Polk Creek Shale
From The Right Wiki
Jump to navigationJump to search
Polk Creek Shale | |
---|---|
Stratigraphic range: Ordovician | |
Type | Formation |
Unit of | none |
Sub-units | none |
Underlies | Blaylock Sandstone |
Overlies | Bigfork Chert |
Thickness | 50 to 225 feet[1] |
Lithology | |
Primary | Shale |
Location | |
Region | Arkansas, Oklahoma |
Country | United States |
Type section | |
Named for | Polk Creek, Montgomery County, Arkansas |
Named by | Albert Homer Purdue[2] |
The Polk Creek Shale is a Late Ordovician geologic formation in the Ouachita Mountains of Arkansas and Oklahoma. First described in 1892,[3] this unit was not named until 1909 by Albert Homer Purdue in his study of the Ouachita Mountains of Arkansas.[2] Purdue assigned Polk Creek in Montgomery County, Arkansas as the type locality, but did not designate a stratotype. As of 2017, a reference section for this unit has yet to be designated.
Paleofauna
Graptolites
- N. velatus[4]
See also
References
- ↑ McFarland, John David (2004) [1998]. "Stratigraphic summary of Arkansas" (PDF). Arkansas Geological Commission Information Circular. 36: 19. Archived from the original (PDF) on 2016-12-21. Retrieved 2018-01-09.
- ↑ 2.0 2.1 Purdue, A.H. (1909). Slates of Arkansas. Geological Survey of Arkansas. pp. 30, 35.
- ↑ Griswold, L.S. (1892). "Whetstones and the novaculites". Annual Report of the Geological Survey of Arkansas for 1890. 3.
- ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 Miser, Hugh D.; Purdue, A.H. (1929). "Geology of the De Queen and Caddo Gap quadrangles, Arkansas". U.S. Geological Survey Bulletin. 808: 40–42.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 Decker, Charles E. (1935). "Graptolites of the Sylvan Shale of Oklahoma and Polk Creek Shale of Arkansas". Journal of Paleontology. 9 (8).
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 Decker, Charles E. (1936). "Some tentative correlations on the basis of graptolites of Oklahoma and Arkansas". Bulletin of the American Association of Petroleum Geologists. 20 (3): 301–311.