The Mount Cap Formation is a geologic formation exposed in the Mackenzie Mountains, northern Canada. It was deposited in a shallow shelf setting in the late Early Cambrian,[1] and contains an array of Burgess Shale-type microfossils that have been recovered by acid maceration.[2]
The formation is 100 to 300 metres (330 to 980 ft), and comprises shales, siltstones and sandstones with a high glauconite content.[1] It has been exposed to remarkably little metamorphic activity given its great age; it is dated to the Bonnia–OlenellusTrilobite Zone.[1] This zone lies within the Lower Cambrian Waucoban stage in North America, which is equivalent to the Caerfai in Wales, and thus the Comley of England,[3] and has yet to be formally ratified. Nevertheless, this makes it just younger than the earliest trilobites,[dubious – discuss] and thus the earliest known Burgess Shale-type deposit, though this is disputable when considering the age of Chengjiang County fauna. Its organic-walled fauna, known as the "Little Bear biota", includes both non-mineralized and originally-mineralized taxa, including hyolith and trilobite fragments, anomalocaridid claws, arthropod carapaces and brachiopods.[4]
^ abcButterfield, N. J. (1994). "Burgess Shale-type fossils from a Lower Cambrian shallow-shelf sequence in northwestern Canada". Nature. 369 (6480): 477–479. Bibcode:1994Natur.369..477B. doi:10.1038/369477a0. S2CID 4326311.
^Harvey, T.; Butterfield, N. (2008). "Sophisticated particle-feeding in a large Early Cambrian crustacean". Nature. 452 (7189): 868–871. Bibcode:2008Natur.452..868H. doi:10.1038/nature06724. PMID 18337723. S2CID 4373816.
^Siveter, D. J.; Williams, M. (1995). "An early Cambrian assignment for the Caerfai Group of South Wales". Journal of the Geological Society. 152 (2): 221–224. Bibcode:1995JGSoc.152..221S. doi:10.1144/gsjgs.152.2.0221. S2CID 140607675.
^Butterfield, N. J.; Nicholas, C. J. (1996). "Burgess Shale-Type Preservation of Both Non-Mineralizing and 'Shelly' Cambrian Organisms from the Mackenzie Mountains, Northwestern Canada". Journal of Paleontology. 70 (6): 893–899. Bibcode:1996JPal...70..893B. doi:10.1017/S0022336000038579. JSTOR 1306492. S2CID 133427906.
External linksedit
Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Retrieved July 8, 2014.
April 10, 2024
mount, formation, mount, formation, geologic, formation, exposed, mackenzie, mountains, northern, canada, deposited, shallow, shelf, setting, late, early, cambrian, contains, array, burgess, shale, type, microfossils, that, have, been, recovered, acid, macerat. The Mount Cap Formation is a geologic formation exposed in the Mackenzie Mountains northern Canada It was deposited in a shallow shelf setting in the late Early Cambrian 1 and contains an array of Burgess Shale type microfossils that have been recovered by acid maceration 2 Mount Cap FormationStratigraphic range CambrianTypeFormationLithologyPrimaryShale siltstoneOtherSandstoneLocationCoordinates63 24 23 N 123 12 22 W 63 40639 N 123 20611 W 63 40639 123 20611RegionNorthwest TerritoriesCountry CanadaMount Cap formation Canada Contents 1 Description 2 See also 3 References 4 External linksDescription editThe formation is 100 to 300 metres 330 to 980 ft and comprises shales siltstones and sandstones with a high glauconite content 1 It has been exposed to remarkably little metamorphic activity given its great age it is dated to the Bonnia Olenellus Trilobite Zone 1 This zone lies within the Lower Cambrian Waucoban stage in North America which is equivalent to the Caerfai in Wales and thus the Comley of England 3 and has yet to be formally ratified Nevertheless this makes it just younger than the earliest trilobites dubious discuss and thus the earliest known Burgess Shale type deposit though this is disputable when considering the age of Chengjiang County fauna Its organic walled fauna known as the Little Bear biota includes both non mineralized and originally mineralized taxa including hyolith and trilobite fragments anomalocaridid claws arthropod carapaces and brachiopods 4 See also edit nbsp Earth sciences portal nbsp Canada portal nbsp Paleontology portalList of fossiliferous stratigraphic units in Northwest TerritoriesReferences edit a b c Butterfield N J 1994 Burgess Shale type fossils from a Lower Cambrian shallow shelf sequence in northwestern Canada Nature 369 6480 477 479 Bibcode 1994Natur 369 477B doi 10 1038 369477a0 S2CID 4326311 Harvey T Butterfield N 2008 Sophisticated particle feeding in a large Early Cambrian crustacean Nature 452 7189 868 871 Bibcode 2008Natur 452 868H doi 10 1038 nature06724 PMID 18337723 S2CID 4373816 Siveter D J Williams M 1995 An early Cambrian assignment for the Caerfai Group of South Wales Journal of the Geological Society 152 2 221 224 Bibcode 1995JGSoc 152 221S doi 10 1144 gsjgs 152 2 0221 S2CID 140607675 Butterfield N J Nicholas C J 1996 Burgess Shale Type Preservation of Both Non Mineralizing and Shelly Cambrian Organisms from the Mackenzie Mountains Northwestern Canada Journal of Paleontology 70 6 893 899 Bibcode 1996JPal 70 893B doi 10 1017 S0022336000038579 JSTOR 1306492 S2CID 133427906 External links editVarious Contributors to the Paleobiology Database Fossilworks Gateway to the Paleobiology Database Retrieved July 8 2014 Retrieved from https en wikipedia org w index php title Mount Cap formation amp oldid 1205828028, wikipedia, wiki, book, books, library,
