Role of the Eastern California Shear Zone in accommodating Pacific-North American Plate motion
Abstract
The newly recognized Eastern California shear zone (ECSZ) of the Mojave Desert-Death Valley region has played a major, but previously underappreciated role in accommodating the dextral shear between the Pacific and North American plates in late Cenozoic time. Comparison of integrated net slip along the shear zone with motion values across the entire transform boundary indicates that between 9% and 23% of the total relative plate motion has occurred along the ECSZ since its probable inception ∼10-6 Ma. Long-term integrated shear along the ECSZ (6-12 mm yr-1) is similar to historic measurements (6.7±1.3 mm yr-1). Time-space patterns of faulting suggest that shear was concentrated in the eastern part of the Mojave Desert block and Death Valley during late Miocene and early Pleistocene time, but that the locus of faulting in the south-central Mojave jumped westward between 1.5 and 0.7 Ma.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- August 1990
- DOI:
- 10.1029/GL017i009p01323
- Bibcode:
- 1990GeoRL..17.1323D
- Keywords:
-
- Tectonophysics: Plate motions;
- past and present;
- Information Related to Geographic Region: Pacific Ocean;
- Information Related to Geographic Region: North America;
- Marine Geology and Geophysics: Plate tectonics;
- Tectonophysics: Continental tectonics;
- Tectonophysics: Plate boundary structures and processes