CREATION OF A NORTH AMERICAN VOLCANIC AND PLUTONIC ROCK DATABASE (NAVDAT)

We are compiling NAVDAT, a database of geochemical and age information for Cenozoic igneous rocks in western North America. NAVDAT will allow unprecedented exploration of temporal and spatial patterns in igneous activity and will allow investigators to correlate these patterns with local and regional tectonic development and lithospheric structure. The database is web-accessible for downloads and queries (navdat.geo.ku.edu – soon to be part of the GEON Grid). Allied information, such as geologic and geophysical maps, crustal structure, etc., are or will also be available through a map interface. We are collaborating with other igneous database efforts, PetDB and GEOROC (petdb.ldeo.columbia.edu, georoc.mpch-mainz.gwdg.de), in order to develop compatible schema and to build consensus on an overall database structure. The three efforts have a common entry point at earthchem.org.

Work to date has included developing the data entry method and relational database structure, and archiving legacy data from published papers and theses. In addition, we have search routines working and plots of rock data as Harker diagrams, element-normalization diagrams, and on state map outlines. We are currently working at plotting data onto state and North American geologic maps. Samples are linked to GeoRef information for papers and theses.

Some preliminary results from NAVDAT are posted at navdat.geo.ku.edu, which shows a variety of graphical products produced from the data now in the database. Of particular interest is the animation of magmatism in the western U.S. over the past 65 m.y. In addition, the compilation shows the general evolution of igneous rocks to alkalic and bimodal compositions with time.