113:
318:
290:
325:
297:
656:
632:
404:, and is separated from older units by a significant erosional surface. Radiometric ages range from 4.4 to 26.8 million years. The formation once formed an extensive thin veneer over the San Juan volcanic field before itself being eroded.
737:
Parker, D.F.; Ghosh, A.; Price, C.W.; Rinard, B.D.; Cullers, R.L.; Ren, M. (January 2005). "Origin of rhyolite by crustal melting and the nature of parental magmas in the
Oligocene Conejos Formation, San Juan Mountains, Colorado, USA".
396:
with only small quantities of volcanic rock of intermediate composition. The sequence reflects assimilation and fractional crystallization (AFC) of a primitive basalt magma. Total thickness is in excess of 1,200 feet (370 m).
599:
Bethke, P. M.; Barton, P. B.; Lanphere, M. A.; Steven, T. A. (1 October 1976). "Environment of ore deposition in the Creede mining district, San Juan
Mountains, Colorado; II, Age of mineralization".
679:
Lipman, Peter W.; Steven, Thomas A.; Mehnert, Harald H. (1970). "Volcanic
History of the San Juan Mountains, Colorado, as Indicated by Potassium–Argon Dating".
289:
812:
317:
112:
423:
The rich mineralization of the San Juan
Volcanic Field has been attributed to early intrusions of the Hinsdale Formation.
827:
822:
194:
187:
708:
Manley, Kim (1 December 1981). "Redefinition and description of the Los Pinos
Formation of north-central New Mexico".
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Geology and ore deposits near Lake City, Colorado: U.S. Geological Survey
Bulletin 478
801:
759:
243:
71:
29:
576:
769:"Geologic Map of the San Luis Hills Area, Conejos and Costilla Counties, Colorado"
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657:"A brief review of the geology of the San Juan region of southwestern Colorado"
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577:"Precambrian and Tertiary geology of Las Tablas quadrangle, New Mexico"
439:. Larsen redefined the unit as the Hinsdale Formation and included the
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33:
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The change to bimodal association coincided with the transition from
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extension, a pattern seen elsewhere in the western United States.
776:
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The formation was first named the
Hinsdale Volcanic Series by
443:. Barker removed the Los Pinos as its own formation in 1958.
701:
10.1130/0016-7606(1970)81[2329:VHOTSJ]2.0.CO;2
534:
730:
10.1130/0016-7606(1981)92<984:RADOTL>2.0.CO;2
581:
New Mexico Bureau of Mines and
Mineral Resources Bulletin
400:
The formation is the youngest volcanic formation of the
522:
117:
Hinsdale
Formation at its type locality in Colorado (
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366:of 4.4 to 26.8 million years, corresponding to the
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767:Thompson, Ren A.; Machette, Michael N. (1989).
740:Journal of Volcanology and Geothermal Research
635:. In Irving, J.D.; Bancroft, Howland (eds.).
8:
546:
633:"Geology of area near Lake City, Colorado"
324:
296:
111:
20:
452:
681:Geological Society of America Bulletin
558:
459:
304:Hinsdale Formation (the United States)
478:
7:
18:A geologic formation in New Mexico
14:
506:Lipman, Steven & Mehnert 1970
813:Neogene formations of New Mexico
760:10.1016/j.jvolgeores.2004.08.015
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295:
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661:U.S. Geological Survey Bulletin
1:
332:Hinsdale Formation (Colorado)
307:Show map of the United States
494:Thompson & Machette 1989
381:The Hinsdale Formation is a
621:10.2113/gsecongeo.71.6.1006
844:
383:bimodal volcanic formation
154:1,200 ft (370 m)
437:Hinsdale County, Colorado
435:in 1911 for exposures in
385:, containing silica-poor
282:
259:Hinsdale County, Colorado
110:
28:
427:History of investigation
354:exposed in southwestern
655:; Larsen, E.S. (1935).
547:Cross & Larsen 1935
402:San Juan volcanic field
575:Barker, Fred (1958).
433:Charles Whitman Cross
269:Charles Whitman Cross
123:Powderhorn Wilderness
335:Show map of Colorado
828:Rhyolite formations
823:Andesite formations
752:2005JVGR..139..185P
722:1981GSAB...92..984M
693:1970GSAB...81.2329L
613:1976EcGeo..71.1006B
206: /
145:Los Pinos Formation
30:Stratigraphic range
535:Bethke et al. 1976
523:Parker et al. 2005
352:geologic formation
348:Hinsdale Formation
210:37.787°N 107.319°W
24:Hinsdale Formation
818:Basalt formations
344:
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808:Neogene Colorado
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746:(3–4): 185–210.
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607:(6): 1006–1011.
601:Economic Geology
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441:Los Pinos Member
419:Economic geology
392:and high-silica
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787:. Retrieved
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710:GSA Bulletin
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668:. Retrieved
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347:
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275:Year defined
250:Type section
15:
687:(8): 2329.
559:Barker 1958
460:Manley 1981
377:Description
362:. It has a
213: /
201:107°19′08″W
188:Coordinates
119:Devils Lake
802:Categories
778:. I-1906.
569:References
479:Cross 1911
360:New Mexico
234:New Mexico
198:37°47′13″N
789:31 August
670:31 August
643:31 August
447:Footnotes
255:Named for
159:Lithology
151:Thickness
135:Formation
631:(1911).
409:Laramide
394:rhyolite
356:Colorado
265:Named by
230:Colorado
182:Location
176:rhyolite
172:andesite
141:Overlies
748:Bibcode
718:Bibcode
689:Bibcode
609:Bibcode
590:28 June
387:olivine
368:Neogene
240:Country
164:Primary
34:Neogene
390:basalt
371:period
226:Region
168:Basalt
772:(PDF)
350:is a
791:2020
672:2020
645:2020
592:2020
346:The
278:1911
131:Type
47:PreꞒ
780:doi
756:doi
744:139
726:doi
697:doi
665:843
617:doi
804::
774:.
754:.
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714:92
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695:.
685:81
683:.
663:.
659:.
615:.
605:71
603:.
585:45
583:.
579:.
513:^
486:^
467:^
373:.
174:,
170:,
121:,
97:Pg
41:Ma
32::
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125:)
102:N
92:K
87:J
82:T
77:P
72:C
67:D
62:S
57:O
52:Ꞓ
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
