Exhumation Associated with Continental Strike-Slip Fault Systems

Geometry and timing of strike-slip and normal faults in the northern Walker Lane, northwestern Nevada and northeastern California: Strain partitioning or sequential extensional and strike-slip deformation? Available to Purchase
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Published:January 01, 2007
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CiteCitation
Christopher D. Henry, James E. Faulds, Craig M. dePolo, 2007. "Geometry and timing of strike-slip and normal faults in the northern Walker Lane, northwestern Nevada and northeastern California: Strain partitioning or sequential extensional and strike-slip deformation?", Exhumation Associated with Continental Strike-Slip Fault Systems, Sarah M. Roeske, Alison B. Till, David A. Foster, James C. Sample
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The Walker Lane, a zone of northwest-striking dextral faults east of the Sierra Nevada, accommodates 15%–25% of Pacific–North American plate motion. A distinctive feature of the Walker Lane is the coexistence of parallel dextral and normal faults, which either developed sequentially or are related by strain partitioning. In the northern Walker Lane, three en echelon dextral faults strike northwest parallel to relative motion between the Sierra Nevada and Great Basin. Each fault cuts major basins but is parallel to and 1–5 km basinward of range-front normal faults. Basins in this area have anomalous northwest trends, whereas basins and major normal faults in the adjoining Basin and Range province trend north to north-northeast. Major normal fault systems straddling the northern Walker Lane dip toward one another, thereby producing a structural low. Significant exhumation related to strike-slip faulting is restricted to one, more westerly striking, probably transpressional segment of one dextral fault.
Geologic data suggest that northwest-striking range-front faults were active during a ca. 3 Ma episode of extension but have been inactive in the Quaternary. Strike-slip faulting probably started immediately after 3 Ma, either cutting or reactivating deeper parts of the northwest-striking range-front normal faults as dextral faults. North-striking normal faults are active and kinematically compatible with the northwest-striking dextral faults.
The unusual northwest strike of normal faults in the northern Walker Lane may reflect reactivation of a major northwest-striking basement structure indicated by gravity data. Strain partitioning between parallel dextral and normal faults is unnecessary because the dextral faults parallel Sierra Nevada–Great Basin motion and can take up all required displacement. In contrast, Sierra Nevada–Great Basin motion in Owens Valley in the southern Walker Lane is strongly oblique to faults, so strain partitioning between parallel dextral and normal faults may be necessary.
- absolute age
- Ar/Ar
- Basin and Range Province
- California
- Cenozoic
- exhumation
- extension tectonics
- faults
- Great Basin
- igneous rocks
- Nevada
- normal faults
- North America
- Northern California
- oblique orientation
- preferred orientation
- Pyramid Lake
- pyroclastics
- shear zones
- Sierra Nevada
- stereographic projection
- strain
- strike-slip faults
- structural analysis
- tectonics
- United States
- volcanic rocks
- Walker Lane
- Virginia Mountains
- Dogskin Mountain
- Warm Springs fault zone
- Honey Lake fault zone