Most geologists concerned with the tectonic framework of California believe that various assemblages of oceanic lithosphere, including island arcs, have been accreted to older sialic crust, mainly during Mesozoic time, resulting in a westward or oceanward growth of the state. During approximately the same time interval, great batholithic masses were also emplaced. The discrete geotectonic units that resulted from these events are characterized by specific types of metallic mineral deposits. Thus, geotectonic units and mineral deposit types are fairly well correlated in California, which should be of help to those planning exploration programs as well as to those concerned with estimating the mineral potential of large areas.
From the age, spatial, and genetic relation of various mineral deposit types to major geotectonic units it is concluded that (1) no simple mineral zoning exists with respect to the Sierra Nevada batholith, and (2) some types of deposits—massive sulfides, manganese, chromite, and mercury—are probably genetically related to the discrete geotectonic units in which they occur and are unrelated either to zoning around plutonic masses or to partial melting of a single subducting slab.
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Energy Resources of the Pacific Region
The energy and mineral resources of the vast Pacific basin and its neighboring land areas play a vital role in meeting the ever-growing needs of society worldwide. Building on the foundation of a highly successful conference held in 1978, this volume contains 51 of the 135 papers presented there. Subjects included are general and specific in nature--oil, gas, and coal resources; geothermal fields, uranium; tin; evaporites, trace elements; water resources; magma energy and fuels from magma. Geological and geophysical techniques, and also the new tool of remote sending for petroleum and minerals exploration are represented. Tectonics, structure fundamentals, subsurface hazards, international treaties and the law of the deep sea are discussed. Seventeen countries and regions are represented in these papers: Thailand, Nicaragua, the United States, Japan, Peru, Antarctica, El Salvador, Australia, Mexico, Taiwan, New Zealand, China, Chile, Indonesia, Canada, and the Pacific Ocean.