New gravitational evidence for the subsurface extent of oceanic crust in north-central Newfoundland
Gravity has been measured at 226 locations having a mean spacing of 2.5 km in the area of western Notre Dame Bay, in north-central Newfoundland. The data reveal that the observed steep seaward positive gradients of the Bouguer anomalies previously found on eastern Notre Dame Bay continue to coastal...
| Published in: | Canadian Journal of Earth Sciences |
|---|---|
| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Canadian Science Publishing
1976
|
| Subjects: | |
| Online Access: | http://dx.doi.org/10.1139/e76-047 http://www.nrcresearchpress.com/doi/pdf/10.1139/e76-047 |
| Summary: | Gravity has been measured at 226 locations having a mean spacing of 2.5 km in the area of western Notre Dame Bay, in north-central Newfoundland. The data reveal that the observed steep seaward positive gradients of the Bouguer anomalies previously found on eastern Notre Dame Bay continue to coastal areas of western Notre Dame Bay. This belt of large gradients correlates spatially with the trace of the Chanceport – Lobster Cove Fault, which is the southern boundary of this belt of ophiolitic and island arc rocks (Belts Cove Ophiolite Complex) on the Burlington peninsula, which forms the basement of this belt. The observed anomalies may represent the gravity signature of a Paleozoic lithospheric plate margin, but a test of this possibility must await data from the bay itself.Interpretation of four profiles, using density data from rock samples and two-dimensional models, leads to the conclusion that oceanic crustal material similar to that found on Notre Dame Bay, zone D, continues inland beneath parts of zones C and E to 5–10 km maximum depth. The interpretation also suggests the desirability of establishing a subzone on the Burlington peninsula. |
|---|