Bloyd Formation
| Bloyd Formation | |
|---|---|
| Stratigraphic range: Pennsylvanian | |
 Fossil from the Bloyd Formation | |
| Type | Formation |
| Sub-units | Baldwin coal,[1] Brentwood Member, Dye Shale Member, Kessler Limestone Member, Parthenon Sandstone Member,[2] and Woolsey Member[3] |
| Underlies | Atoka Formation |
| Overlies | Hale Formation |
| Lithology | |
| Primary | Shale |
| Other | Sandstone, limestone |
| Location | |
| Region | Arkansas |
| Country | United States |
| Type section | |
| Named for | Bloyd Mountain, Washington County, Arkansas[4] |
| Named by | Albert Homer Purdue |
The Bloyd Formation, or Bloyd Shale, is a geologic formation in Arkansas. It preserves fossils dating back to the Carboniferous period.
Stratigraphy
[edit]The Bloyd Formation conformably overlies the Hale Formation and unconformably underlies the Atoka Formation. Five formal and one informal members are recognized in the Bloyd Formation (in stratigraphic order):
- Kessler Limestone Member
- Dye Shale Member
- Parthenon Sandstone Member (also known as the "middle Bloyd sandstone")[5]
- Woolsey Member
- Baldwin coal (an informal unit at the top of the Woolsey Member)
- Brentwood Limestone Member
In the eastern parts of the Ozarks in Arkansas, the Bloyd Formation becomes undifferentiated with the underlying Hale Formation and is called the Witts Springs Formation.
Paleontology
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- A. missouiense[13]
- C. aliquantulus[13]
- G. minuta[13]
- S. spissa[13]
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- H. bassleri[14]
- H. sphaericum[16]
- S. hadra[16]
- V. ichnata[16]
- C. arkansanus[17]
- A. cordillerensis[13]
- C. laevis[13]
- P. strigosa[13]
See also
[edit]
References
[edit]- ^ Croneis, Carey (1930). "Geology of the Arkansas Paleozoic area" (PDF). Arkansas Geological Survey Bulletin. 3. Archived from the original (PDF) on 2017-01-25. Retrieved 2018-01-28.
- ^ Chandler, Angela; Zachry, Doy (2010). "Parthenon Sandstone: a prominent new member of the Morrowan Bloyd Formation, Pennsylvanian of north-central Arkansas (abstract)". Geological Society of America Abstracts with Programs. 42 (2): 70. Retrieved 28 January 2018.
- ^ McFarland, John David (2004) [1998]. "Stratigraphic summary of Arkansas" (PDF). Arkansas Geological Survey Information Circular. 36: 14. Archived from the original (PDF) on 2016-12-21. Retrieved 2018-01-28.
- ^ Purdue, A. (1907). "Description of the Winslow quadrangle". U.S. Geological Survey Geologic Atlas of the United States. 154: 2, 3.
- ^ Chandler, Angela; Zachry, Doy (2010). "Parthenon Sandstone: a prominent new member of the Morrowan Bloyd Formation, Pennsylvanian of north-central Arkansas". Geological Society of America Abstracts with Programs. 42 (2): 70. Retrieved 27 May 2018.
- ^ a b c d e f g Henry, Thomas W.; Sutherland, Patrick K. (1977). "Brachiopod biostratigraphy of Morrowan series (Pennsylvanian) in northwestern Arkansas and northeastern Oklahoma" (PDF). Oklahoma Geological Survey Guidebook. 18: 107–115. Retrieved 1 February 2018.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab Horowitz, Alan S. (1977). "Late Mississippian and Early Pennsylvanian bryozoan faunas of Arkansas and Oklahoma: a review" (PDF). Oklahoma Geological Survey Guidebook. 18: 101–105. Retrieved 3 February 2018.
- ^ a b c d e f g h i j k l m n o p Nodine-Zeller, Doris E. (1977). "Microfauna from Chesterian (Mississippian) and Morrowan (Pennsylvanian) rocks in Washington County, Arkansas, and Adair and Muskogee Counties, Oklahoma" (PDF). Oklahoma Geological Survey Guidebook. 18: 89–99. Retrieved 3 February 2018.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x Saunders, W. Bruce; Manger, Walter L.; Gordon Jr., Mackenzie (1977). "Upper Mississippian and Lower and Middle Pennsylvanian ammonoid biostratigraphy of northern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 117–137. Retrieved 1 February 2018.
- ^ a b c d e f g h i j k l m n o p q r s Gordon, Jr., Mackenzie (1964). "Carboniferous cephalopods of Arkansas" (PDF). U.S. Geological Survey Professional Paper. 460: 40–45.
- ^ a b c d e f g h i j k Grayson Jr, Robert C.; Sutherland, Patrick K. (1977). "Conodont evidence for unconformity within Trace Creek Shale Member of Bloyd Formation (Lower Pennsylvanian) in northwestern Arkansas and northeastern Oklahoma" (PDF). Oklahoma Geological Survey Guidebook. 18: 181–184. Retrieved 30 January 2018.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am an ao ap aq ar as at au av aw ax ay az ba bb bc bd be bf bg bh Strimple, Harrell L. (1977). "Chesterian (Upper Mississippian) and Morrowan (Lower Pennsylvanian) crinoids of northeastern Oklahoma and northwestern Arkansas" (PDF). Oklahoma Geological Survey Guidebook. 18: 171–176. Retrieved 30 January 2018.
- ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af Groves, John R. (1983). "Calcareous foraminifers and algae from the type Morrowan (Lower Pennsylvanian) region of northeastern Oklahoma and northwestern Arkansas" (PDF). Oklahoma Geological Survey Bulletin. 133: 65. Retrieved 3 February 2018.
- ^ a b c d e f Knox, Larry W. (1977). "Morrowan (Lower Pennsylvanian) ostracodes from Arkansas and Oklahoma" (PDF). Oklahoma Geological Survey Guidebook. 18: 139–147. Retrieved 31 January 2018.
- ^ a b c d Sohn, I. G. (1977). "Late Mississippian and Early Pennsylvanian ostracoda from northern Arkansas - a preliminary survey" (PDF). Oklahoma Geological Survey Guidebook. 18: 149–159. Retrieved 31 January 2018.
- ^ a b c Rigby, J. Keith; Manger, Walter L. (14 July 2015). "Morrowan lithistid demosponges and hexactinellids from the Ozark Mountains of northwestern Arkansas". Journal of Paleontology. 68 (4): 734–746. doi:10.1017/S0022336000026184. S2CID 131850370.
- ^ Branson, Carl C. (May 1961). "New records of the Scyphomedusan Conostichus" (PDF). Oklahoma Geology Notes. 21 (5): 130–138. Retrieved 28 January 2018.
- Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Retrieved 17 December 2021.