Tectonic setting of Faulted Tertiary strata associated with the Catalina core complex in southern Arizona
KeywordsArizona Geological Survey Contributed Reports
Basin and Range Province
Dripping Spring Mountains
Santa Catalina Mountains
San Pedro Trough
San Manuel Formation
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CitationDickinson, W.R., 1991, Tectonic setting of Faulted Tertiary strata associated with the Catalina core complex in southern Arizona: Arizona Geological Survey Contributed Report by the Geological Society of America, GSA Special Paper 264, 115 p.
DescriptionStratigraphic and structural relations of syntectonic sedimentary sequences associated with Cordilleran metamorphic core complexes provide valuable information about the style and timing of extensional deformation related to tectonic denudation. Adjacent to the Catalina core complex, the San Pedro trough and other nearby depocenters contain multiple tilted half-grabens of conglomeratic mid-Tertiary strata partly buried beneath Neogene basin fill. Major episodes of local geologic history included mid-Proterozoic construction of continental crust, subsequent but intermittent platform sedimentation extending through Paleozoic time, mid-Mesozoic initiation of arc magmatism that persisted at intervals through mid-Tertiary time, complex Laramide orogenic deformation of latest Cretaceous to early Tertiary age, and Cenozoic extensional deformation involving both mid-Tertiary and basin-range phases of development. Precambrian basement includes lower Proterozoic Pinal Schist intruded by voluminous lower to middle Proterozoic granitic plutons. Pre-Laramide stratigraphic cover includes middle Proterozoic sedimentary strata and intercalated diabase sills, Paleozoic carbonate and clastic units, and Mesozoic volcaniclastic and clastic successions. Laramide assemblages include metaluminous plutons and andesitic to rhyolitic volcanic fields, synorogenic nonmarine sedimentary sequences, and large bodies of peraluminous two-mica granite. Laramide structural features include both premetamorphic and ductile synmetamorphic thrusts within the Catalina core complex, brittle thrusts of uncertain vergence and overall configuration outside the Catalina core complex, and folds of varied geometry related in part to local thrusts exposed nearby. Paleogene erosion had stripped Laramide volcanic cover from wide areas by mid-Tertiary time.
Series/Report no.GSA Special Paper 264
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