{"title":"Characterization of U(-V) Deposits in the La Sal District, UT and CO and Their Relationship to Paradox Basin Fluid Flow","authors":"Eytan Bos Orent, Mark D. Barton, Isabel F. Barton","doi":"10.1007/s42461-024-01062-7","DOIUrl":null,"url":null,"abstract":"<p>This paper synthesizes new and previous work on the tabular sandstone-hosted uranium and vanadium deposits of the La Sal district, one of the principal U-V districts of the Colorado Plateau. Deposits form a 1–3 km wide, E-W trending 30 km long trend spanning the Utah-Colorado border, approximately orthogonal to the Uravan belt. Ore is hosted in the uppermost fluvial subarkosic sandstones of the Salt Wash Member of the Jurassic Morrison Formation and typically forms channel-parallel, elongate orebodies up to 180 m long, 90 m wide, and 1 m thick. Sandstones are interbedded with silty, muddy, and calcareous units. Principal mineralogical changes include quartz overgrowths accompanied by destruction of early diagenetic hematite. Precipitation of compositionally distinct carbonate cements and clays followed. Bleaching was prior to and/or contemporaneous with mineralization, which is restricted to bleached rocks. Petrography shows that ore minerals (uraninite, coffinite, and montroseite) in part predate growth of authigenic quartz and calcite cements, followed by the formation of ferroan dolomites. Abundant V-rich phyllosilicates may reflect back-reaction of montroseite with quartz and other minerals. New U-Pb dating of ore-hosting calcite (~144 Ma) and K-Ar dating of V-clays (~42–36 Ma) parallel published results for elsewhere on the Plateau. Sedimentary structures (e.g., crossbedding), primary porosity, and the distribution of lithofacies in the local Salt Wash channel system control mineral growth. The thin section- to district-scale observations suggest that mineralization formed either by mixing of two fluids, or alternatively by reaction of oxidized fluids with a reductant earlier introduced during bleaching, as has been suggested in other Plateau deposits.</p>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":null,"pages":null},"PeriodicalIF":16.4000,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Accounts of Chemical Research","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1007/s42461-024-01062-7","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
This paper synthesizes new and previous work on the tabular sandstone-hosted uranium and vanadium deposits of the La Sal district, one of the principal U-V districts of the Colorado Plateau. Deposits form a 1–3 km wide, E-W trending 30 km long trend spanning the Utah-Colorado border, approximately orthogonal to the Uravan belt. Ore is hosted in the uppermost fluvial subarkosic sandstones of the Salt Wash Member of the Jurassic Morrison Formation and typically forms channel-parallel, elongate orebodies up to 180 m long, 90 m wide, and 1 m thick. Sandstones are interbedded with silty, muddy, and calcareous units. Principal mineralogical changes include quartz overgrowths accompanied by destruction of early diagenetic hematite. Precipitation of compositionally distinct carbonate cements and clays followed. Bleaching was prior to and/or contemporaneous with mineralization, which is restricted to bleached rocks. Petrography shows that ore minerals (uraninite, coffinite, and montroseite) in part predate growth of authigenic quartz and calcite cements, followed by the formation of ferroan dolomites. Abundant V-rich phyllosilicates may reflect back-reaction of montroseite with quartz and other minerals. New U-Pb dating of ore-hosting calcite (~144 Ma) and K-Ar dating of V-clays (~42–36 Ma) parallel published results for elsewhere on the Plateau. Sedimentary structures (e.g., crossbedding), primary porosity, and the distribution of lithofacies in the local Salt Wash channel system control mineral growth. The thin section- to district-scale observations suggest that mineralization formed either by mixing of two fluids, or alternatively by reaction of oxidized fluids with a reductant earlier introduced during bleaching, as has been suggested in other Plateau deposits.
期刊介绍:
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.