Geographic Information Systems (GIS) applications in the Active Tectonics Research Group

DIGITAL MAP AND DATABASE PROJECTS

Digital Geologic Map Compilation The active tectonics group at ASU has compiled a number of geologic field maps related to research on the San Andreas Fault zone near Parkfield, CA into digital format through the use of ArcMap GIS software. Field maps were first rectified into the UTM Nad 1983 coordinate system. Next, all contacts were digitized to polyline feature classes, and finally, polygons were created that were bound by the contact polylines. This large dataset was managed through the use of various attribute tables associated with each feature class. REFERENCE: Thayer, M.R., Arrowsmith, J R., Young, J. J., Fayon, A., Rymer, M.J., 2004, Geologic structure of Middle Mountain within the San Andreas Fault zone near Parkfield, California, Eos Trans. AGU, 85 (47), Fall Meet. Suppl., Abstract T13A-1335, 2004. For more information on this project please visit our Geology and Geomorphology of the San Andreas Fault near Parkfield, CA page.

September 27, 2004 Parkfield Earthquake High-Resolution Fracture Mapping This M6 earthquake occured soon after the completion of a paleoseismic trenching project completed by our group on the SAF near Parkfield, CA. A total station was used to survey trench-site topography, trench outlines, and fractures associated with the 2004 Parkfield earthquake. Benchmark rotation was used to place the total station data into the appropriate UTM position for import to our Parkfield GIS. The figure at left was created in ArcScene to show a 3d perspective view of the trenchsite and the cracking data collected with the totalstation. Here the sag pond and pressure ridge are seen clearly. The black trench-footprints also contain the surveyed fault zones and their orientations (white) from our paleoseismic investigation. From the fault zone relationship to the 2004 EQ cracking (yellow) it is clear that only certain fault zones in each trench were activated in 2004. For more information on this project please visit our Geology and Geomorphology of the San Andreas Fault near Parkfield, CA page.

Digital Database of Faulting Accompanying the 1966 Parkfield, California, Earthquake This digital map database is prepared from a previously published map by Lienkaemper and Brown (1985). The fault database delineates tectonic ground rupture associated with the 1966 Parkfield, California earthquake and observation localities along the surface rupture where geologic data were gathered. The goal of this product is to provide earthquake scientists working along the San Andreas fault near Parkfield with a digital version of the Lienkaemper and Brown (1985) map that may be used for field work, input to geophysical models, and for comparison to the next Parkfield earthquake. REFERENCE Crosby, C.J., 2004, Digital database of faulting accompanying the 1966 Parkfield, California Earthquake, U.S. Geological Survey Open File Report, 2004-1437. For more information on this project please visit our Geology and Geomorphology of the San Andreas Fault near Parkfield, CA page.

Integration of GIS and InSAR Data Interferometric Synthetic Aperture Radar (InSAR) images (like the one at left) are being used to characterize ground subsidence within the western portion of the Phoenix Valley. The image corresponds to a period from 1992 to 2000 and a displacement scale of ~ 5 cm for each full color. The images are made up of an array of XYZ data, thus when two images are subtracted, the difference in values corresponds to the amount of displacement that has occurred since the previous acquisition. Using Spatial Analyst within ArcGIS, the XYZ data for each ~15 month time frame was rasterized using inverse distance weighted interpolation methods. Deformation along the profile line (the NW-SE trending black line in the image) was extracted and exported for display. The resulting graph can then be used to help understand temporal and spatial variation in subsidence. The InSAR images were produced by the Vexcel Corporation for ADWR through a NASA grant. For more information on this project please visit the Environmental Geophysics and recharge studies page.

INTERACTIVE DATA PORTALS AND SERVLET-BASED TOOLS

Interactive Data Portal and online ASTER Image Processing As part of the Geoinformatics Initiative, Arizona State University and the University of Texas at El Paso have teamed up to construct an integrated data system focusing on the Transition Zone between the Colorado Plateau and the Basin and Range Province, located primarily in Arizona and New Mexico. The region is of fundamental significance if we are to understand the geologic evolution of Southwestern North America and to address practical problems such as the effects of urbanization and dwindling water resources. Thus, this region is an excellent place to construct a prototype data system for Earth Science investigations. This project is funded by the National Science Foundation Information Technology Research (ITR) program and builds on our existing projects supported by NASA in particular. GIS capabilites developed for this project include an ArcIMS-based interactive data portal and servlet-based ASTER satellite image processing tool. For more information on this project please visit: SWGEONET Geoinformatics @ ASU

Servlet-Based Visualization Toolset The Parkfield Unified Visualization Project (PUVP) is a geospatial data repository, with the added benefits of easy, WWW-driven access and an in-house Virtual Reality Markup Language (VRML) generator to allow visualization of multiple data sets over the web. The data are stored georeferenced, and queried using GRASS Open Source GIS. The user queries this data via a Java web form which runs a series of Perl scripts to extract these data from the GRASS database in either GRASS or ARC/ESRI format. The scripts also convert this data into VRML directives that can be displayed using any web browser with a VRML plugin, or on a GeoWall. This project is completely open source, and we hope will be built up by contributions of both data and code by the user community. REFERENCE: Wurman, G., Arrowsmith, J R., Conner, J.S., 2004, Parkfield Unified Visualization Project: A Repository of Geospatial Data and Portable Toolset for its Visualization, Eos Trans. AGU, 85 (47), Fall Meet. Suppl., Abstract T13A-1338, 2004. For more information on this project please visit: The PUVP homepage. PUVP visualization tool The Geology and Geomorphology of the San Andreas Fault near Parkfield, CA page

Servlet-Based LiDAR / ALSM Data Processing Using GRASS Open Source GIS and java servlet architecture, we have built a web-based tool (the "lservlet") for the interpolation and analysis of LiDAR / ALSM high-resolution topographic data. The tool offers user upload of ascii based LiDAR return data, interpolation to grid by a number of user defined methods, and download of Digital Elevation Models (DEM) and related derived products. The lservlet runs on our GEON compute node and it's development represents one of our efforts as part of this National Science Foundation Information Technology Research (ITR) program funded grants. REFERENCE: Crosby, C.J., Arrowsmith, J.R., LiDAR Data Distribution, Interpolation and Analysis on the GEON Grid - A Conceptual Framework, Geological Society of America Annual meeting, Paper No. 60-6, 2004. For more information on this project please visit: LiDAR / ALSM related research in the Active Tectonics Group The GRASS-based LiDAR Processing Project Geoinformatics @ ASU

FIELD-BASED GEOGRAPHIC INFORMATION SYSTEMS

Digital Geologic Mapping using Tablet Computers Our research group is pursuing the use of tablet computers to digitally map in the field. Tablet computers are portable personal computers that are a powerful new tool for field scientists because they can improve field visualizations (2D & 3D), data acquisition and how we share and communicate data. These compact computers have been built to withstand harsh field conditions and can be carried in a removable harness. The computers typically run a standard operating system which allows the use of full-feature GIS software (such as ArcGIS). Application of GIS in the field makes it possible to integrate field observations with digital aerial photography, topographic maps, geologic maps and remotely sensed data. In addition, directly entering observations into the GIS while in the field removes the need to invest time digitizing data at a later date. Navigation of the computer is controlled by a sensor tipped pen which provides a way to take digital notes and drawings. Internal GPS tracks and displays your location so that observations and notes can be geolocated. For more information see the GeoPad Website: http://geopad.org/

Page maintained by: Chris Crosby
Last updated: June 1, 2005