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TitleGravity measurements in southern District of Keewatin and southeastern District of Mackenzie, N.W.T.
AuthorGibb, R A; Halliday, D W
SourceEarth Physics Branch, Gravity Map Series no. 124-131, 1974, 36 pages (8 sheets), (Open Access)
MapsPublication contains 8 maps
Map Info.geophysical, gravity, ground, 1:500,000
Mediapaper; on-line; digital
RelatedThis publication contains the following publications
File formatpdf
ProvinceNorthwest Territories; Nunavut
NTS55 /NE; 55 /NW; 55 /SW; 65 /NE; 65 /NW; 65 /SE; 65 /SW; 66 /SE; 66 /SW; 75 /SE; 75 /SW
Subjectsgeophysics; gravity interpretations; gravity surveys, ground; Churchill Province
Illustrationsgravity profiles
Released1974 01 01; 2018 11 13
AbstractA total of 3 ,464 gravity stations was used to compile eight Bouguer anomaly maps (1: 500,000) which cover part of the Western Churchill Province of the Canadian Shield in southern District of Keewatin and southeastern District of Mackenzie, Northwest Territories. Major negative anomalies in zones of high-level crust, characterized by abundant greenstones and greenschist to amphibolite facies metamorphism, are related to epizonal granitic plutons of Archean and Aphebian age. A prominent north northwesterly trending broad regional gravity low which cuts across the dominant northeasterly trends of the Province, contains a belt of "Nueltin Lake" type post-orogenic granite of late Hudsonian age. Gravity highs are related to basic volcanic and intrusive rocks and to areas of deep-level crust, characterized by granulite or retrograded granulite facies metamorphism, roots of batholiths and an absence of greens tones. The major feature of the gravity field, the Central Belt anomalies, crosses the area from south west to northeast. In this belt dominant gravity, magnetic, and geological trends are northeasterly and linear in sharp contrast to marginal zones on either side in which trends appear to "wrap around" the older Slave and Superior provinces of the Shield to the northwest and southeast. These differences in trend, along with differences in crustal level, metamorphism, plutonism and tectonic style may be related to a complex origin for Western Churchill Province by ancient plate interaction during Aphebian (Lower Proterozoic) time.