Southern California Bight Undifferentiated Rock

This dataset represents the state of knowledge about the distribution of undifferentiated rocks along the Southern California continental shelf as of 1974. The data are derived from a single, paper map. The purpose of this project was to create digital, GIS format versions of the California continetnal shelf seafloor substrate using existing hard copy (paper) maps from a variety of sources. Created using map from US Department of Interior, Bureau of Land Management, Pacific Outer Continental Shelf Office, 1974. The map illustrates 8 substrate types which we distilled into three: Sedimentary Rocks, Undifferentiated Rocks, and Vulcanic Metamorphic Rocks. Original 8 substypes were: Pre-upper Cretaceous sedimentary igneous & metamorphic rocks; Eocene & Paleocene sedimentary rocks; Miocene vulcanic rocks; Oligocene sedimentary rocks (non-marine); Miocene intrusive igneous rocks & pre-upper cretaceous igneous; sedimentary and metamorphic rocks (undifferentiated); Miocene igneous & sedimentary rocks (undifferentiated); Holocene Pleistocene & Plicene sediments and sedimentary rocks; and Miocene sedimentary rocks. Data digitized from Channel Islands Area Map created by the US Department of the Interior Beurea of Land Management, Pacific Continental Shelf Office, 1974. UCSB library call number: 9507, .N2446, 1974, .U5, graphic #11. Source data from the map were prepared by the U.S. Geological Survey, 1974 (Geologic Division).