Welcome to the Active Tectonics, Quantitative Structural Geology and Geomorphology website devoted to precariously balanced rocks.  This project, initiated in collaboration with Thomas C. Hanks of the US Geological Survey, will emphasize the study of the geomorphology of precariously balanced rocks and their situation in relatively low seismicity regions of Arizona and Southern California.

News & Updates

        November 2009
We wrote a code (in MATLAB) that estimates basic 2D geometric parameters of PBRs from unconstrained digital photographs.  The code, user manual, and sample PBR photographs are available here:  PBR fragility analysis

I'm looking for volunteers to test the code using the sample photographs.  For more information, contact David Haddad (contact information at bottom of this page).


        October 2009
We just completed preliminary processing of our newly acquired ALSM dataset for the Granite Dells!  Click here to see some of the products (0.25 m DEM):  ALSM Applications for Precarious Rock Research

The following is our 2009 SCEC progress report that summarizes our research efforts and results to date:  2009 SCEC Progress Report


        September 2009
We submitted three abstracts for poster and podium presentations at the 2009 AGU Meeting in San Francisco.  All material for this meeting can be accessed here:  2009 American Geophysical Union (AGU) Meeting materials

Our ALSM data for the Granite Dells precarious rock zone were collected!  Thanks to the NCALM pilots and crew for doing a great job and for showing us around their operations.  We expect to have the raw point clouds ready to be processed (and produce some sweet DEMs) before AGU.  Here are some photos of the plane and scanner setup: ALSM Applications to Precarious Rock Research


        August 2009
We submitted two abstracts for poster presentations at the 2009 SCEC Annual Meeting in Palm Springs.  We will present our latest results and methods in this project, including the collaborative effort between ASU, USGS Pasadena, and Caltech in documenting a precarious rock in Echo Cliffs, CA.  Materials for this are available here:  2009 Southern California Earthquake Center (SCEC) Meeting materials

We completed a terrestrial laser scanning expedition to scan some of our PBRs in the Granite Dells precarious rock zone.  We used a Riegl LPM 800i (aka LPM 321) that was borrowed from our colleagues at the Cybermapping  Lab of the University of Texas, Dallas.  We scanned a single PBR and PBR-covered hillslopes.  Here are some photos of the field setup (screen captures of the raw point clouds to come soon):  TLS Applications for Precarious Rock Research


        April 2009
We contributed an article to the April 2009 edition of the Arizona Geology newsletter (published by the Arizona Geological Survey) that describes research interests in the use of PBRs as natural seismometers.  Here is the link: 2009 Arizona Geology Newsletter article


        March 2009
Our proposal for a National Center for Airborne Laser Mapping (NCALM) seed grant to acquire ALSM data for one of our precarious rock zones was accepted!  We expect to collect the data by the end of this summer, and begin processing them soon after to generate high-resolution DEMs.  This will be the first application of ALSM technology to precariously balanced rocks research.  Here's the summary of the proposed work and a location map of the selected PBR zone:  2009 NCALM summary


        December 2008
We presented our research efforts at the 2008 AGU Fall Meeting, where we were awarded an Outstanding Student Paper Award - Hydrology Section for the poster.  All materials for this meeting are located in the following page:  2008 American Geophysical Union (AGU) Meeting materials


        September 2008
We presented a poster and two podium talks at the 2008 SCEC meeting.  All materials for this meeting can be accessed here:  2008 Southern California Earthquake Center (SCEC) Meeting materials


        July 2008
The following is our progress report that summarizes our PBR site-selection process:  2008 Progress Report


        April 2008
Here are some field photos from the Granite Dells area, near Prescott, AZ, taken on April 26, 2008 during a reconnaissance field trip with Thomas C. Hanks (USGS), Ramon Arrowsmith (ASU), David E. Haddad (ASU) and Matt Rossi (ASU).