Geology And Mineral Resources Of Bonner County

Author : John E. Etienne
Publisher :
ISBN 13 :
Total Pages : 232 pages
Book Rating : 4.:/5 (176 download)

DOWNLOAD NOW!

Download or read book Geology and Mineral Resources of the Lightning Mountain, Rattle Creek Area, Eastern Bonner County, Idaho written by John E. Etienne and published by . This book was released on 1987 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This study focuses on the mapping and description of the rocks and mineralized areas in the Lightning Mountain- Rattle Creek area, in the Northeastern Idaho Panhandle. The low grade metamorphic rocks exposed have been assigned by earlier workers to the middle and upper part of the Prichard Formation, the oldest unit of the Precambrian Y Belt Supergroup. The top and base of the Prichard is not exposed in this area but 2845 m of argillites, siltites, and quartzites are present. This study subdivides the Prichard into four informal members, from oldest to youngest, the interbedded member, the argillite member, the upper interbedded member, and the laminated argillite member. The interbedded members consist of interbedded argillites, siltites, and quartzites. The argillite members consist of plane parallel laminated argillites and siltites. The igneous rocks in the area are intrusive and range from mafic to felsic. Precambrian Purcell sills and Cretaceous diabase dikes make up the mafic rocks. The felsic rocks are composed of a Cretaceous quartz monzonite stock and Cretaceous porphyritic quartz monzodioritic stocks and sills. Quarternary glacial drift covers large amounts of the study area and probably records both continental and alpine glaciation events. A glacial erratic found at the top of Rattle Mountain (elev. 1852.9 m) may record maximum thickness of continental glaciation in the study area. Mineral deposits in the study area are mostly lead- silver vein type, with galena and/or pyrite as the dominant sulfides. Exceptions are a Purcell sill-hosted copper vein, a stibnite-bearing vein, and an acanthite-bearing vein. Most of the deposits are interpreted to be of Mesozoic or Cenozoic age. The area shows promise for the discovery of more small sulfide-bearing veins. Nonmetallic resources consist mostly of gravel and flagstone deposits, which are used locally. The gravel is derived from glacial drift and the best flagstone occurs in the argillite layers of the upper interbedded member of the Prichard Formation"--Document.