Department or Administrative Unit
The northern eastern California shear zone is an important component of the Pacific– North America plate boundary. This region of active transtensional deformation east of the San Andreas fault extends from the Garlock fault northward along the east side of the Sierra Nevada and into western Nevada. The eastern California shear zone is thought to accommodate nearly a quarter of relative plate motion between the Pacific and North America plates. Recent studies in the region, utilizing innovative methods such as cosmogenic nuclide geochronology, airborne lidar, structural mapping, and (U-Th)/He geochronology, are helping elucidate deformation histories for many of the major structures that comprise the eastern California shear zone. This field trip includes 12 stops focused on the active tectonics of the Sierra Nevada, Inyo Mountains, Coso Range, Poverty Hills, Volcanic Tableland, Fish Lake Valley, and Queen Valley. Trip participants will explore a rich record of the spatial and temporal tectonic evolution of the northern eastern California shear zone from the Miocene through the Holocene. Discussion will focus on the constancy of strain accumulation and release, timing of offset on faults, the origin and evolution of structures, distribution of strain, the various techniques used to determine fault displacements and slip rates, and the role and evolution of the eastern California shear zone as an increasingly important component of the Pacific–North America plate boundary.
Frankel, K.L., Lee, J., et al. (2010). Miocene-Quaternary tectonic evolution of the northern eastern California shear zone. In H.E. Clifton & R. Ingersol (Eds.), Geologic excursions in California and Nevada: Tectonics, stratigraphy, and hydrogeology (Book 108, 173-231). Upland, CA: Pacific Section, SEPM (Society for Sedimentary Geology.