Neogene folding and faulting in southern Monterey Bay

Structures in southern Monterey Bay reflect Neogene tectonic activity; folding and faulting are confined to strata of the Middle Miocene and younger. Structures strike almost perpendicular to one another and exhibit compressional tectonic characteristics such as thrust faulting, reverse faulting and asymmetrical folding. Shallow Mesozoic basement rocks outcrop at or near the surface in most of the region and form a decollement along which the Miocene Monterey Formation has decoupled and been folded. Wrench fault tectonics complicated by compression, gradual uplift of the basement rocks, and a change in plate convergence direction is responsible for the observed structures in southern Monterey Bay.