Colorado Plateau/Rio Grande Rift Seismic Transect Experiment
(LA RISTRA)

RISTRA is a deep-imaging seismic experiment using naturally-occurring earthquake sources. The project is coordinated by between New Mexico Tech, New Mexico State, Los Alamos National Laboratory, Dine College, and the University of Texas at Austin.

RISTRA is funded by the National Science Foundation and the Institute of Geophysics and Planetary Physics at Los Alamos, and is supported by the IRIS Consortium Program for Array Seismic Studies of the Continental Lithosphere, PASSCAL.

The principal goal of RISTRA is to produce sharp images of the seismic structure of the lower crust and upper mantle beneath the Colorado Plateau, the Rio Grande Rift, and the southwestern Great Plains by recording and processing seismic signals generated by earthquakes occurring throughout the world. This imaging is shedding new light on past and present tectonic processes operating in western North America and in other regions of the world.

RISTRA 1 broadband seismometers were initially deployed in July of 1999, and the experiment was fully deployed by November 1999. Sites included lands managed by the Bureau of Land Management, the U.S. Forest Service, the U.S. Fish and Wildlife Service, the Navajo Nation, Laguna Pueblo, Isleta Pueblo, and the New Mexico State Land Office, and many cooperative private landowners. RISTRA 1 stations were removed from the field in May 2001. During RISTRA 1 over 400 teleseismic earthquakes with body wave magnitude >= 5.6 were recorded by the array.

In June of 2004, we began deployment of RISTRA 1.5 . This extension of RISTRA 1, funded by IGPP at Los Alamos National Laboratory (LANL), with equipment support provided by the IRIS PASSCAL Instrument Center, The University of Missouri, the University of Texas at Austin, and LANL, continued the experiment to the northwest, crossing the western boundary of the Colorado Plateau and extending into the Sevier Desert region of the Great Basin. Key science targets include enhanced imaging of the Colorado Plateau and its western margin. This data was recovered in summer of 2006 and is presently being analyzed.

More basic facts about RISTRA (information sheet distributed during the experiment). We also have a data summary report on line.


Topographic map (elevation in meters) with RISTRA 1 station locations. Stars represent the 57 stations, diamonds are nearby stations ANMO and ELPA, and triangles represent the stations of the CDROM experiment. Gray circles represent regional seismicity (M > 1.3; 1962-1998; Sanford et al., 1999).


Research Results

LA RISTRA research has been concentrated in four main research areas: receiver function analysis, shear wave splitting, surface waves, and upper mantle velocity tomography. Click on the pictures below to find out more about each topic.


Receiver Functions

Shear Wave Splitting

Surface Waves

Tomography

Presentations and Publications using LA RISTRA data:

Wilson, D., Sine, S., Grand, S., Aster, R., Ni, J., Colorado Plateau crust and upper mantle structure: Implications for uplift mechanisms, EOS Trans. AGU, 87(52), 2006.

Baldridge, W.S., Aster, R., Gao, W., Grand. S., Ni, J., Semken, S., West, M., Wilson, D., LA RISTRA (Colorado Plateau/Rio Grande Rift Seismic Transect Experiment) : A Geophysical Snapshot of Accumulated Collisional Processes on the Craton Margin, Partially Overprinted by Cenozoic Rifting, NM Geological Society Annual Spring Meeting, 21 April, 2006.

Wilson, D., and the RISTRA Research Group, Preliminary Images of Colorado Plateau Crust and Upper Mantle Seismic Structure, IRIS Consortium 16th Annual Workshop, Stevenson, WA, 9-11 June, 2005.

Wilson, D., Aster, R., West, M., Ni, J., Grand, S., Gao, W., Baldridge, W.S., Semken, S., Lithospheric Structure of the Rio Grande Rift, Nature, 433, doi:10.1038/nature03297, 2005. Associated article in the Albuquerque Journal.

Wilson, D., Aster, R., Seismic imaging of the crust and uppermantle using regularized joint receiver functions,frequency.wave number filtering, and multimode Kirchhoff migration, J. Geophys. Res., 110, B05305, doi:10.1029/2004JB003430, 2005.

Wilson, D., Aster, R., Ni, J., Grand, S., West, M., Gao, W., Baldridge, W.S., Semken, S., Imaging the seismic structure of the crust and upper mantle beneath the Great Plains, Rio Grande Rift, and Colorado Plateau using receiver functions, J. Geophys. Res., 110, B05306, doi:10.1029/2004JB003492, 2005.

Wilson, D. Aster, R., Receiver Function Seismic imaging of the Crust and Upper Mantle Using Frequency-Wavenumber Filtering and Regularized Multimode Kirchhoff Migration, Fall, 2004 AGU meeting, EOS trans. AGU, 85(47), 2004.

West, M., Gao, W., Grand, S., A simple approach to the joint inversion of seismic body and surface waves applied to the southwest U.S., Geop. Res. Lett., 31, L15615, doi:10.1029/2004GL020373, 2004. (PDF Version).

Gao, W., S. Grand, W.S. Baldridge, D. Wilson, M. West, J. Ni, and R. Aster, Upper mantle convection beneath the central Rio Grande rift imaged by P and S wave tomography, J. Geophys. Res., 109, B03305, doi:10.1029/2003JB002743, 2004. (PDF Version).

West, M., J. Ni, W.S. Baldridge, D. Wilson, R. Aster, W. Gao, and S. Grand, Crust and upper mantle shear wave structure of the southwest United States: Implications for rifting and support for high elevation, J. Geophys. Res., 109, B03309, doi:10.1029/2003JB002575, 2004. (PDF Version).

Gao, W., Grand S., Baldridge W.S., Wilson D., West, M., Ni, J., Aster, R., Convection beneath the Rio Grande Rift and surrounding regions deduced from tomographic seismic images, Fall, 2003 AGU meeting, EOS trans. AGU, 84(46), 2003.

Wilson et al., Imaging crust and upper mantle seismic structure in the southwestern United States using teleseismic receiver functions, The Leading Edge, v.22, n.3, p.232-237, 2003. Preprints: [ version from TLE ] [ printable version ]

Gok, R., J.F. Ni, E. Sandvol, D. Wilson, W.S. Baldridge, R. Aster, M. West, S. Grand, W. Gao, F. Tilmann, and S. Semken, Shear wave splitting and mantle flow beneath LA RISTRA, Geophys. Res. Lett., 30, n. 12, 1614, doi:10.1029/2002GL016616, 2003. (PDF Version).

Gao et al., Mantle Dynamics Beneath the Rio Grande Rift and Colorado Plateau, Fall Meet. Suppl., Abstract S61A-1115, 2002. (PDF Version).

Wilson et al., Crust and Upper Mantle Structure in the Southwestern United States Using Receiver Functions, SSA 2002 meeting, (HTML version of the poster).

Wilson et al., Seismic Structure of the Lithosphere in the Southwestern United States Using Receiver Functions, Eos Trans. AGU, 83(47), Fall Meet. Suppl., Abstract S61A-1113, 2002

Wilson et al., Broadband Seismic Background Noise at Temporary Seismic Stations Observed on a Regional Scale in the Southwestern United States, Bull. Seismol. Soc. Amer., v.92, n.8, p.3335-3341, 2002. ( PDF version ).

Ni et al., Shear Wave Splitting and Mantle Flow Beneath the Ristra Array, Fall Meet. Suppl., Abstract S61A-1114, 2002, (Adobe Illustrator version of the poster).

West et al., Structure of the Uppermost Mantle Beneath the RISTRA Array From Surface Waves, AGU 2002 fall meeting Fall Meet. Suppl., Abstract S61A-1116, 2002

Matzel et al., The seismic structure of the upper mantle beneath the northwestern United States, Eos Trans. AGU, 82(47), Fall Meet. Suppl., Abstract S21F-08, 2001

Gao et al., Mantle Seismic Structure beneath the Colorado Plateau, Rio Grande Rift and Great Plains from Seismic Tomography. Eos Trans. AGU, 82(47), Fall Meet. Suppl., Abstract S21F-07, 2001

Wilson et al., Crust and Upper Mantle Structure of the Colorado Plateau - Rio Grande Rift - Great Plains Transect Using Teleseismic Receiver Functions, Eos Trans. AGU, 82(47), Fall Meet. Suppl., Abstract S21F-09, 2001

Rosca et al., A crustal low velocity zone under the Colorado Plateau; Rio Grande Rift transition zone, Eos Trans. AGU, 81 (48), Fall Meet. Suppl., Abstract T22B-07, 2000

RISTRA collaborators

Rick Aster aster@ees.nmt.edu and Jonathan MacCarthy jkmacc@nmt.edu
New Mexico Institute of Mining and Technology, Socorro, NM, 87801
The New Mexico Tech Geophysics homepage.

David Wilson dwilson@usgs.gov
USGS Hawaiian Volcano Observatory
PO Box 51, 1 Crater Rim Road
Hawaii National Park, HI 96718

Jim Ni jni@nmsu.edu,
Mike West west@nmsu.edu,
New Mexico State University, Department of Physics (MSC 3D), Las Cruces, NM 88003
The New Mexico State Geophysics homepage.

Steve Grand steveg@speer.geo.utexas.edu,
Wei Gao gao@speer.geo.utexas.edu,
University of Texas, Austin, Department of Geological Sciences, Austin, TX 78712
The UT Austin Geophysics homepage.

Scott Baldridge sbaldridge@lanl.gov,
Los Alamos National Laboratory, EES-1, Los Alamos, NM 87545
The Los Alamos National Laboratory Earth and Environmental Sciences homepage.

Steve Semken semken@asu.edu,
Department of Geological Sciences, Arizona State University, Tempe, AZ
(formerly of Diné College, Division of Natural Sciences, Shiprock, NM)
The ASU Geology homepage.

Eric Sandvol sandvole@missouri.edu,
Department of Geological Sciences, University of Missouri, Columbia, MO 65211
The U of Missouri Geophysics homepage.

This page last updated August 21, 2007, for questions or comments about this page, contact Rick Aster (see above).