Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by CHENG, L.Z. Articles by FOUNTAIN, D.K. Search for Related Content GeoRef GeoRef Citation

Geophysical Case Study of the Iso and New Insco Deposits, Québec, Canada, Part I: Data Comparison and Analysis

¹ Université du Québec en Abitibi-Témiscamingue, Rouyn-Noranda, Québec J9X 5E4.
² Fugro Airborne Surveys, 2060 Walkley Road, Ottawa, Ontario K1G 3P5.
³ Noranda Inc., Division de l’Exploration, 3296 avenue Francis Hughes, Laval, Québec H7L 5A7.
⁴ Geological Survey of Canada, Natural Resources Canada, 615 Booth Street, Ottawa, Ontario K1A 0E9.
⁵ École Polytechnique de Montréal, Départment des Génies Civil, Géologique et des Mines, Montréal, Québec H3C 3A7.
⁶ Fugro Airborne Surveys, 5610 Chemin Bois-Franc, St. Laurent, Montréal, Québec H4S 1A9.

A test survey using the MEGATEM^II airborne electromagnetic system was flown over the Iso and New Insco massive sulfide orebodies in the Rouyn-Noranda mining camp, Canada. The results were compared with data from historical systems (INPUT, DIGHEM) used to discover the deposits. The historical data show that the two deposits have comparable conductances. However, the modern MEGATEM^II system reveals that the New Insco deposit has a much slower decay than the Iso deposit, and it is, therefore, interpreted to be more conductive. The MEGATEM^II anomaly maps provide estimates of the location, depth, dip, and strike of the two deposits, information that was not available from the historical anomaly maps. The signal-to-noise ratio of the MEGATEM^II data is greater than the historical data, yielding more sharply defined anomalies.

The investigations also included a comparison between 90 Hz and 30 Hz MEGATEM^II data. The 90 Hz data were found to be useful for mapping the less conductive parts of the Iso body, whereas the 30 Hz data demonstrated that the New Insco body is more conductive.

Analysis of height attenuation data over the Iso body indicates that the body could be seen by the MEGATEM^II system if it were buried an additional 230 m deeper (in highly resistive material). On the other hand, the INPUT system would detect the Iso body only if it were buried no deeper than an additional 60 m. Tests with the transmitter turned off showed that, for this flight, the MEGATEM^II system noise levels on the processed data are about 300 pT/s.

Key Words: Geophysics • Airborne Electromagnetic survey • Iso • New Insco • Volcanogenic massive sulfide deposit • Rouyn-Noranda mining camp

This article has been cited by other articles:

				L.Z. Cheng, R.S. Smith, M. Allard, M. Chouteau, P. Keating, J. Lemieux, M.A. Vallee, D. Bois, and D .K. Fountain Geophysical Case Study of the Gallen Deposit, Quebec, Canada Exploration and Mining Geology, January 1, 2007; 16(1-2): 67 - 81. [Abstract] [Full Text] [PDF]

				D.R. LENTZ and S.R. McCUTCHEON The Brunswick No. 6 Massive Sulfide Deposit, Bathurst Mining Camp, Northern New Brunswick, Canada: A Synopsis of the Geology and Hydrothermal Alteration System Exploration and Mining Geology, July 1, 2006; 15(3-4): 1 - 34. [Abstract] [Full Text] [PDF]