Trace of Main Displacement Surface (Bedrock/Basin Fill Contact) of Pirate Fault Zone, West Flank of Santa Catalina Mountains, Pima and Pinal Counties, Arizona

Dickinson, William R.

dc.contributor.author	Dickinson, William R.
dc.date.accessioned	2018-11-10T01:09:36Z
dc.date.available	2018-11-10T01:09:36Z
dc.date.issued	1994-12-01
dc.identifier.citation	Dickinson, William R., 1994, Trace of Main Displacement Surface (Bedrock/Basin Fill Contact) of Pirate Fault Zone, West Flank of Santa Catalina Mountains, Pima and Pinal Counties, Arizona: Arizona Geological Survey Contributed Map CM-94-G, map scale 1:24,000, 10 p. and 1 map sheet.
dc.identifier.uri	http://hdl.handle.net/10150/630693
dc.description	The Pirate fault is a basin-range normal fault that separates footwall bedrock of the Santa Catalina Mountains on the east from downfaulted Neogene basin fill underlying Oro Valley, which forms a sedimented corridor to the west between the Santa Catalina and Tortolita Mountains (Pearthree and others, 1988). According to both McCullough (1963) and Budden (1975), this basin-margin, range-front structure was first termed the Pirate fault by Wallace (1954), although his own thesis makes no explicit claim for originating the nomenclature. The trend of the fault is northeasterly at the foot of Pusch Ridge near Tucson, but swings to nearly due north along the range front north of Catalina State Park. In detail, the structure is a complex fault zone, with brecciation and complex fracturing of varying intensity present for 100-200 m into footwall bedrock (Davis and others, 1994). By contrast, offset basin fill forming the hanging wall is little deformed, at least at exposed horizons. The contact between faulted basin fill and variably deformed bedrock is a thin gouge seam, only 1-5 cm thick, that dips consistently at angles of 50-55 degrees beneath Oro Valley. This contact is here inferred to be the main displacement surface of the Pirate fault zone, and its trace is the feature plotted along the trend of the fault. Adjacent to the gouge seam in the footwall is a cohesive sheet of compact fault breccia, composed of crushed bedrock and typically 4 m thick (Davis and others, 1994).
dc.language.iso	en
dc.publisher	Arizona Geological Survey (Tucson, AZ)
dc.relation.ispartofseries	CM-94-G
dc.relation.url	https://library.azgs.arizona.edu/
dc.rights	Arizona Geological Survey. All rights reserved.
dc.subject	Arizona Geological Survey Contributed Maps
dc.subject	Tertiary
dc.subject	Pinal County
dc.subject	Arizona
dc.subject	Pima County
dc.subject	Santa Catalina Mountains
dc.subject	map
dc.subject	Geology
dc.subject	Pirate Fault
dc.title	Trace of Main Displacement Surface (Bedrock/Basin Fill Contact) of Pirate Fault Zone, West Flank of Santa Catalina Mountains, Pima and Pinal Counties, Arizona
csdgm.bounding.west	-110.95
csdgm.bounding.east	-110.85
csdgm.bounding.north	32.6
csdgm.bounding.south	32.35
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	2018-11-10T01:09:36Z