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194:. First described in 1892, this unit was not named until 1909 by Albert Homer Purdue in his study of the Ouachita Mountains of Arkansas. Purdue had initially named this unit the Caddo Shale at a 1907
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meeting, but later redefined and renamed the unit as the
Ouachita Shale. He again renamed the unit to the Blakely Sandstone in a letter to
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202:, to which Ulrich used in a 1911 publication, becoming the first reference using this name. Ulrich assigned the Blakely Mountain in
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Biostratigraphy of the
Paleozoic rocks of the Ouachita orogen, Arkansas, Oklahoma, west Texas
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547:"Structure and stratigraphy of the Ouachita Ordovician area, Arkansas (abstract)"
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214:. As of 2017, a reference section for this unit has yet to be designated.
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636:"Geology of the De Queen and Caddo Gap quadrangles, Arkansas"
528:
Annual Report of the
Geological Survey of Arkansas for 1890
526:
Griswold, L.S. (1892). "Whetstones and the novaculites".
684:
602:
Ethington, R.L.; Finney, S.C.; Repetski, J.E. (1989).
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List of fossiliferous stratigraphic units in
Arkansas
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Arkansas
Geological Commission Information Circular
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41:Blakely Sandstone (Coleman Quartz Mine, Arkansas)
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491:Bulletin of the Geological Society of America
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740:Ordovician southern paleotropical deposits
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745:United States geologic formation stubs
551:Geological Society of America Bulletin
634:Miser, Hugh D.; Purdue, A.H. (1929).
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487:"Revision of the Paleozoic systems"
444:"Stratigraphic summary of Arkansas"
683:. You can help Knowledge (XXG) by
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580:. Geological Survey of Arkansas.
402:
643:U.S. Geological Survey Bulletin
442:McFarland, John David (2004) .
730:Ordovician geology of Oklahoma
672:This article about a specific
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196:Geological Society of America
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679:in the United States is a
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210:, but did not designate a
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423:Paleontology in Arkansas
576:Purdue, A.H. (1909).
545:Purdue, A.H. (1909).
485:Ulrich, E.O. (1911).
457:: 19. Archived from
735:Ordovician Arkansas
563:10.1130/GSAB-19-513
512:10.1130/GSAB-22-281
503:1911GSAB...22..281U
410:Paleontology portal
200:Edward Oscar Ulrich
165:Albert Homer Purdue
25:Stratigraphic range
578:Slates of Arkansas
206:, Arkansas as the
184:Ouachita Mountains
180:geologic formation
153:Blakely Mountain,
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264:Leptochirognathus
173:Blakely Sandstone
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685:expanding it
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466:. Retrieved
459:the original
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389:Tetragraptus
387:
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369:G. echinatus
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328:Dichograptus
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304:P. aculeatus
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272:L. quadratus
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175:is a Middle
172:
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145:Type section
87:Mazarn Shale
77:Womble Shale
374:G. horridus
353:D. spinosus
320:Graptolites
288:P. costatus
240:C. horridus
724:Categories
497:(1): 677.
468:2018-01-08
429:References
248:Hisiodella
232:Cordylodus
218:Paleofauna
212:stratotype
177:Ordovician
157:, Arkansas
29:Ordovician
677:formation
343:D. euodes
224:Conodonts
150:Named for
110:Sandstone
101:Lithology
93:Thickness
73:Underlies
65:Sub-units
51:Formation
649:: 30–31.
396:See also
348:D. manus
312:Spinodus
296:Periodon
192:Oklahoma
188:Arkansas
162:Named by
129:Oklahoma
125:Arkansas
116:Location
83:Overlies
557:: 557.
499:Bibcode
182:in the
135:Country
106:Primary
57:Unit of
121:Region
639:(PDF)
462:(PDF)
447:(PDF)
681:stub
190:and
171:The
68:none
60:none
47:Type
647:808
559:doi
507:doi
186:of
726::
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641:.
614:^
586:^
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489:.
477:^
455:36
453:.
449:.
127:,
27::
712:e
705:t
698:v
687:.
608:.
565:.
561::
534:.
532:3
515:.
509::
501::
471:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
