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McAbee Fossil Beds
The McAbee Fossil Beds is a Heritage Site that protects an Eocene Epoch fossil locality east of Cache Creek, British Columbia, Canada, just north of and visible from Provincial Highway 97 / the Trans-Canada Highway (Highway 1) at . The McAbee Fossil Beds, comprising , were officially designated a Provincial Heritage Site under British Columbia's Heritage Conservation Act on July 19, 2012.〔(McAbee fossil site receives heritage protection. )〕 The site is part of an old lake bed which was deposited about 52 million years ago and is internationally recognised for the diversity of plant, insect, and fish fossils found there. Similar fossil beds in Eocene lake sediments, also known for their well preserved plant, insect and fish fossils, are found at Driftwood Canyon Provincial Park near Smithers in northern British Columbia, on the Horsefly River near Quesnel in central British Columbia, and at Republic in Washington, USA. The Princeton Chert fossil beds in southern British Columbia are also Eocene, but primarily preserve an aquatic plant community.
== Palaeontology ==
Fossil plants from the same area as the McAbee fossil beds (Cache Creek and Kamloops B.C.) were first reported by G.M. Dawson.〔Dawson, G.M. (1877). "Report on explorations in the southern portion of British Columbia." ''Geological Survey of. Canada, Report of Progress for 1875–76'', pp. 233–265.〕 Palaeontological and geological studies of the McAbee Fossil Beds are more recent, however, going back at least to research in the 1960s and early 1970s by Dr. Len Hills of the University of Calgary and his students on the fossil spores and pollen (palynology) and the leaf fossils,〔Hills, L.V. 1965. Palynology and age of early Tertiary basins, interior British Columbia; unpubl. Ph.D. thesis, University of Alberta, Edmonton, Alberta, 189 p.〕〔Verschoor, K. van R. 1974. Paleobotany of the Tertiary (early Middle Eocene) McAbee Beds, British Columbia. M.Sc. thesis, University of Calgary, Calgary, AB, 128 p.〕 and research on the fossil fish from the fossil beds by Dr. Mark Wilson of the University of Alberta.〔 Thomas Ewing provided a detailed analysis of the geology of the Kamloops Group, including the McAbee beds. Significant research on the fossil plants and insects has only occurred since the late 1980s. The McAbee Fossil Beds are best known for the abundant and well preserved insect and fish fossils (''Amyzon'', ''Eohiodon'', and ''Eosalmo''). ''Eohiodon rosei'' from the McAbee Fossil Beds and other Eocene sites in British Columbia is now considered to belong to the present-day mooneye genus ''Hiodon''.
The climate of the McAbee Eocene lake setting was reconstructed to be temperate and wet, with a mean annual temperature about , winters lacking frost, and annual precipitation over a year.〔〔 The extraordinary detail preserved in the insect fossils, as well as the high diversity of insects, plants and other organisms means the McAbee Fossil Beds represent a Konservat-Lagerstätten.〔
A volcanic ash exposed in the lake shale beds was originally radiometrically dated using the K-Ar method at ~51 million years ago;〔〔 however, a recently provided radiometric date using the 40Ar-39Ar method places the McAbee Fossil Beds at 52.9 ± 0.83 million years old, placing it in the early Eocene Epoch.〔
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