GIS application in mineral resource analysis—A case study of offshore marine placer gold at Nome, Alaska

Geographic information system (GIS) technology has been applied to analyze the offshore marine placer gold deposits at Nome, Alaska. Two geodatabases, namely Integrated Geodatabase (IG) and Regularized 2.5D Geodatabase (R2.5DG), were created to store and integrate digital data sets in heterogeneous formats. The IG served as a data warehouse and used to manage various geological data, such as borehole, bedrock geology, surficial geology, and geochemical data. The R2.5DG was generated based on the IG and could be used for gold resource estimate at any given spatial domain. Information on placer gold deposits can be updated, queried, visualized, and analyzed by making use of these geodatabases. Ore body boundaries, gold distribution, and the resource estimation at various cutoff grades can be calculated in a timely manner. Based on the enhanced GIS architecture, a web-based GIS (http://uaf-db.uaf.edu/website/) was developed to facilitate remote users to access the offshore marine placer gold data. Users can integrate local data sources with remote data sources for query, visualization and analysis via a web browser. The GIS architecture developed in this project can be readily adapted to mineral resource management in other areas of the state.