451:
463:
439:
427:
40:
512:
480:
496:
535:
370:
are perched above the top of the gray shales that Meek and Hayden named "Fort Benton". However, at their Fort Benton type location for the Benton Group, the Fort Hays
Limestone layer is hardly distinct from the Benton Shale and is identifiable only by its major change in fossil species.
593:"Descriptions of new Lower Silurian, (Primordial), Jurassic, Cretaceous, and Tertiary fossils, collected in Nebraska, by the exploring expedition under the command of Capt. Wm F. Reynolds, U.S. Top. Engineers, with some remarks on the rocks from which they were obtained"
742:
Tokay Tongue, however, is simply a synonym of the unit that Meek and Hayden (1861) long ago named the "Fort Benton group" (more commonly called Benton Group or Benton Shale ... and that has long been abandoned in favor of a more detailed lithostratigraphic
450:
462:
672:
Noblett, J.B.; Cohen, A.S.; Leonard, E.M.; Loeffler, B.M.; Gevirtzman, D.A. (1987). "The Garden of the Gods and basal
Phanerozoic nonconformity in and near Colorado Springs, Colorado.". In Beus, S.S. (ed.).
511:
438:
426:
479:
495:
548:
783:
are sawed into blocks, and employed in the construction of buildings. ... About eight miles west of Hays City there are about 60 feet exposed, of the
805:
39:
49:
830:
825:
358:, the distinction between the Benton and the Niobrara is very clear. This is near Meek and Hayden's type location for the Niobrara, the
766:. House Documents, otherwise Publ. as Executive Documents United States. Congress. House. Government Printing Office. pp. 66–69
406:
in the bentonite seams converts to rust when exposed to air resulting in orange lines across exposures of Benton shale and chalk.
835:
820:
292:
has also been used to refer to the chalky portions of the strata, especially the beds of the strata presently classified as
682:
592:
382:
correlates with the
Colorado Shale, and the Tokay Tongue of the lower Mancos is the synonym for the Benton Shale.
331:
Today, the Benton classification is obsolete in some regions, having been replaced by the ascending sequence
719:
391:
60:
is not as distinct from the Benton Shale as in the lower plains and these shales were later reclassified as
810:
815:
764:
Final
Reports of the United States Geological Survey of Nebraska and Portions of the Adjacent Territories
760:"IX. Sketch of the geological formations along the route of the Union Pacific Railway, Eastern Division"
707:. Denver, CO: Colorado Geological Survey and the Denver Museum of Nature & Science. p. sheet 1.
776:
755:
588:
419:
415:
367:
313:
214:
675:
Geological
Society of America Centennial Field Guide for the Rocky Mountain Section: Boulder, Colorado
343:. However, many old publications used the name. And the use of the Benton Group name continues in the
85:
316:
in 1862 to the gray marine shales, often chalky in the middle layers, lying above the terrestrial
759:
618:
553:
336:
65:
647:
648:"Stratigraphy and Depositional Environment of Greenhorn Limestone (Upper Cretaceous) of Kansas"
584:
309:
210:
572:
355:
363:
325:
200:
8:
717:
540:
502:
297:
293:
243:
69:
45:
780:
321:
135:
95:
57:
274:. In the "mile high" plains in the center of the continent, the named layers preserve
784:
678:
486:
340:
73:
671:
643:
614:
379:
348:
317:
285:
105:
395:
282:
654:(Bulletin 209). Kansas Geological Survey, University of Kansas, Lawrence, Kansas
625:(Bulletin 156). Kansas Geological Survey, University of Kansas, Lawrence, Kansas
718:
Spencer G. Lucas; W. John Nelson; Karl
Krainer; Scott D. Elrick (Spring 2019).
359:
332:
61:
799:
518:
27:
375:
259:
255:
165:
161:
344:
31:
754:
677:. Boulder, Colorado, Geological Society of America. p. 335-338.
399:
130:
703:
Raynolds, R.G. (2020). "MS-54 Cretaceous
Stratigraphy of Colorado".
271:
263:
173:
169:
366:
between
Yankton and the Niobrara River, high bluffs of near white
347:
where the
Graneros Shale, Greenhorn Limestone, Carlile Shale, and
278:
251:
247:
157:
153:
619:"Stratigraphy of the Carlile Shale (Upper Cretaceous) in Kansas"
64:. The Benton name was abandoned here in favor of subdivision as
16:
Geologic formation (shale) in
Montana, Wyoming, and other states
403:
390:
There are many thin beds of volcanic ash in the unit that have
267:
177:
398:. Taking its name from the formation, this material is called
328:, today a small city in Montana on the Upper Missouri River.
720:"The Cretaceous System in central Sierra County, New Mexico"
320:
and usually below the massive limestones at the base of the
597:
Academy of Natural Sciences of Philadelphia Proceedings
583:
456:
Concretionary cone-in-cone structures in Benton Shale
549:
List of fossiliferous stratigraphic units in Montana
530:
797:
665:
642:
613:
577:
52:adjoining Fort Benton, the type location of the
702:
324:. The name was taken from the type outcrop at
573:National Geologic Map Database - Geolex, USGS
696:
38:
705:Stratigraphic, Variable Scale. Map Series
56:. As seen in this image, the overlying
798:
806:Shale formations of the United States
354:In the lower Missouri River, west of
693:is in current use in this location.)
303:
787:of No. 2, of the Fort Benton Group.
468:Bentonite seams in the Benton Shale
351:may be recognized as member units.
13:
831:Cretaceous geology of South Dakota
826:Cretaceous geology of North Dakota
758:, United States Geologist (1871).
14:
847:
652:State Geological Survey of Kansas
623:State Geological Survey of Kansas
517:Chalk rhythmites in "old Benton"
501:Chalk rhythmites in "old Benton"
533:
510:
494:
485:Benton Group outcrop identified
478:
461:
449:
437:
425:
120:Shale, chalky shale, chalk beds
836:Cretaceous geology of Nebraska
748:
711:
636:
607:
566:
1:
821:Cretaceous geology of Wyoming
559:
385:
7:
526:
339:, Greenhorn Limestone, and
10:
852:
420:Colorado Springs, Colorado
416:Red Rock Canyon Open Space
409:
775:At Hays City the massive
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196:
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183:
149:
144:
124:
116:
111:
101:
91:
81:
37:
26:
21:
308:The name was applied by
554:Paleontology in Montana
244:geologic formation name
489:by F.V. Hayden in 1871
356:Yankton, South Dakota
246:historically used in
128:many bentonite seams,
50:Missouri River Breaks
364:Lewis and Clark Lake
201:Fort Benton, Montana
140:occasional sandstone
811:Cretaceous Colorado
541:Paleontology portal
368:Fort Hays Limestone
362:. On the shores of
337:Belle Fourche Shale
298:Fencepost limestone
296:, particularly the
294:Greenhorn Limestone
70:Greenhorn Limestone
66:Belle Fourche Shale
46:Cow Island, Montana
28:Stratigraphic range
816:Cretaceous Montana
727:New Mexico Geology
96:Niobrara Formation
58:Niobrara Formation
444:Gray Benton Shale
432:Gray Benton Shale
304:Naming and status
228:
227:
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790:
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752:
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644:Donald E. Hattin
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615:Donald E. Hattin
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543:
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521:member in Kansas
514:
505:member in Kansas
498:
482:
465:
453:
441:
429:
380:Colorado Plateau
349:Codell Sandstone
318:Dakota Sandstone
290:Benton Limestone
236:Benton Formation
106:Dakota Sandstone
44:Shale bluffs at
42:
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18:
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474:Other locations
469:
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445:
442:
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430:
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396:montmorillonite
388:
306:
283:Late Cretaceous
139:
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77:
17:
12:
11:
5:
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360:Niobrara River
333:Graneros Shale
322:Niobrara Chalk
305:
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62:Colorado Shale
43:
35:
34:
24:
23:
15:
9:
6:
4:
3:
2:
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684:0-8137-5402-X
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519:Lower Carlile
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341:Carlile Shale
338:
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187:United States
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74:Carlile Shale
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55:
51:
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41:
36:
33:
29:
25:
20:
777:rocky layers
774:
768:. Retrieved
763:
756:F. V. Hayden
750:
741:
735:. Retrieved
730:
726:
713:
704:
698:
691:Benton Group
690:
674:
667:
656:. Retrieved
651:
638:
627:. Retrieved
622:
609:
600:
596:
589:Hayden, F.V.
579:
568:
404:Iron sulfide
394:into mostly
389:
376:Mancos Shale
373:
353:
330:
314:Hayden, F.V.
307:
289:
275:
260:South Dakota
256:North Dakota
240:Benton Group
239:
235:
232:Benton Shale
231:
229:
221:Year defined
215:Hayden, F.V.
192:Type section
166:South Dakota
162:North Dakota
54:Benton Shale
53:
22:Benton Shale
743:terminology
392:devitrified
345:Front Range
326:Fort Benton
288:. The term
800:Categories
785:dark clays
770:2018-10-04
737:2022-06-12
658:2018-08-04
629:2018-08-04
603:: 415–447.
585:Meek, F.B.
560:References
310:Meek, F.B.
211:Meek, F.B.
131:septarians
32:Cretaceous
503:Greenhorn
487:in Kansas
400:bentonite
386:Bentonite
281:from the
197:Named for
112:Lithology
92:Underlies
86:Formation
646:(1962).
617:(1962).
591:(1862).
527:See also
272:Nebraska
264:Colorado
207:Named by
174:Nebraska
170:Colorado
145:Location
136:selenite
102:Overlies
733:(1): 10
410:Gallery
378:of the
279:fossils
252:Wyoming
248:Montana
242:) is a
184:Country
158:Wyoming
154:Montana
117:Primary
48:in the
681:
286:Period
276:marine
270:, and
268:Kansas
234:(also
178:Kansas
150:Region
72:, and
781:No. 3
723:(PDF)
125:Other
679:ISBN
374:The
312:and
230:The
224:1862
213:and
82:Type
779:of
238:or
802::
773:.
762:.
740:.
731:41
729:.
725:.
650:.
621:.
601:13
599:.
595:.
587:;
418:,
402:.
300:.
266:,
262:,
258:,
254:,
250:,
176:,
172:,
168:,
164:,
160:,
156:,
68:,
30::
689:(
687:.
661:.
632:.
335:/
138:,
133:,
76:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
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