Eldon Formation

{{short description|Geologic formation in Canada}}

{{Infobox rockunit

| name = Eldon Formation

| image = Mount-Yamnuska2-Szmurlo.jpg

| caption = The Eldon Formation forms the cliffs of Mount Yamnuska in Alberta

| type = Formation

| age = Middle Cambrian
~{{Fossil range|509|500}}

| prilithology = Limestone, dolomite

| otherlithology = Mudstone

| namedfor = Eldon Switch on the Canadian Pacific Railway in Banff National Park, Alberta

| namedby = Charles Doolittle Walcott in 1908Walcott, C.D. 1908. Nomenclature of some Cambrian Cordilleran formations. Smithsonian Miscellaneous Collections, vol. 53, no. 1, 14 pp.

| region = Canadian Rockies

| country = Canada

| coordinates = {{coord|51|18|8.5|N|115|55|45|W|name=Eldon Formation|display=inline,title}}

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| underlies = Pika Formation

| overlies = Stephen Formation, Snake Indian Formation

| thickness = Up to 500 metres (1640 ft)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}}.

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The Eldon Formation is a stratigraphic unit that is present on the western edge of the Western Canada Sedimentary Basin in the southern Canadian Rockies of southwestern Alberta and southeastern British Columbia.{{Cite web|url=http://ags.aer.ca/reports/atlas-of-the-western-canada-sedimentary-basin.htm|title=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|author=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|year=1994|accessdate=2018-07-13}} It is a thick sequence of massive, cliff-forming limestones and dolomites that was named for Eldon Switch on the Canadian Pacific Railway near Castle Mountain in Banff National Park by Charles Doolittle Walcott, who discovered the Burgess Shale fossils. The Eldon Formation was deposited during Middle Cambrian time, and it includes fossil stromatolites. The Eldon forms the scenic cliffs at the top of Castle Mountain, and can also be seen at Mount Yamnuska and other mountains in Banff and Yoho National Parks.Leckie, D.A. 2017. Rocks, ridges and rivers – Geological wonders of Banff, Yoho, and Jasper National Parks. Brokenpoplars, Calgary, Alberta, 217 pp. {{ISBN|978-0-9959082-0-8}}.