Geologic Map of the Little Horn Mountains 30' x 60' Quadrangle, Southwestern Arizona, Scale 1:100,000

Spencer, J.E.

dc.contributor.author	Spencer, J.E.
dc.date.accessioned	2018-11-13T23:26:25Z
dc.date.available	2018-11-13T23:26:25Z
dc.date.issued	1995
dc.identifier.citation	Spencer, J.E., 1995, Geologic Map of the Little Horn Mountains 30' x 60' Quadrangle, Southwestern Arizona, Scale 1:100,000. Arizona Geological Survey Open File Report, OFR-95-01, 1 map sheet, map scale 1:100,000, 10 p.
dc.identifier.uri	http://hdl.handle.net/10150/630934
dc.description	All Quaternary units except talus (Qt) and undivided surficial deposits (Qs) that are shown on the map were defined by Demsey (1990) and descriptions of these units given here are repeated verbatim or condensed from her report. Deposits were classified by Demsey based on the estimated time since the end of deposition, which was inferred based on degree of channel entrenchment, erosional degradation and rounding of channel margins, height of surfaces above channel bottoms, and degree of development of soils and desert varnish. Contacts between Quaternary map units and bedrock were determined by Demsey largely by aerial photograph analysis and were generalized so that they could be represented at 1: 100,000 scale. More recent detailed maps of bedrock, primarily at 1 :24,000 scale, show that many areas outlined as bedrock by Demsey are in fact Quaternary surficial deposits. It was thus necessary to assign Quaternary map units to areas of surficial deposits that were depicted as bedrock by Demsey (1990). These areas typically consist of canyon bottoms and flanking talus where various Quaternary units are complexly intermixed, and are commonly represented on this map as undivided surficial deposits (Qs). In other areas units identified by Demsey were extended to include adjacent areas previously depicted as bedrock, and in a few areas aerial photograph analysis was used to map previously unmapped surficial deposits.
dc.language.iso	en
dc.publisher	Arizona Geological Survey (Tucson, AZ)
dc.relation.ispartofseries	OFR-95-01
dc.relation.url	https://library.azgs.arizona.edu/item/AOFR-1552431515623-82
dc.rights	Arizona Geological Survey. All rights reserved.
dc.subject	Arizona Geological Survey Open File Reports
dc.subject	Quaternary
dc.subject	Southwestern Arizona
dc.subject	Little Horn Mountains
dc.subject	bedrock geology
dc.subject	surficial geology
dc.subject	Geology
dc.subject	geologic map
dc.subject	Lower Proterozoic
dc.subject	Paleozoic
dc.subject	cretaceous
dc.subject	Triassic
dc.subject	Mesozoic
dc.subject	Jurassic
dc.subject	Tertiary
dc.subject	Oligocene
dc.subject	Miocene
dc.subject	Pliocene
dc.subject	Pleistocene
dc.subject	Holocene
dc.subject	Yuma County
dc.subject	Maricopa County
dc.subject	Oatman Mountain
dc.subject	Painted Rock Mountains
dc.subject	Gila River
dc.subject	Dendora Valley
dc.subject	Painted Rock Dam
dc.subject	Painted Rock State Park
dc.subject	Yellow Medicine Wash
dc.subject	Palomas Plain
dc.subject	King Valley
dc.subject	North Star Mine
dc.subject	Clanton Hills
dc.subject	Clanton Well
dc.subject	geochronology
dc.subject	schist
dc.subject	gneiss
dc.subject	metavolcanics
dc.subject	metasedimentary
dc.subject	granitoids
dc.subject	intrusives
dc.subject	rock avalanche breccia
dc.subject	clastic sedimentary rocks
dc.subject	andesites
dc.subject	volcanic rocks
dc.subject	breccia
dc.subject	basalt
dc.subject	alluvium
dc.title	Geologic Map of the Little Horn Mountains 30' x 60' Quadrangle, Southwestern Arizona, Scale 1:100,000
csdgm.bounding.west	-114
csdgm.bounding.east	-113
csdgm.bounding.north	33.5
csdgm.bounding.south	33
dc.description.collectioninformation	Documents in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact azgs-info@email.arizona.edu.
refterms.dateFOA	2018-11-13T23:26:25Z