GEOLOGIC MAPPING IN THE OZARK NATIONAL SCENIC RIVERWAYS, MISSOURI, AND VICINITY: U.S. GEOLOGICAL SURVEY AND NATIONAL PARK SERVICE COOPERATION

The U.S. Geological Survey (USGS) has conducted geologic mapping in the vicinity of the Ozark National Scenic Riverways (ONSR), Missouri, in partnership with the National Park Service (NPS) and other agencies since 1996. Most of the funding support for this work has come from the National Cooperative Geologic Mapping Program, with additional funding provided by the NPS Geologic Resources Division, the ONSR, Congressional line-item funds, and the U.S. Forest Service. Detailed geologic maps are complete in 18, 7.5-minute quadrangles. Additional mapping in 2007-2008 will complete geologic coverage of the entire ONSR, enabling the park to achieve its geologic inventory goal under the NPS geologic resource evaluation initiative. All of these maps have been, or will be, published as paper USGS Geologic Investigations Series maps and as GIS-based digital maps available via the internet. We are also publishing a comprehensive report together with a geologic map, at 1:100,000 scale for the area of the combined West Plains and Spring Valley, Missouri, 1:100,000 sheets with an adjoining strip of 7.5 minute quadrangles from the west edge of the adjacent Piedmont and Poplar Bluff 1:100,000 sheets. This area of approximately 4300 Mi² (11,116 Km²) encompasses most of the drainage basins for 2 of America's premier scenic rivers, the Current River and the Eleven Point River and the watersheds for several first magnitude karst springs. Geologic studies within the map area include research on: 1) Mesoproterozoic-age igneous basement rocks that are exposed as isolated knobs, 2) The stratigraphy and biostratigraphy of lower Paleozoic carbonates that comprise most of the bedrock, 3) The regional fault and fracture system and geohydrologic framework of the region, and 4) The speleogenesis of the caves and controls on development of karst. More information can be found at: http://geology.er.usgs.gov/eespteam/Karst/index.html and http://www.nps.gov/ozar/index.htm.