Thermal and barometric constraints on the intrusive and unroofing history ofthe Black Mountains: implications for timing, initial dip, and kinematics of detachment faulting in the Death Valley Region, California
Article Abstract:
Time-depth constraints on intrusion and unroofing during the Miocene are revealed by cooling age patterns and geobarometric data from the Black Mountains in Death Valley, California. Northwest diachronous cooling withdike intrusion show decreasing ages, suggesting a 10-15 km denudation along a northwest-oriented detachment system, with an average initial dip of 20 degress Footwall flexure migration under a scoop-shaped hanging wall block explains this northwestward unroofing and dike intrusion. A signifcant conclusion is that middle crust ductile fabrics steepen during unloading in the upper crust.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
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Paleomagnetic constraints on the initiation of uplift on the Santa Susana fault, western transverse ranges, California
Article Abstract:
A study of the accumulation of sediments on both sides of the Santa Susana Fault show Saugus and Pacoima formations were deposited from about 2.3 to 0.5 Ma. The Pacoima formations overlap the Saugus formations in the east Ventura basin. The presence of the 0. 76 Ma Bishop ash and magnetostratigraphy of Saugus and Pacoima strata reveals that the average sedimentation rate is 0.9 km/m.y. in the east Ventura basin and 1.1 km/m.y. in the northern San Fernando Valley. The accumulation of sediments on Santa Susana Fault has raised Santa Susana Mountains.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1993
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Kinematic evidence for extensional unroofing of the Fransiscan Complex along the Coast Range fault, Northern Diablo Range, California
Article Abstract:
The Del Puerto ophiolite in the northern Diablo Range, California is overlain by fault displacement-sheared Fransiscan metagraywacke. Coast Range ophiolite and Great Valley sequence attentuation was concurrent with the normal faulting and extensional offset representing the displacement. Moving westward across the underlying oceanic plate, the Fransiscan Complex lengthened and thinned due to subduction-caused instability. These movements resulted in blueschist facies alongside only slightly-metamorphic hanging wall units.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
User Contributions:
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