The development and use of digital cartographic data bases

Abstract

The increasing demand of the Nation's natural resources developers for storage, retrieval, manipulation, analysis, and display of large quantities3 of earth science data have necessitated the use of computers and the building of sophisticated computer information systems. As the needs of resource managers and analysts were identified, it becomes obvious that cartographic data in digital form were required. The Geological Survey is gathering digital cartographic data in several forms including base category data (such as boundaries, hydrography, transportation, etc.), elevation data, and land use and land cover data to meet these and other needs. As we gather data, we are beginning to identify some of the problems unique to organizing cartographic data in form suitable for storage, retrieval, and analysis. The ability of software to direct the storage, retrieval, and analysis tasks is dependent not only on the efficiency of the software, but also on the structure of the spatial data. The key elements and formats required by spatial data handling systems must be identified and incorporated into spatial data structures. The requirements of and approaches being taken by the Geological Survey in performinng these takss reflect our need to manage and use large quantities of complex digital cartographic data.