The formation contains three members, which are as follows, in ascending stratigraphic order (lowest to highest):
Limestone & Siltstone Member: This member is the thinnest of the three, only getting up to 150 m (490 ft) thick in some areas, and is dominated by limemudstone. At the base of the member, it is entirely composed of shale, which gives way to calcareous sandstone, and then the common lime mudstones above that. Within these lime mudstones, there are occasional layers of more shale and chert.[1]
Shale Member: This member can get up to 250 m (820 ft) thick in some areas, and is, as the name suggests, entirely dominated by shale, which may be faulted and repeated in many places.[1]
Limestone & Chert Member: This member is the thickest of the three, getting up to 300 m (980 ft) thick in some areas, and contains a mixture of ribbon limestone, inter-bedded shales, as well as mega-breccia.[1]
The Emigrant Formation also contains lower Ordovician aged rocks above the Limestone & Chert Member, informally known as the "Platy Limestone Unit". This unit is primarily composed of fine-grained, platy limestone, which are inter-bedded with pale-red siltstone. The very top of the unit is not preserved, and contacts the overlying Palmetto Formation at a fault, and the unit itself is also difficult to age, although a lower Ordovician age is suggested, though more evidence will be needed to pinpoint the exact age of the unit. It has also been noted that this unit may represent a transitional bed between the Emigrant and Palmetto Formations.[3]
^ abcdefghijklmnopSundberg, Frederick A.; McCollum, Linda B. (September 2003). "Early and Mid Cambrian trilobites from the outer‐shelf deposits of Nevada and California, USA". Palaeontology. 46 (5): 945–986. doi:10.1111/1475-4983.00328.
^ abcdefghijklmnopqrstuvwxyzaaabacSundberg, Frederick A. (May 2018). "Trilobite biostratigraphy of the Cambrian 5 and Drumian stages, Series 3 (Laurentian Delamaran, Topazan, and Marjuman stages, Lincolnian Series) of the lower Emigrant Formation at Clayton Ridge, Esmeralda County, Nevada". Journal of Paleontology. 92 (S76): 1–44. doi:10.1017/jpa.2017.130.
^ abcdefgSkovsted, Christian B (1 April 2006). "Small shelly fossils from the basal Emigrant Formation (Cambrian, uppermost Dyeran Stage) of Split Mountain, Nevada". Canadian Journal of Earth Sciences. 43 (4): 487–496. doi:10.1139/e05-119.
^ abSun, Haijing; Babcock, Loren E.; Peng, Jin; Kastigar, Jessica M. (2 January 2017). "Systematics and palaeobiology of some Cambrian hyoliths from Guizhou, China, and Nevada, USA". Alcheringa: An Australasian Journal of Palaeontology. 41 (1): 79–100. doi:10.1080/03115518.2016.1184426.
^Skovsted, Christian B.; Peel, John S. (January 2011). "Hyolithellus in life position from the Lower Cambrian of North Greenland". Journal of Paleontology. 85 (1): 37–47. doi:10.1666/10-065.1.
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