Details: Approximately 30 375 line kilometres of high-resolution aeromagnetic data were acquired in the Atlin map area (NTS 104N), northwestern British Columbia, between September 2000 and March 2001. The survey, flown by SIAL Geosciences Inc. under contract to the Geological Survey of Canada, was funded by the federal government's Targeted Geoscience Initiative. Much of the surveyed area is underlain by oceanic sedimentary, volcanic, and volcaniclastic rocks interleaved with structural panels of ultramafic and other ophiolitic rocks that make up the Cache Creek Terrane. Significant contrasts in magnetic properties among many of these rock types result in a data set that is rich in magnetic anomalies and trends and, as such, a valuable aid to bedrock mapping and mineral exploration currently underway in the region.
Atlin Geophysics Map
Lowe, C. and Anderson, R.G. (2002): Preliminary Interpretations of new aeromagnetic data for the Atlin map area, British Columbia, Geological Survey of Canada, Current Research 2002-A17; 11 pages. View metadata from GEOSCAN. Download report in PDF from GEOSCAN.
Dumont, R., Coyle, M., Potvin, J. (2001): Aeromagnetic total field maps for 104N are covered by sixteen 1:50,000-scale sheets, GSC Open Files 4091 to 4106.
Atlin Targeted Geoscience Initiative 2000-2003: Overview of the Atlin Intergrated Geoscience Project, Northwestern British Columbia; Lowe, C.; Mihalynuk, M.G. Geological Survey of Canada, Current Research No. 2002-A6, 2002; 7 pages. View metadata from GEOSCAN. Download report in PDF from GEOSCAN.
Mihalynuk, M.G.; Lowe, C. (2002): Atlin TGI, Part I: An introduction to the Atlin Targeted Geoscience Initiative; in Geological Fieldwork 2001; British Columbia Ministry of Energy and Mines, Paper 2002-1; pages 1-4.
Mihalynuk, M.G.; Johnston, S.T.; Lowe, C.; Cordey, F.; English, J.M.; Devine, F.A.M.; Larson, K.; Merran, Y. (2002): Atlin TGI Part II: Preliminary results from the Atlin Targeted Geoscience Initiative, Nakina area, northwest British Columbia; in Geological Fieldwork 2001; British Columbia Ministry of Energy and Mines, Paper 2002-1, 2002; pages 5-18
How the Magnetic and Radiometric Maps Can be Used:
Multiparameter (gamma-ray, magnetic) geophysical surveys are useful in mineral exploration and bedrock mapping studies. In the Atlin area, magnetic-anomaly data accurately delineate many mapped rock units and structures. The potassium, potassium/thorium, magnetic total field and magnetic vertical gradient maps can be used to help identify potassic alteration and magnetite enrichment/depletion zones associated with copper-gold mineralization, and also help in mapping lithologies and structures. For additional information on the GSC Radiation Geophysics NATGAM program and interpretation of radiometric maps, go to http://www.nrcan.gc.ca/earth-sciences/products-services/geoscience-data-repository/11844 .
Original Source Data:
Dumont, R.; Coyle, M.; Potvin, J. (2001): Aeromagnetic total field maps for 104N are covered by sixteen 1:50,000-scale sheets, GSC Open Files 4091 to 4106.