoecology. 1997, 135: 27-39
Harris M.J., Symons D.T.A., Blackburn W.H., Hart C.J.R., "Paleomagnetic and geobarometric study of the mid-Cretaceous Whitehorse Pluton, Yukon Territory.", Canadian Journal of Earth Sciences. 1997, 34: 1379-1391.
Heller, F., Evans, M. E., "Loess magnetism.", Reviews of Geophysics. 1995. 33: 211-240.
Heller, F. and M.E.Evans, "Magnetoklimatologie: Mineralmagnetismus und Eiszeiten", Naturwissenschaften, 83, 97-102, 1996.
Heller, F., T.Forster, M.E.Evans, J.Bloemendal and N.Thouveny, "Gesteinmagnetische Archive globaler Umweltänderungen", GeoArcheoRhein, 2, 151-162, 1998.
Helmens K.F., Barendregt R.W., Enkin R.J., Baker J., Andriessen P.A.M., "Magnetic polarity and fission-track chronology of a late Pliocene-Pleistocene paleoclimatic proxy record in the tropical Andes.", Quaternary Research. 1997, 48: 15-28
Hodych, J.P. Inferring domain state from magnetic hysteresis in high coercivity dolerites bearing magnetite with ilmenite lamellae. Earth and Planetary Science Letters, 1996. 142:523-533.
Hodych, J.P., "Inferring domain state from magnetic hysteresis in high coercivity dolerites bearing magnetite with ilmenite lamellae.", Earth and Planetary Science Letters. 1996. 142, 523-533.
Hodych, J.P., Bijaksana, S. and Pätzold, R., "Using magnetic anisotropy to correct for paleomagnetic inclination shallowing in some magnetite-bearing deep-sea turbidites and limestones." Tectonophysics. 1999. In press.
Hodych J.P., Buchan K.L. "Palaeomagnetism of the ca. 440 Ma Cape St Mary's sills of the Avalon Peninsula of Newfoundland, implications for Iapetus Ocean closure.", Geophysical Journal International. 1998. 135, 1: 155-164.
Hodych, J.P. and Buchan, K.L. 1998. Palaeomagnetism of the ca. 440 Ma Cape St. Mary's sills of the Avalon Peninsula of Newfoundland: implications for Iapetus Ocean closure. Geophysical Journal International, 135, p. 155-164.
Hodych J.P., Mackay R.I., English G.M., "Low-temperature demagnetization of saturation remanence in magnetite-bearing dolerites of high coercivity.", Geophysical Journal International. 1998, 132: 401-411
Irving, E., Baker, J., Wright, N., Yorath, C. J., Enkin, R. J., York, D., "Magnetism and age of the Porteau Pluton, southern Coast Belt, British Columbia: evidence for tilt and translation.", Canadian Journal of Earth Sciences. 1995. 32:380-392.
Irving, E., Thorkelson, D. J., Wheadon, P. M., Enkin, R. J., "Paleomagnetism of the Spences Bridge Group and northward displacement of the Intermontane Belt, British Columbia: a second look.", Journal of Geophysical Research. 1995. 100:6057-6071.
Irving, E., Wynne, P.J., Thorkelson, D.J., Schiarizza, P., "Large (1000 to 4000 km) northward movements of tectonic domains in the northern Cordillera, 83 to 45 Ma.", Journal of Geophysical Research. 1996. 101:17901-17916.
Jackson, L.E. Jr, Barendregt, R.W., Baker, J., Irving, E., "Early Pleistocene volcanism and glaciation in central Yukon: a new chronology from field studies and paleomagnetism.", Canadian Journal of Earth Sciences. 1996. 33:904-916.
Johnston, S.T., Wynne, P.J., Francis, D., Hart, C.J.R., Enkin, R.J., Engebretson, D.C., "Yellowstone in Yukon: the late Cretaceous Carmacks Group.", Geology. 1996. 24: 997-1000.
Koehler G., Kyser T.K., Enkin R.J., Irving E., "Paleomagnetic and isotopic evidence for the diagenesis and alteration of evaporites in the Paleozoic Elk Point Basin, Saskatchewan, Canada.", Canadian Journal of Earth Sciences 1997. 34: 1619-1629.
Koji Fukuma, Dunlop D.J., "Grain-size dependence of two-dimensional microgmagnetic structures for pseudo-single-domain magnetite (0.2-2.5 um).", Geophysical Journal International. 1998, 134: 843-848
Larson M.S., Stone W.E., Morris W.A., Crocket J.H., "Magnetic signature of magnetite-enriched rocks hosting platinum-group element mineralization within the Archean Boston Creek Flow, Ontario.", Geophysics. 1998, 63: 440-445
Lauriol B., Ford D.C., Cinq Mars J., Morris W.A., "The chronology of speleothem deposition in northern Yukon and its relationships to permafrost.", Canadian Journal of Earth Sciences. 1997, 34: 902-911
Lewchuk, M. T., Symons, D. T. A., "Age and duration of Mississippi Valley type ore-mineralizing events.", Geology. 1995. 23: 233-236.
Lewchuk M.T., Symons D.T.A., Al Aasm I.S., Gillen K.P., "Dolomitization of Mississippian carbonates in the Shell Waterton gas field, southwestern Alberta: insights from paleomagnetism, petrology and geochemistry.", Bulletin of Canadian Petroleum Geology. 1998, 46: 387-410
Lewchuk M.T., Symons D.T.A., "Paleomagnetism of Paleozoic carbonates in the Illinois-Kentucky-Tennessee area, the recording of fluid flow events.", In: Carbonate-hosted lead-zinc deposits. ed. Sangster D.F., Special Publication - Society of Economic Geologists. 4: 555-566. 1997.
Lewchuk M.T., Symons D.T.A., "Paleomagnetism and mississippi valley-type ore genesis in the Ordovician Knox Supergroup of central Tennessee.", In: Carbonate-hosted lead-zinc deposits. ed. Sangster D.F., Special Publication - Society of Economic Geologists. 4: 567-576. 1997.
Lian, O.B., R.W. Barendregt, R.J. Enkin, "Lithostratigraphy and paleomagnetism of pre-Fraser glacial deposits in southcentral British Columbia." Canadian Journal of Earth Sciences, 1999, in press.
MacDonald W.D., Palmer H.C., Hayatsu A., "Structural rotation and volcanic source implications of magnetic data from Eocene volcanic rocks, SW Idaho.", Earth and Planetary Science Letters. 1998, 156: 225-237
Mahaney W.C., Barendregt R.W., Vortisch W., "Relative ages of loess and till in two Quaternary palaeosols in Gorges Valley, Mount Kenya, East Africa.", Journal of Quaternary Science. 1997, 12: 61-72
Manning S, Morris W, "High resolution magnetic anomaly maps from ERLIS compilation, an example from Kirkland Lake.", CIM Bulletin (1974). 90, 1012, 89-93. 1997.
Manson M.L., Halls H.C., "Proterozoic reactivation of the southern Superior Province and its role in the evolution of the Midcontinent Rift.", Canadian Journal of Earth Sciences 1997. 34: 562-575.
Mayer T, Morris W A, Versteeg K J, "Feasibility of using magnetic properties for assessment of particle-associated contaminant transport.", Water Quality Research Journal of Canada. 1996. 31: 741-752.
McCausland P J A, Hodych J P, "Paleomagnetism of the 550 Ma Skinner Cove volcanics of western Newfoundland and the opening of the Iapetus Ocean.", Earth and Planetary Science Letters. 1998, 163:15-29.
MacDonald, W.D., Palmer, H.C., and Hayatsu,A. Structural rotation and volcanic source implications of magnetic data from Eocene volcanic rocks, SW Idaho. 1998. Earth Planet. Sci. Lett. 56:225-237.
Morris, W. A., Versteeg, J. K., Bryant, D. W., Legzdins, E. A., McCarry, B. E., Marvin, C. H., "Preliminary comparisons between mutagenicity and magnetic susceptibility of respirable airborne particulate.", Atmospheric-Environment. 1995. 29: 441-3450.
Ozdemir O. and D.J. Dunlop, "Low-temperature properties of a single crystal of magnetite oriented along principal magnetic axes", Earth & Planetary Science Letters 1999. 165: 229-239.
Ozdemir, O., Dunlop, D. J., "Thermoremanence and Neel temperature of goethite.", Geophysical Research Letters. 1996. 23:921-924.
Ozdemir O., Dunlop D.J., "Single domain like behavior in a 3-mm natural single crystal of magnetite.", Journal of Geophysical Research B: Solid Earth. 1998, 103: 2549-2562
Ozdemir O., Dunlop D.J., "Effect of crystal defects and internal stress on the domain structure and magnetic properties of magnetite.", Journal of Geophysical Research. 1997, 102: 20211-20224
Ozdemir, O., Song Xu,, Dunlop, D. J., "Closure domains in magnetite.", Journal of Geophysical Research. 1995. 100:2193-2209.
Palmer, H.C. and MacDonald, W.D., "Anisotropy of Magnetic Susceptibility in Relation to Source Vents of Ignimbrites: Empirical Observations". Tectonophysics 1999(in press).
Palmer, H.C., MacDonald, W.D., Gromme, C.S., Ellwood, B.B., "Magnetic properties and emplacement of the Bishop tuff, California.", Bulletin of Volcanology. 1996. 58: 101-116.
Park, J.K. "Paleomagnetism of the late Neoproterozoic Blueflower and Risky formations of the northern Cordillera, Canada.", Canadian Journal of Earth Sciences 1995. 32: 718-729.
Park, J.K., Buchan, K.L., Gandhi, S.S. "Paleomagnetism of 779 Ma Hottah gabbro sheets of the Wopmay orogen, Northwest Territories.", Geological Survey of Canada, Current Research 1995-C, 195-200.
Park, J.K., Gower, C.F. "Paleomagnetism of pre Grenvillian mafic rocks from the northeast Grenville Province, Labrador: implications for the Grenville Track.", Canadian Journal of Earth Sciences. 1996. 33:746-756.
Park, J.K., Rainbird, R.H."Magnetic overprinting of the Neoproterozoic Shaler Supergroup, Amudsen Basin, Northwest Territories, Canada during the Franklin magmatic episode.", Geological Survey of Canada, Current Research 1995 E, p. 113-123.
Park, J.K."Paleomagnetic evidence for low-latitude glaciation during deposition of the Neoproterozoic Rapitan Group, Mackenzie Mountains, N.W.T., Canada.", Canadian Journal of Earth Sciences 1997. 34: 34-49.
Park, J.K."Paleomagnetism of the Yukon and Northwest Territories.", Geological Survey of Canada Open File 3672, 19 p., 1998.
Park J.K., Buchan K.L., Harlan S.S. "A proposed giant radiating dyke swarm fragmented by the separation of Laurentia and Australia based on paleomagnetism of ca. 780 Ma mafic intrusions in western North America.", Earth and Planetary Science Letters. 1995. 132:129-139.
Pehrsson, S.J., Buchan, K.L."Borden dykes of Baffin Island, Northwest Territories: a Franklin U-Pb baddeleyite age and a paleomagnetic reinterpretation.", Canadian Journal of Earth Sciences 36: in press 1999.
Pignotta, G.S. & Benn, K., "Magnetic fabrics of the Barrington Passage pluton, Meguma Terrane, Nova Scotia: a two-stage fabric history of syntectonic emplacement." Tectonophysics , 1999. in press.
Pippert, R.G., Brown, G.R., Morris, W.A., "Palaeomagnetic chronostratigraphy of Holocene sediments, Niagara Basin, Lake Ontario, Canada.", Journal of Quaternary Science. 1996. 11, 217-231.
Poulton D.J., Morris W.A., Coakley J.P., "Zonation of contaminated bottom sediments in Hamilton Harbour as defined by statistical classification techniques.", Water Quality Research Journal of Canada. 1996. 31 :505-528.
Song Xu, Dunlop, D.J., "Micromagnetic modeling of Bloch walls with Neel caps in magnetite.", Geophysical Research Letters. 1996. 23: 2819-2822.
Spooner, I. S., Osborn, G. D., Barendregt, R. W., Irving, E., "A record of Early Pleistocene glaciation on the Mount Edziza Plateau, northwestern British Columbia.", Canadian Journal of Earth Sciences. 1995. 32: 2046-2056.
Spooner I.S, Osborn G. D, Barendregt R, Irving E, "A middle Pleistocene (Isotope Stage 10) glacial sequence in the Stikine River valley, British Columbia.", Canadian Journal of Earth Sciences .1996. 33:1428-1438.
Symons D.T.A., Sangster D.F., Leach D.L., "Paleomagnetic dating of mississippi valley-type Pb-Zn-Ba deposits.", In: Carbonate-hosted lead-zinc deposits. ed. Sangster D.F., Special Publication - Society of Economic Geologists. 4: 515-526. 1997.
Symons D.T.A., Lewchuk M.T., Simandl G.J., Sangster D.F., "Paleomagnetism of the Mount Brussilof magnesite deposit and its Cambrian host rocks, southeastern British Columbia (NTS 82 J/ 11, 12, 13).", British Columbia Geological Division Geological Fieldwork. 307-315. 1997.
Symons D.T.A., Sangster D.F., Leach D.L., " A Tertiary age from paleomagnetism for mississippi valley-type zinc-lead mineralization in Upper Silesia, Poland.", Economic Geology and the Bulletin of the Society of Economic Geologists. 1995. 90,: 782-794.
Symons, D. T. A., Lewchuk, M. T., Boyle, D. R., "Pliocene-Pleistocene genesis for the Murray Brook and Heath Steele Au-Ag gossan ore deposits, New Brunswick, from paleomagnetism.", Canadian Journal of Earth Sciences. 1996. 33: 1-11.
Symons D.T.A., Lewchuck M.T., Sangster D.F, "Laramide orogenic fluid flow into the western Canada sedimentary basin: evidence from paleomagnetic dating of the Kicking Horse Mississippi Valley-type ore deposit.", Economic Geology. 1998, 93: 68-83
Symons D.T.A., Sangster D.F., Leach D.L., "Paleomagnetism of the mississippi valley-type Zn-Pb deposits of the Silesian-Cracow area, Poland.", In: Carbonate-hosted zinc-lead deposits in the Silesian-Cracow area, Poland. ed.s Gorecka E. , Leach D.L., Prace Panstwowego Instytutu Geologicznego (1988). 154, 157-162. 1996.
Versteeg, J. K., Morris, W. A., Rukavina, N. A., "The utility of magnetic properties as a proxy for mapping contamination in Hamilton Harbour sediment.", Journal of Great Lakes Research. 1995. 21: 71-83.
Versteeg, J.K., Morris, W.A., Rukavina, N.A., "Mapping contaminated sediment in Hamilton Harbour, Ontario.", Geoscience Canada. 1995. 22: 145-151.
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Wang Y, Evans M E, "Paleomagnetism of Canadian Arctic permafrost, Quaternary magnetostratigraphy of the Mackenzie Delta.", Canadian Journal of Earth Sciences 1997. 34: 135-139.
Werner, T., Borradaile, G. J. "Paleoremanence dispersal across a transpressed Archean terrain: deflection by anisotropy or by late compression?", Journal of Geophysical Research. 1996. 101: 5531-5545.
Werner T., Borradaile G.J. "Homogeneous magnetic susceptibilities of tektites: implications for extreme homogenization of source material.", Physics of the Earth and Planetary Interiors. 1998 108: 235-243
Williams, W. and D.J. Dunlop "Simulation of magnetic hysteresis in pseudo-single-domain grains of magnetite" Journal of Geophysical Research 1995. 100, 3859-3871.
Wright T.M., Williams W., Dunlop D.J., "An improved algorithm for micromagnetics.", Journal of Geophysical Research. 1997, 102: 12085-12094
Wynne, P. J., Irving, E., Maxson, J. A., Kleinspehn, K. L., "Paleomagnetism of the Upper Cretaceous strata of Mount Tatlow: evidence for 3000 km of northward displacement of the eastern Coast Belt, British Columbia.", Journal of Geophysical Research. 1995. 100: 6073-6091.
Xu, S., and D.J. Dunlop, Toward a better understanding of the Lowrie-Fuller test, Journal of Geophysical Research 1995. 100, 22533-22542.
Compiled by Dr. Alan Manson, April 1999
ISAS, University of Saskatchewen,
(Member of Solar Terrestrial Relations Advisory Committee (STRAC),
Canadian Space Agency; CNC for SCOSTEP).
The impact of SCOSTEP's STEP (1990-1998) and of the new S-RAMP, PSMOS, and EPIC programs (1998-2002) have been and will be strong and empowering for the Atmospheric Sciences community. Several Canadians are involved with the administration of these eg. Gordon Shepherd and Alan Manson. The CNSR (1991-95) Network allowed for the development of several ground-based instruments which have made global/international links more effective. These systems have also played a role in CEDAR programs, which are very complementary with the SCOSTEP activities. Linkages with the Canadian Space Agency's (CSA) satellite systems eg WINDII, Odin-OSIRIS, MOPITT, ACE ( discussed below) and the CSA's Space Science Program, are providing powerful synergistic opportunities, which are now complemented by the Canadian GCM Model (CMAM) and growing related linkages with the Atmospheric Environment Service (AES).
Firstly, an update on the majority of the GROUND-BASED systems which are presently in use is given:
1.) Dynamics/MF radars (MFR), University of Saskatchewan, (Drs. Alan Manson, Chris Meek). One of the two CNSR (1990-95) radars has been used to improve the Tromso MFR ( a collaboration with the Universities of Tromso and Nagoya): this is colocated with EISCAT at Ramfjordmoen, and is being used for studies of turbulence, gravity, tidal and planetary waves, and for ALOMAR collaborations. The other CNSR MFR is being installed at Platteville, near Boulder, Colorado, along with other CEDAR systems, as a joint venture. The Saskatchewan MFRs and a Saskatoon All-Sky-Imager ( Sodium ), along with other systems at/near London (43N), Toronto ( 45N) and Resolute Bay (75N) are allowing enhanced North American (NA) and global assessment of wind and wave processes, and of coupled aeronomy. These contribute to the Mesosphere/ Lower Thermosphere (MLT) studies for CEDAR and PSMOS campaigns. Recent Saskatoon studies have included assessments of Gravity Wave spectra and variances, and the influences of tides and planetary waves upon GW fluxes. Doppler shifting has been shown to be have a seasonally varying influence; and the effects of planetary waves and tides to be very intermittent due to variability of GW sources.
The use of SuperDARN, a global radar network for magnetospheric convection and 'Space Weather' studies, is also proving very useful for the measurement of MLT winds, using meteor detection. The monthly tidal oscillations at 6 high latitude locations show excellent agreement with MFRs ( Dr George Sofko, Canadian P.I.), and will play a significant PSMOS role.
2.) Radars, University of Western Ontario (UWO) ( Drs Wayne Hocking, John MacDougall). VHF radars (ST (stratosphere-troposphere) turbulence and Meteor scatter) are operated at London and Resolute Bay ( Hocking ). The CLOVAR radar has continue to function well and reliably in both modes and refinements have continued eg. antenna and algorithm improvements now allow typically 800 meteors per day to be satisfactorily detected. This has improved the comparisons with the MF radar, and also has produced 'absolute' temperatures from the meteor decay-times. The Resolute Bay radar is 'on-line' in both MST and meteor modes. A mobile meteor radar (1500-3000 per day) and commercial versions now exist, and these have run at Saskatoon, London, Albuquerque, with installations in Australia and Brazil.
The London MFR ( Hocking, MacDougall ) has operated since 1993, and extensive collaborations with the Saskatoon MFR are underway. These include tidal, planetary and gravity studies, including their mutual interactions. The CADI ( MacDougall ) digital ionosonde has been modified ( signal processing ) to allow detection of meteors and MF scatter. Meteor height distributions at various frequencies will be available.
3.) Hydroxyl airglow studies at UWO (Bob Lowe, Dave Turnbull, Kathy Gilbert, Vladimir Perminov, Stella Melo). Regular observations with UWOMI (a near infrared Fourier transform spectrometer) continue to be made on about 4 nights per month to obtain rotational temperatures for use in gravity wave and long term trend studies. Satisfactory comparisons of these temperatures with a Na temperature lidar, and assessments of the temperature trend over the period 1966 to 1998, have been completed. The scanning radiometer (UWOSCR) which had been located at the Observatoire de Haute Provence in France for WINDII correlative studies was moved to Australia in 1998 and thence successfully installed at the Davis Antarctic station (69 S) where it will be operated for the next few years in collaboration with the Australian Antarctic Division. Other UWOSCR's are located at the ALOMAR Observatory in Norway (69 N) and the Delaware Observatory (43 N) near London Ontario. Improved software has been developed for the measurement of gravity wave parameters from these instruments. During the summers of 1997 and 1998, correlative measurements were made with a UWOSCR and the 50 MHz Valensole radar (Prof. Jean Delloue) over the Grenoble region in France in an attempt to seek correlation between gravity wave activity and spradic-E. Data from WINDII hydroxyl observations continue to be used, both alone and in combination with ground-based measurements, in studies of seasonal, solar-cycle and tidal effects in the mesopause region. As well, the phenomenon of double-peaked airglow layers which occur nearly 10% of the time is under investigation.
4.) Purple Crow Lidar, UWO (Dr. Bob Sica and colleagues). The Purple Crow Lidar (PCL) is a monostatic system which simultaneously measures temperature using vibration Raman-scattering (from molecular nitrogen), Rayleigh-scatter and sodium resonance fluorescence scatter from 10 - 105 km altitude, as well as composition of water vapour from the surface to the middle stratosphere. The PCL is particularly well suited for high temporal-spatial studies of gravity waves, due in part to the use of 2.65 m diameter liquid mirror and a high power transmitter. The evolution of the gravity wave spectrum in time and space has been shown to be highly intermittent; narrow regions of potential convective instability and stability have been identified. Gravity wave energy dissipation and eddy diffusion have been estimated from measurements from the Rayleigh-scatter system. The sodium resonance fluorescence system is now beginning temperature measurements. Measurements of water vapour mixing ratio in the troposphere and stratosphere have also begun. There is particular interest in these measurements as they pertain to studies of stratosphere- troposphere exchange.
5.) CRESTech Lidars, York University. The Lidar Group (Allan Carswell) has continued to work with David Wardle's Group at AES in the operation of the stratospheric observatory at Eureka. They now have seven winters (typically November to March) of excellent lidar data on stratospheric ozone, aerosol, temperature and gravity waves at Eureka. These data are available as part of the archive of the Network for the Detection of Stratospheric Change (NDSC) at http://climon.wwb.noaa.gov/. The observations at Eureka have proven to be particularly useful in view of the dominant effects of the polar vortex on the properties of the stratosphere. During the lidar observations the vortex has moved over Eureka a number of times providing excellent opportunities to study the atmospheric properties both inside and outside of this important polar feature. The CRESTech Lidar Group is continuing its collaboration with MPB Technologies (and UQAM, CCRS and CMC) on a study of Synergetic Observations of Earth Radiation Mission instruments for ESA. The lidar group also continues its collaboration with Optech as part of a joint CSA/NASA study on the development of a spaceborne differential absorption lidar (DIAL) system for global ozone and aerosol measurements.
6.) Optical Measurement Systems, York University (Drs. Gordon Shepherd, Bill Gault, Rudy Wiens and Stephen Brown). A spectral airglow temperature imager (SATI), a multichannel all-sky imager (YASAC), and a wide-angle Michelson interferometer (GWAMDI) are being operated at the AES Egbert facility 60 km north of campus. The station is especially useful for rotational temperature measurements of the OH and O2 nightglow layers, winds in the O(1S) and OH layers, and emission rates of all three layers. The group has collaborated internationally so that SATIs have functioned since 1997 in Egbert, Spain, Kazakhstan, and Japan as part of the PSMOS program for the study of mid-latitude gravity waves, tides, etc. on a planetary scale.
The E-Region Wind Interferometer (ERWIN) is a field-widened Michelson interferometer which has been measuring winds near the mesopause from Resolute Bay since 1992. It is operated remotely through a telephone link from Toronto. It determines the wind at three altitudes by measuring the Doppler shifts of the OI 557.7 nm, OH (6,2) and O2 Atm (0,1) nighttime airglow emissions, with a time resolution of 20 minutes and a wind precision of about 3 m/s. When a single emission is observed, the time resolution can be as low as 4 minutes. A comparison of ERWIN's winds with those of the University of Michigan's Fabry-Perot interferometer at Resolute shows excellent agreement.
The MODELLING activity in Canada is dominated by the Middle Atmosphere Model project (Dr. Ted Shepherd, Univ. of Toronto, P.I.) which is continuing its development of a Canadian 3-D troposphere-stratosphere-mesosphere general circulation model. The climatology of the first-generation model (Atmos-Ocean, 1997) represented the first published climatology of a middle atmosphere model that included the entire mesosphere. Another important first is the identification of realistic tidal structures in the upper mesosphere of the model, whose annual variation agrees well with WINDII observations (C. McLandress). A MAM-initiated intercomparison of middle atmosphere models has revealed a rich spectrum of divergent motion in the mesosphere, with a much shallower horizontal wavenumber spectrum than that associated with the balanced motions that dominate the stratosphere (J. Koshyk). This offers interesting prospects for comparison with both space- and ground-based measurements. Recently the upper lid of the model has been raised to 190 km, which allows a clean simulation of large-scale neutral phenomena in the critical upper mesosphere/lower thermosphere region (W. Ward, V. Fomichev). Interactive chemistry is also included; and aerosols and heterogenous chemistry is being tested for inclusion. The Canadian MAM is presently being used in the context of the AES's Middle Atmosphere Initiative, applying the AES's 3-D variational system to perform middle atmosphere data assimilation. After assimilating the UARS ozone, temperature, and wind datasets, an attempt will be made to perform the first-ever assimilation of upper mesospheric data, using WINDII wind data. There is, and will be, considerable collaboration and linkages between MAM and the ground-based systems discussed above, especially with regard to GW fluxes and parameterization schemes.
The ATMOSPHERIC SATELLITE system now in operation is WINDII (Dr. Gordon Shepherd, P.I., York University). WINDII operations have continued over 7.5 years now (Brian Solheim, York), and no degradation in instrument performance has been detected (Bill Gault, York). Upper mesosphere and lower thermosphere tides have been characterized (Charles McLandress, York), and an empirical model developed (Ding Yi Wang, CRESTech). The influence of dynamics on emission rates has been studied, including that of the two-day waves (William Ward, CRESTech) for O(1S), and also for OH (Bob Lowe, UWO). In particular, the tidal influence has been studied (Stella Melo, UWO), and the influence on O(1S) and OH emissions shown to be consistent (Shengpan Zhang, York) and in excellent agreement with the TIME-GCM model (Ray Roble, HAO/NCAR). Mesospheric temperatures from Rayleigh scattering have been determined (Marianna Shepherd, York), and the morphology of polar mesospheric clouds studieds, as well as observations of polar stratospheric clouds and stratospheric airglow (Wayne Evans, Trent University). Thermospheric atomic oxygen densities have been determined (Ian McDade, York) and new measurements of nitric oxide concentration have been made (Christian Kurz, York). The dayside equatorial thermospheric response to magnetic storms has been studied (Rudy Wiens, York). Other topics that have been studied are 1) the springtime transition, 2) stratospheric warmings, 3) solar cycle influence including flares, 4) long-term trends in emission rates. The complete set of WINDII data is now being reprocessed with version V5_11 of the analysis software which includes winds from the O2 emission for the first time, and many other improvements including more accurate error estimates (Yves Rochon, AES).
Considerable efforts continue on the development and integration of new GROUND BASED and REMOTE SENSING ( balloon and satellite) systems for comprehensive studies, which enable high temporal and spatial resolutions. These are collaborative programmes involving the CSA, the AES, and the granting agency NSERC. The Major examples are given below:
1.) Ground-Based UV-Visible Spectroscopy / MANTRA ( Dr Kim Strong, P.I., University of Toronto). A new portable ground-based UV-visible zenith-sky spectrometer has been assembled at the University of Toronto. It is intended to measure the total vertical column abundances of ozone, NO2, BrO, and OClO using the technique of differential optical absorption spectroscopy. The instrument includes a triple-grating spectrometer and a CCD detector, and will later be optically coupled to an 11-inch Cassegrain telescope to make night-time measurements. It was first operated in Vanscoy, Saskatchewan, in August 1998 as part of the MANTRA balloon campaign ( below) where it was successfully used to measure ozone and NO2. It has recently been deployed in Eureka, NWT, where it will be making measurements during March-May, 1999.
The MANTRA (Middle Atmosphere Nitrogen TRend Assessment) Balloon Campaign was successfully launched from Vanscoy, Saskatchewan on August 24, 1998. The balloon carried a payload of scientific instruments, three of which were flown on balloons 15-20 years ago and three of which employed newer technology. In addition, background atmospheric measurements were made through August, using ozonesondes, radiosondes, aerosol sondes, a Brewer spectrophotometer, and two zenith-sky spectrometers. The goal of the MANTRA project is to investigate changes in the concentrations of stratospheric ozone, and of nitrogen and chlorine compounds. The MANTRA Science Team includes Drs. Kim Strong (U of Toronto, PI), Tom McElroy (AES, Environment Canada Lead Scientist), Jim Drummond (U of Toronto), Jack McConnell (York U), Brian Solheim (York U/CRESTech), Frank Murcray (U of Denver), Pierre Fogal (U of Denver), and Dale Sommerfeldt (SIL, Saskatoon). MANTRA is supported by the Canadian Space Agency, AES (Environment Canada), and CRESTech.
2.)OSIRIS (Odin satellite) Report. The work on this program (Drs.Ted Llewellyn P.I. and co-I's Evans, Gattinger, McConnell, McDade, Solheim and Strong) has continued. The Flight Model of the OSIRIS (optical spectrograph infrared imaging system) instrument was delivered to Sweden in May 1998 and is presently awaiting integration on to the spacecraft. Unfortunately the launch has been postponed until some time late in 1999. Over the last 2 years there has been a very significant effort to develop robust algorithms that include the full instrument calibration and characterization knowledge for the uv/visible retrieval of atmospheric constituents. There have also been direct tests of the OSIRIS instrument performance using both NO2 and ozone cells. In the latter case measurements were made using both a quartz halogen lamp and Rayleigh scattered sunlight as the illuminating source. The infrared retrieval algorithm work, including both the true instrument performance and the tomographic capability, is almost complete and is awaiting data from the real Odin satellite to validate its operation. Work is also progressing, in collaboration with the AES, to test the possibility of assimilating the Odin's ozone data using the Canadian weather forecasting or MAM models.
During the last year 1998/9 there have also been on-going efforts to include the instrument in other satellite missions.
3.)MOPITT (Dr. Jim Drummond, PI, University of Toronto, Drs. Jack McConnell, Gary Davis et al); Measurements of Pollution In the Troposphere experiment. MOPITT will make measurements of carbon monoxide and methane in the lower atmosphere. These measurements are important to our understanding of pollution and climate effects. The mission is a collaboration of Canada and the US with a science team drawn from both countries and the UK. The instrument was constructed in Canada by a group of Canadian companies led by COMDEV. The flight model is completed and awaiting launch on NASA's "TERRA" satellite as part of the "Earth Observing System". Launch is scheduled for July 1999. An aircraft model (MOPITT-A) is being built to assist with the validation of the flight instrument. This will be flown in the Western US and Canada in Fall 1999 and in Southern Africa in the Fall of 2000. Plans are also being made to fly the instrument on a balloon payload (MOPITT-B) in collaboration with French scientists in mid-2001.
4.) ACE (Dr. Peter Bernath, P.I., University of Waterloo, McConnell, et al.); Atmospheric Chemistry Experiment (The "Canadian Scientific Satellite"). The goal of ACE is to study the chemistry and dynamics of ozone depletion in the stratosphere. A high resolution infrared Fourier transform spectrometer, augmented by a filtered solar imager, will be launched into low earth orbit in late 2001. ACE will measure solar occultation spectra of a suite of about 30 atmospheric molecules as well as aerosols and clouds. Bomem will build the instrument and Bristol Aerospace will make the satellite bus.
CONCLUSION: The activity in Canada is vigorous, collaborative and creative. The programs and key workers mentioned above represent a large community which is engaged fully with national and international programs and networks. The activities of SCOSTEP with PSMOS and SRAMP(STEP), and of CEDAR and SPARC, will strongly enhance the research: Canadians are playing leadership roles in these programs. Collaborations with the Canadian Space Agency (CSA Space Science Program, Barry Wetter, Director General; Dr. David Kendall, Acting Director-Program Development ) and the Atmospheric Environment Service (AES), are strong and effective in integrating and developing the scientific resources within ground-based, satellite and modelling activities.
World Wide Web Home Pages
1. ISAS UofSask. Contains ISAS, SuperDARN, Odin-OSIRIS, MLTCS-STEP/PSMOS
http://www.usask.ca/physics/isas/
2. UWO - Lidar
3. York - WINDII
http://www.stpl.ists.ca/windii/windii.html
4. York - Lidar Group
5. Toronto-MOPITT / MANTRA / Atmospheric Physics
http://www.atmosp.physics.utoronto.ca/MOPITT/home.html
http://www.atmosp.physics.utoronto.ca/
http://www.atmosp.physics.utoronto.ca/MANTRA/home.html
6. MAM
http://www.atmosp.physics.utoronto.ca/MAM/home.html
PART B SPACE PLASMA RESEARCH
Compiled 1997 by Gordon Rostoker, University of Alberta
Updated April 1999 by David Knudsen, University of Calgary, and others
Canadian researchers are active in several diverse areas of space plasma physics research. Major center of activity are found in several universities, notably the University of Calgary, University of Alberta, University of Saskatchewan, and University of Western Ontario. Individual researchers are found in University of Victoria, University of New Brunswick (Fredericton) and Memorial University of Newfoundland. Research activity is also found at Communications Research Center, Geological Survey of Canada(Geomagnetism Division) and in the Canadian Space Agency (SpaceScience Program).
Major Canadian space physics projects include the following:
UV AURORAL IMAGING from Space - University of Calgary. During the period 1995-1999, scientific analysis was conducted on data from the Freja Ultraviolet Imager (UVAI, P.I.: J. S. Murphree), while another UVAI instrument (P.I.: L. Cogger) was launched on the INTERBALL Auroral probe in 1996. Studies conducted with these instruments involve structure, morphology and dynamics of the auroral oval, dynamics of substorm and substorm particle injections, and electrodynamics of plasma within substorm surges. Drs. L. Cogger, J. S. Murphree, and T. Trondsen are members of the science team for theNASA IMAGE FUV Imager to be launched in early 2000. Please see http://www.phys.ucalgary.ca
IN-SITU STUDIES OF LOW-ENERGY Charged Particles - University of Calgary. The Akebono Suprathermal Ion Mass Spectrometer (SMS, P.I. A. W. Yau) continues to operate after 10 years taking data in the terrestrial auroral and polar cap regions. SMS studies have quantified particleand energy fluxes of outflowing ions as a function of ion composition using a RF mass spectrometer design. Studies by the Freja Cold Plasma Analyzer (CPA, P.I.: D. Knudsen) have focused on the fine structure of ion energization and its relation to different types of plasma wave and electron precipitation. The Thermal Plasma Analyzer (TPA, P.I. A. W. Yau) was launched in July 1998 on the Japanese Nozomi spacecraft and is presently en route to the Martian ionosphere to study plasma density, temperature, drifts and composition. A TPA instrument was flown on the ACTIVE sounding rocket from Churchill, Manitoba in April 1998 (P.I.: G. Garbe). Miniaturized versions of a CPA-like instrument using an electro-optical detection scheme are being readied for launch on the GEODESIC sounding rocket in early 2000 (P.I.: D. Knudsen), with the goal of observing rapid changes in 2-D thermal plasma distributions and their correlation with plasma waves. Please see http://www.phys.ucalgary.ca
GROUND BASED AURORAL IMAGING - University of Calgary. Drs. T. Trondsen and L. Cogger study fine structure within auroral arcs using a portable telescopic, image-intensified TV camera, showing dynamic structures at scales down to a few tens of meters. See http://www.phys.ucalgary.ca/~trondsen/pai/ A network of all-sky imaging auroral cameras operating in white light and at filtered wavelengths - "NORSTAR" (P.I.: Dr. Eric Donovan) - is being prepared for deployment in early 2000. See http://www.phys.ucalgary.ca/NORSTAR
Canada's involvement in the ISTP PROGRAM is found in the Global Geospace Science (GGS) program where the ground based CANOPUS array of magnetometers, riometers and photometers (PI: Dr. G. Rostoker, University of Alberta) continues operations which commenced in late 1989. The CANOPUS array will operate until the end of 1999; a proposal for its continued operation is being led by Drs. J. Samson (University of Alberta) and E. Donovan (University of Calgary). Ground based magnetometer coverage across North America is also provided by the Geological Survey of Canada (GSC, Group Leader: Dr. R. Coles) and both CANOPUS and GSC data can be made available in near real time. Data are also acquired from Canadian sites by Japanese researchers, and Dr. R.E. Horita continues collaborative research with colleagues from the University of Tokyo involving data from the Global Aurora Dynamics Campaign and also a data acquisition system for the collection of magnetometer data from the Rocky Point field site near Victoria, B.C. Please see http://www.phys.uvic.ca. Dr. D. McDiarmid and co-workers have been exploring the relationship between geomagnetic pulsation observations made near the magnetospheric equatorial plane and those made with ground-based instruments. The main intent has been to illuminate the reported discrepancy between these observations and to determine how well current magnetospheric waveguide theory can explain these observations. The theory survives and the testing continues.
AURORAL RADARS - University of Saskatchewan, University of Western Ontario, University of New Brunswick. There is a continuing strong program of research involving auroral radars in Canada. The University of Saskatchewan is the headquarters for the Canadian component of the international SuperDARN HF radar program (Canadian PI Dr. G.J. Sofko). The SuperDARN team is building a radar at Prince George, B.C., to be paired with the Alaska radar being built at Kodiak; both radars should be operational by Nov. 1999. Currently the major fields of SD research are large-scale plasma convection and field-aligned currents (G.J. Sofko, A. V. Kustov, C.-S. Huang), large-scale quasi-stationary vortices and small-scale vortices (Sofko, Huang, M. Huber) and travelling convection vortices (Kustov), sources and propagation characterisitcs of gravity waves (C.-S. Huang, G.C. Hussey, D. Andre), and meteor winds (Sofko, Hussey, Andre) in conjunction with MF radar neutral winds and tides(A. H.Manson, C.E. Meek). The use of VHF radars to study plasma wave processes in the lower E-region continues on a campaign basis (Hussey). Please see: http//radar.usask.ca/radar.html.
The compact Canadian Advanced Digital Ionosondes have been operating routinely at Eureka, Resolute Bay, Cambridge Bay and Rabbit Lake for several years (Drs. MacDougall and Jayachandran, UWO). They measure convection as well as recording standard ionograms. These measurements have resulted in some important findings about the polar cap ionosphere including gravity waves, ionospheric blobs, convection responses to IMF, and sporadic E structures. Research using SuperDARN, CADI, ground-based magnetometer and ISTP data to identify solar wind sources of ionospheric cusp convection transients and resulting ionospheric structure (polar patches) is being carried out by Dr. P. Prikryl (Communications Research Centre). Theoretical studies of auroral radar echoes are being carried out by Dr. A. Hamza (University of New Brunswick) and Dr. J.P. St.-Maurice (University of Western Ontario). Dr. Hamza is also continuing his research on ion acoustic waves in the auroral acceleration region.
At the University of Alberta, the emphasis continues to be on COMPUTER MODELLING of the magnetosphere-ionosphere interaction (Drs. J.C. Samson and R. Sydora.) The group has recently been augmented by the arrival of Visiting Assistant Professor Dr. F. Fenrich who has had extensive involvement with SuperDARN radar data analysis. As well, Dr. R. Rankin has recently been appointed to the Faculty and will continue his work with Dr. Samson and Research Associate Dr. I. Voronkov on the mechanism thought to be responsible for substorm expansive phase onset. The substorm problem is also under investigation by Dr. G. Rostoker using CANOPUS data and data from the ISTP constellation of satellites. He and CSA Research Fellow Dr. William Liu have an active interest in possible mechanisms for the acceleration of electrons to near relativistic energies in regions outside the normal position of the outer radiation belt. There is also an active interest at University of Alberta in the physics of auroral arcs, which parallels studies at the University of Calgary led by Dr. L.L. Cogger. As well, the origin of auroral arcs in the polar cap region continues to be addressed by Dr. D.J. McEwen (University of Saskatchewan).
Dr. Martin Conners of Athabasca University works on INVERSION OF MAGNETIC DATA and instrument development, and has interest in Ps 6 phenomenology. He runs a magnetometer in collaboration with UCLA (Russell) gathering 1-second 3-component magnetic data.
IN-SITU RADIO SCIENCE - Communications Research Centre, University of Calgary, York University, University of Western Ontario, University of Toronto, University of Victoria, Magnametrics.
Direct experimentation on space plasmas using wave techniques is carried out on various topics, including ionospheric density structures and dynamics, the generation, propagation and detection of electromagnetic and electrostatic waves and wave-spacecraft interactions. The nonlinear consequences of high-amplitude RF fields are studied. Theoretical and experimental work on dc and ac probes and on antennas in magnetoplasmas is carried out. Common interests in spontaneous instabilities producing radio emissions link this part of the community with the charged-particle group mentioned above. Likewise, future experiments coordinated with ground radio facilities are sought.
Data from the very successful launch in November 1995 of the rocket OEDIPUS-C are under analysis. This featured a conducting tether linking two separated sections of the rocket payload, instrumented for wave and particle measurements. This experiment was led by Dr. H.G. James (Communications Research Centre) and involves scientists in Canada and abroad. Please see http://www.dan.sp-agency.ca/www_oedipus/oedc_over.html
Canadians are not extensively involved in studies of the SUN or the INTERPLANETARY MEDIUM , although the continuing measurements of the F10.7 radio noise from the sun by Dr. K. Tapping (DRAO, Penticton) has provided an extremely important long term proxy for solar activity which is used by many researchers and prediction services around the world. Dr.D.Summers (Memorial University of Newfoundland)has recently been working on (1) The relativistic theory of wave-particle resonant diffusion with application to electron acceleration in the earth's magnetosphere (2) Instability of electromagnetic R-mode waves in relativistic plasmas with application to planetary magnetospheres (3) Formation of power-law energy spectra in space plasmas by stochastic acceleration due to whistler-mode waves (4) Nonlinear dynamics of corotating plasma in Jupiter's magnetosphere.
CONCLUSION to Parts A and B:
The Canadian STP community is a large and yet coherent group of
scientists, engineers, and graduate students. There is good and effective
communication between the "Atmospheric Environment" and "Space Environment"
areas. This is encouraged by the overlap between the areas, which is demanded
by the complexity of STP processes, and the powerful coupling between atmospheric
and plasma regions. The CSA provides mechanisms, especially through STRAC
(Solar Terrestrial Relations Advisory Committee to the CSA )) for the STP
community to operate in the most effective fashion.