| Title | Microscopic Planar Features in Quartz From Scollard Canyon, Alberta, and the Cretaceous - Tertiary Boundary Event |
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| Author | Grieve, R A F; Alexopoulos, J |
| Source | Canadian Journal of Earth Sciences vol. 25, no. 9, 1988 p. 1530-1534, https://doi.org/10.1139/e88-144 |
| Year | 1988 |
| Alt Series | Geological Survey of Canada, Contribution Series 26787 |
| Publisher | Canadian Science Publishing |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Alberta |
| NTS | 82P |
| Area | Scollard Area |
| Lat/Long WENS | -114.0000 -112.0000 52.0000 51.0000 |
| Subjects | extraterrestrial geology; mineralogy; sedimentology; quartz; clays; meteorite craters; iridium; microscopic analyses; sedimentary rocks; extinctions, biotic; Scollard Canyon Formation; Cretaceous;
Tertiary |
| Illustrations | photomicrographs |
| Released | 1988 09 01 |
| Abstract | Quartz grains separated from the Cretaceous-Tertiary (K/T) boundary clay at Scollard Canyon, Alberta, have prominent, microscopic planar features. These occur in 15 30% of the grains from the lower
1.5-cm of the boundary clay. They commonly correspond to the Ï and Ï orientations found at known meteorite impact sites and differ from deformation features produced by other dynamic geologic processes. Basal planar features, however, are absent here
and at other K/T sites. One possible explanation is that quartz at boundary sites is an incomplete sample of shocked quartz from the postulated K/T impact and unshocked detrital quartz. The source of the shocked quartz most likely was close to the
point of impact and near surface. This and previous isotopic data suggest the K/T target site contained a relatively thin upper unit of quartz-bearing crystalline rocks overlying basaltic material, corresponding possibly to thinned continent or a
continental margin. |
| GEOSCAN ID | 126515 |
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