| Title | Quaternary stratigraphy and geomorphology of Charlie Lake [94A] map area, British Columbia |
| Download | Downloads |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Mathews, W H |
| Source | Geological Survey of Canada, Paper 76-20, 1978, 25 pages (1 sheet), https://doi.org/10.4095/104544  Open Access |
| Year | 1978 |
| Document | serial |
| Lang. | English |
| Maps | Publication contains 1 map |
| Map Info. | geological, 1:250,000 |
| Media | paper; on-line; digital |
| Related | This publication contains Surficial Geology, Charlie Lake,
Peace River District, British Columbia |
| File format | pdf |
| Province | British Columbia |
| NTS | 94A |
| Lat/Long WENS | -122.0000 -120.0000 57.0000 56.0000 |
| Subjects | surficial geology/geomorphology; stratigraphy; Nature and Environment; aggregates; alluvial fans; clays; depositional history; eolian deposits; glacial history; glaciation; gravels; kames; lacustrine
deposits; landslide deposits; meltwater channels; organic deposits; radiocarbon dates; silts; terraces; tills; Dunvegan Escarpment; Laurentide Ice-sheet; Animals; Quaternary |
| Illustrations | cross-sections, stratigraphic; cross-sections, structural; stratigraphic sections |
| Released | 1978 11 01; 2014 06 12 |
| Abstract | The Charlie Lake map-area lies at the western edge of the Great Plains and extends to within 10 miles of the Rocky Mountain Foothills. It is underlain by gently dipping Cretaceous sandstones and shales
which contribute to a subdued topography including northwesterly trending belts of hilly and lowland terrain. The Laurentide Ice Sheet reached the Charlie Lake area on at least three separate occasions during the Quaternary. Ice from the mountains to
the west also reached the area, with the last major mountain glaciation being essentially contemporaneous with the last Laurentide Glaciation. Occurrences of fluviatile gravels, similar in size distribution and provenance to those of the present
Peace River, are known at three different levels. The highest, about 1000 feet above Peace River, may be of preglacial age. The second, roughly 500 feet above Peace River, belongs to an early interglaciation; and the third, 100 to 200 feet above
Peace River, belongs to the last interglaciation. A radiocarbon date of 27 400 years B. P. is identified with this last unit. The two interglacial gravel units are each overlain by sands, silts, and clays attributable to aggradation and ponding of
Peace River by advancing Laurentide ice which ultimately covered these sediments with till. Sands and clays overlying the younger till were deposited in ice-dammed lakes during the retreating stages of Laurentide Glaciation. Isostatic tilting of the
shorelines of these lakes, which rise westerly at about 2 feet per mile, is attributed to rebound following a late retreat of the western glaciers. Postglacial entrenchment by Peace River has occurred to a depth of as much as 700 feet, and the
bedrock floor of this trench with its cover of modern flood plain gravels lies almost 200 feet lower than any earlier post-Cretaceous erosion surface. Incision to lesser depths has been produced by tributaries of Peace River. Quaternary history has
played an important role in controlling movement, storage, and availability of groundwater, in influencing landslides along river banks, in localizing supplies of gravel, as well as in perhaps affecting early postglacial migrations by animals and
man. |
| GEOSCAN ID | 104544 |
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