Regional-scale magnetotelluric survey of the Yellowknife fault

Garcia, X.* and Jones, A.G. Geological Survey of Canada, 615 Booth St., 
Room 208, Ottawa, Ontario, Canada. K1A 0E9.


Abstract

During the 1996 Lithoprobe magnetotelluric, MT, survey measurements were 
made at sites from west of Yellowknife -Northwest Territories, Canada-
across the Yellowknife fault to the east. The 2D interpretation of this 
profile showed the most anomalous response at the site located north of 
Yellowknife virtually on the Yellowknife fault.

The first MT study carried out during winter 2000 have been located 10 km 
north of the previous profile, on a profile extending 20 km with variable 
station spacing from the Yellowknife fault. The main objective of this 
study is the study of the Yellowknife fault as a regional feature and the 
possible relation of the enhanced conductivity with the gold deposits.

The second MT study realized in the area consisted of two short AMT profiles 
located south of the city of Yellowknife, close to the Kamex islands. The 
first profile consists on 8 stations and is located over a shear zone that 
contains a gold deposit. The second one consists on 5 stations and is 
located south of the first profile over the same shear zone where no mineral 
has been found. Different geophysical studies realized in the area failed 
to locate the mineral deposit. The main objective of this study is whether 
the MT method is valid to locate gold deposits in the Yellowknife area and 
an understanding of this shear zone and its relation with the Yellowknife fault.

In this work we present the 2D modeling of these three profiles.