| Title | Sedimentology and stratigraphy of the Lower Clastic Unit of the Cambrian, Northwest Victoria Island |
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| Author | Durbano, A; Pratt, B; Hadlari, T ; Dewing, K |
| Source | 38th annual Yellowknife geoscience forum, abstracts of talks and posters; 2010 p. 73-74 |
| Links | Online - En ligne
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| Image |  |
| Year | 2010 |
| Alt Series | Natural Resources Canada, Contribution Series 20230225 |
| Publisher | Northwest Territories Geological Survey |
| Meeting | Annual Yellowknife Geoscience Forum; Yellowknife; CA; November 16-18, 2010 |
| Document | serial |
| Lang. | English |
| Media | paper; digital; on-line |
| File format | pdf |
| Province | Northwest Territories |
| NTS | 67C; 67F; 67G; 77; 78A; 78B; 78C; 78D; 87; 88A; 88B; 88C; 88D |
| Area | Victoria Island |
| Lat/Long WENS | -120.0000 -100.0000 74.0000 68.0000 |
| Subjects | general geology; stratigraphy; sedimentology; Cambrian |
| Program | GEM: Geo-mapping for Energy and Minerals Sverdrup Sedimentary Basin |
| Released | 2010 11 16 |
| Abstract | (unpublished)
The Paleozoic rocks of Victoria Island have only been studied at regional scale. In an effort to improve the knowledge of the stratigraphy we completed a two-week study focusing
on the basal clastic unit of the Cambrian strata. The main study area, near Minto Inlet on northwestern Victoria Island, was a river cut section with six well exposed outcrop faces. Each section was measured in bed-by-bed detail and photo mosaics
were taken in an effort to discern sedimentary processes and depositional history.74 In the study area 80 metres of clastic strata rest unconformably over a Franklin gabbro sill that has intruded the Minto Inlet Formation. The stratigraphy consists
of alternating packages of bioturbated and cross-bedded sandstones throughout the clastic unit, with some shale and siltstone periodically interbedded with the sandstones in fining upward successions. The typical facies include coarse grained
moderately sorted sandstone with large cross-bedding, medium grained well sorted sandstone with parallel bedding and cross bedding, weak to strongly bioturbated medium grained sandstone with intermittent fine parallel laminated shale beds, and
bioturbated fine to medium grained recessive sandstone with nodular weathering and occasional parallel lamination. Alternation of bioturbated and cross-bedded sandstones along with reactivation surfaces suggests a tidally influenced shoreline
environment. One of our goals is to correlate the Victoria Island stratigraphy to the mainland. The Cambrian beds of the Northern Interior Plains were deposited on the Lac Des Bois and Blackwater platforms, the depositional setting recognized as a
semi-enclosed epicontinental marine basin. The three main stratigraphic units include the Mount Clark, Mount Cap and the Saline River formations. The Mount Clark Formation is a fine to coarse grained transgressive sandstone that rests unconformably
on Proterozoic or Archean rocks. The Mount Cap Formation is made up of low energy deposits of clays and carbonate muds. An unconformity at the top of the Mount Cap Formation was created by relative sea-level drop. The Saline River Formation was
deposited in restricted marine conditions and contains clays, carbonate muds and evaporite deposits. The Lower clastic unit of the Cambrian on Victoria Island correlates well with the Mount Clark Formation due to similarity of lithology (cross-bedded
and bioturbated sandstones) and age of the units determined from trilobites as Early to Middle Cambrian. The unit overlying the basal clastic unit of the Cambrian strata consisted of shale and large beds of carbonate mudstone, which correlate to the
Mount Cap Formation. |
| GEOSCAN ID | 332131 |
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