Gulf of California
The Gulf of California is a prominent transtensional feature along the Pacific-North America plate boundary. The Gulf formed during Miocene time due to focused oblique rifting of the Baja California peninsula away from mainland Mexico.
My graduate research focused on assessing the role that rift obliquity played in the formation of the Gulf of California marine basin. I used detailed mapping, geochronology, and paleomagnetism of rift-related structures and volcanic/sedimentary basins to quantify the style and timing of early Pacific-North America plate boundary deformation.
Perspective view of the Gulf of California-Salton Trough oblique rift. Structures responsible for Miocene to Present plate boundary deformation are shown.
Geologic Mapping & Geochronology
Detailed geologic mapping coupled with high-precision geochronology and low-temperature thermochronology provides excellent constraints on the magnitude, timing, and structural style of faulting and related basin formation.
Citation: Bennett, S.E.K., Oskin, M.E., Dorsey, R.J., Iriondo, A., and Kunk, M. J., 2015, Stratigraphy and structural development of the southwest Isla Tiburón marine basin: Implications for latest Miocene tectonic opening and flooding of the northern Gulf of California, Geosphere, GES01153-1. [PDF]
Citation: Bennett, S.E.K., Oskin, M.E., Iriondo, A., and Kunk, M., J., 2016, Slip history of the La Cruz fault: development of a late Miocene transform in response to increased rift obliquity in the northern Gulf of California, Tectonophysics, Vol. 693, Part B, p. 409-435. [PDF]
View 3D Geologic Map of southern Isla Tiburón in Google Earth
Citation: Bennett, S.E.K., Oskin, M.E., Iriondo, A., and Kunk, M., J., 2016, Slip history of the La Cruz fault: development of a late Miocene transform in response to increased rift obliquity in the northern Gulf of California, Tectonophysics, Vol. 693, Part B, p. 409-435. [PDF]
Citation: Bennett, S.E.K., Oskin, M.E., and Iriondo, A., in review, Latest Miocene transtensional rifting of northeast Isla Tiburón, eastern margin of the Gulf of California, Tectonophysics special issue about the Gulf of California. [PDF]
Citations: Bennett, S.E.K., Oskin, M.E., and Iriondo, A., 2013, Transtensional Rifting in the Proto-Gulf of California Near Bahía Kino, Sonora, México, Geological Society of America Bulletin, v. 125, no. 11/12, p. 1752-1782. [PDF]
Bennett, Scott E.K., 2009, Transtensional Rifting in the Late Proto-Gulf of California Near Bahía Kino, Sonora, México, [M.S. Thesis]: University of North Carolina - Chapel Hill, 122 p. [Thesis PDF]
Paleomagnetism
Paleomagnetism of volcanic rocks provide clues to the magnitude, timing, and distribution of dextral shear related to Pacific-North America plate boundary deformation.
Citation: Bennett, S.E.K., and Oskin, M.E., 2014, Oblique Rifting Ruptures Continents: Example from the Gulf of California shear zone, Geology, v. 42, no. 3, p. 215-218. [PDF]
Tectonic Reconstructions
Synthesis of decades of geologic, geophysical, and geodetic research permits reconstruction of the Pacific-North America plate boundary in the Gulf of California and Salton Trough. Animated tectonic reconstructions are useful to visualize the evolution of plate boundary deformation.
Citation: Bennett, S.E.K., Darin, M.H., Dorsey, R.J., Skinner, L.A., Umhoefer, P.J., and Oskin, M.E., 2016, Animated Tectonic Reconstruction of the Lower Colorado River Region: Implications for Late Miocene to Present Deformation, in Reynolds, R.E. eds., Proceedings for the 2016 Desert Symposium. [PDF]