DETAILED GEOLOGIC MAPS OF THE NORTHERN CALICO MOUNTAINS AND THE LANE MOUNTAIN AREA, CENTRAL MOJAVE DESERT CALIFORNIA: PART 1 THE NEED FOR NEW MAPPING

Enigmatic rocks in the north Calico Mountains and Lane Mountain north of Barstow have long intrigued geologists. The Lane Mountain 15' quad was mapped by McCulloh in the 1950s, who recognized sequences of metasedimentary rocks of assumed Paleozoic and Mesozoic age, Mesozoic plutonic rocks, and Tertiary volcanic rocks and sediments. McCulloh's mapping was small scale and did not display detailed stratigraphic or structural data. More recent synthesis refer to McCulloh's mapping, but there are no new maps of the north Calico Mountains or the Lane Mountain area. Geology is referenced in the literature, but no new published mapping of the Paleozoic, Mesozoic or Cenozoic rocks has been done for >60 years.

Regional synthesis during the 1980es recognized Paleozoic metasedimentary rocks north of Lane Mountain differ from shallow water cratonal-miogeoclinal Paleozoic metasedimentary sequences in the Mojave region. Cambrian thru Ordovician deep water Paleozoic rocks correlated with rocks of the Antler orogenic belt of central Nevada were recognized. Overlap sequence of Mississippian synorogenic rocks deposited on top of the older deep water rocks, and off shore deposits of Pennsylvanian and Permian age deposited on the older overlap and deepwater sediments were recognized in the El Paso Mountains (Carr and others 1992, Carr and others 1997) and several other ranges (Miller and Sutter 1982), and have been called the "Northwest Mojave Terrane". Mesozoic age post orogenic rocks are postulated to have been deposited on the exposed and eroded older rocks (McCulloh) and younger Miocene volcanic and sedimentary rocks were deposited in local basins.

New detailed mapping of the north Calico Mountains and the Lane Mountain area within the context of modern regional framework allows resolution of stratigraphy and structure and a more clear and complete geologic picture to be defined. Old 15' maps have been replaced with 7.5' quads, Google Earth air photos allow good resolution, and GPS allows more accurate locations. The mapped area covers portions of the Lane Mountain, Williams Well and Coyote Lake 7.5'Quads. Large scale mapping at 1:6,000 scale depicts and resolves complex stratigraphic and structural details of Paleozoic, Mesozoic, and Cenozoic rocks in the mapped area within the context of prevailing regional framework.