Earlie Formation

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Earlie Formation
Stratigraphic range: Middle Cambrian
~509–500 Ma
TypeFormation
UnderliesPika Formation, Deadwood Formation
OverliesBasal sandstone unit
ThicknessUp to 172 metres (565 ft)[1]
Lithology
PrimarySiltstone, sandstone, shale
Location
Coordinates53°10′49″N 110°25′47″W / 53.18028°N 110.42972°W / 53.18028; -110.42972 (Earlie Formation)Coordinates: 53°10′49″N 110°25′47″W / 53.18028°N 110.42972°W / 53.18028; -110.42972 (Earlie Formation)
RegionCanadian Rockies
Country Canada
Type section
Named forEarlie Lake, Alberta
Named byD.C. Pugh[1]

The Earlie Formation is a stratigraphic unit of Middle Cambrian age in the Western Canada Sedimentary Basin that is present beneath the plains of Alberta and eastern Saskatchewan.[1][2] It was named for Earlie Lake in the County of Vermilion River, Alberta, by D.C. Pugh in 1971, who described the type section based on data from an oil well drilled in that area.[1][3]

Lithology[]

The Earlie Formation consists of interbedded glauconitic siltstones and fine-grained sandstones and shales.[1][3] The presence of glauconite indicates that the sediments were deposited in a marine environment.[4]

Deposition and stratigraphic relationships[]

The Earlie Formation underlies the plains of Alberta and eastern Saskatchewan. It rests conformably on the unnamed basal sandstone unit that was deposited on the Precambrian rocks of the North American Craton at the start of a marine transgression of that area. It is overlain by the Pika Formation or, in areas where the Pika is not present, by the Deadwood Formation. It thickens to the west where it grades into the Mount Whyte, Cathedral, Stephen, and Pika Formations. It thins eastward to zero in Saskatchewan.[2][3][5]

References[]

  1. ^ Jump up to: a b c d e Pugh, D.C. 1971. Subsurface Cambrian stratigraphy in southern and central Alberta. Geological Survey of Canada, Paper 70-10.
  2. ^ Jump up to: a b Slind, O.L., Andrews, G.D., Murray, D.L., Norford, B.S., Paterson, D.F., Salas, C.J., and Tawadros, E.E., Canadian Society of Petroleum Geologists and Alberta Geological Survey (1994). "The Geological Atlas of the Western Canada Sedimentary Basin (Mossop, G.D. and Shetsen, I., compilers), Chapter 8: Middle Cambrian and Early Ordovician Strata of the Western Canada Sedimentary Basin". Retrieved 2018-07-13.CS1 maint: multiple names: authors list (link)
  3. ^ Jump up to: a b c Glass, D.J. (editor) 1997. Lexicon of Canadian Stratigraphy, vol. 4, Western Canada including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba. Canadian Society of Petroleum Geologists, Calgary, 1423 p. on CD-ROM. ISBN 0-920230-23-7.
  4. ^ Chafetz, H.S. and Reid, A. 2000. Syndepositional shallow-water precipitation of glauconitic minerals. Sedimentary Geology, vol. 136, p. 29-42.
  5. ^ Alberta Geological Survey, 2013. "Alberta Table of Formations; Alberta Energy Regulator". Retrieved 1 May 2018.
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