A RELATIONAL DATABASE SCHEMA FOR MANAGING GEOCHEMICAL AND VISUAL DATA: THE ALEUTIAN ARC DATA SYSTEM (AADS)

Recently, applications have been created to store, manage and deliver online the extensive geochemical data generated by modern petrologic studies. Foremost among these are RIDGE PetDB and GEOROC, which use similar database schema and implement comparable functionality. Both handle a variety of sample types, multiple analyses of single samples, customized queries and varied geochemical data. Samples are described by extensive metadata. Independently, we have developed a different relational database-Web interface system (Aleutian Arc Data System – AADS [http://www.gg.uwyo.edu/aleutians/]) that provides similar geochemical functionality but incorporates unique capabilities well suited for land-based petrologic studies. In such studies, samples are described in detailed spatial, temporal and geologic frameworks that logically define associations of samples. Thus spatially, a sample comes from a particular volcanic island, is part of a volcanic complex on that island, was erupted from a single volcano and collected from a particular outcrop. Other associations might be based on formation, age, map unit, etc. Using such associations and recursive relationships, we created a hierarchical structure in which individual samples are assigned different and possibly overlapping associations. Thus, an educator or researcher can request only samples from Adak Island or Sugarloaf Volcano. At the same time, these associations can be filtered via user-defined criteria, e.g. MgO content. Land-based studies also produce abundant visual imagery, e.g. outcrop, sample and field photos or videos. Because such information is useful for setting the geologic content of geochemical data, our database schema handles a variety of visual information including photos, videos, panoramas and DEM-generated 3-D models. As such digital formats become easier to produce, databases using the AADS schema will provide site bound investigators with a solid understanding of local topography and geology, especially for such isolated localities as the Aleutians. Our database also stores topographic, sample and geologic maps. Because the AADS database schema uses local temporal, geologic and/or spatial criteria to create its hierarchical information structure, it can be readily adapted to other geologic provinces or bodies.