Active tectonics, tectonic geomorphology, and fault system dynamics: how geoinformatics can help J Ram´ on Arrowsmith Department of Geological Sciences Arizona State University Tempe, AZ 85287-1404 USA ramon.arrowsmith@asu.edu October 17, 2003 Abstract Active tectonics, tectonic geomorphology, and fault systems dynamics are subdomains of plate tectonics investigations that relate to continental crustal deformation over late Quaternary to annual timescales. They are interdisciplinary endeavors requiring the joint analysis of diverse datasets and model results. Data gathering and scientific analysis to be driven by the recently initiated Earthscope initiative motivates a discussion of how to apply the tools of geoinformatics to enhance these efforts. I use 3 information integration scenarios for earthquake geology site context, basic digital elevation model (DEM) analysis, and tectonic geomorphology to show the the kinds of analyses, integrations, and visualizations that are commonly employed. Earthquake geology site context for Hog Lake along the San Jacinto fault in southern California ranges in scale from the San Andreas Transform boundary (hundreds of km) to 10s of centimeters of topographic and balloon photographic resolution. Simple manipulations of a 30-m DEM for the Carrizo Plain, California illustrate the basic record of deformation and surface processes recorded in the topography. Tectonic geomorphologic investigations at Wheeler Ridge in south-central California include visualization of imagery and geology with topography, arithmetic and boolean raster calculations to produce a map of local relief, and the integration of mechanical fault model calculations for surface uplift. Necessary datasets include seismicity, crustal motion, stress measurements, topography, remotely sensed imagery, Quaternary faults, locations and magnitudes of late Cenozoic subsidence and uplift, and geological maps emphasizing Quaternary geology. Necessary geoinformatics tools include visualization and cartography, file format and database translation/filters, geostatistics, comprehensive data query capability, data capture, augmentation of field reality, interpretive (physics-based) models for deformation and landscape development. Potential collaborations will improve earth scientists’ ability to create knowledge, while providing useful domain challenges for information technologists. 1