The Broadband Experiment Across the Alaska Range:  BEAAR


This 36-station broadband experiment sampled the crust, mantle, and subducting plate beneath central Alaska between Anchorage and Fairbanks (regional map).  Here are some 1999 field pictures and some 2000 pictures.  It samples the roots of the region around Mt. McKinley, the subducting plate beneath Alaska as it descends from 60 to >150 km depth, and the intervening mantle wedge.  The deployment lasted from June 1999 to August 2001.


This figure shows the deployment: (map).  Stations in red operated the entire duration of the experiment, May 1999 – August 2001.  Other stations were installed May-June 2000, and operated for 5 to 15 months.  The inset shows a 6-element phased array on Reindeer Mountain.


All data are available through the IRIS DMC.

Major Collaborators


Boston University   

Geophysical Institute, University of Alaska Fairbanks

Funding provided by the U.S. National Science Foundation,  Geophysics program

Instruments made available by the IRIS-PASSCAL Instrument Center


Boston University

PI:  Geoff Abers

Graduate Students:  Josh Stachnik, Aaron Ferris, Gio Rossi

Undergraduates:  Sara Pozgay, Dan Hoak, Brad Scott

University of Alaska Fairbanks

PI:  Doug Christensen, Roger Hansen

Graduate Students:  Liz Veenstra (Meyers), Duncan Marriot

Undergraduates: Maggie Benoit, Maggie Pollock, Addie Holland, Kate Beebe, Amie Lucier, Jacob Cooper, Toni McKnight

Major Publications

Papers.  BU and UAF students underlined.  Contact Abers or first author for preprints/reprints if not linked below.

Ferris, A., G.A. Abers, D.H. Christensen and E. Veenstra, High resolution image of the subducted Pacific (?) plate beneath central Alaska, 50-150 km depth, Earth Planet. Sci. Lett., 214, 575-588, 2003. (PDF)

Ekström, G., M. Nettles and G.A. Abers, Glacial Earthquakes, Science, 302, 622-624, 2003.

Stachnik, J.C., Abers, G.A., and D. Christensen, Seismic attenuation and mantle wedge temperatures in the Alaska subduction zone, J. Geophys. Res., 109, B10304, doi:10.1029/2004JB003018, 2004. (PDF)

Paul, A., M. Campillo, L. Margerin, E. Larose, and A. Derode (2005), Empirical synthesis of time-asymmetrical Green functions from the correlation of coda waves, J. Geophys. Res., 110, B08302, doi:08310.01029/02004JB003521.

Abers, G.A., P.E. van Keken, E.A. Kneller, A. Ferris, and J.C. Stachnik, The thermal structure of subduction zones constrained by seismic imaging: Implications for slab dehydration and wedge flow, Earth Planet. Sci. Lett., 241, 387-397, 2006. (PDF)

Rossi, G., G.A. Abers, S. Rondenay and D.H. Christensen, Unusual mantle Poisson’s ratio, subduction and crustal structure in Central Alaska, J. Geophys. Res., 111, B09311, doi:10.1029/2005JB003956, 2006. (PDF)

Veenstra, E., D. Christensen, G. A. Abers and A. Ferris, Crustal thickness variation in south central Alaska:  Results from the Broadband Experiment Across the Alaska Range, Geology, 34, 781-784, 2006. (PDF)

Eberhart-Phillips, D., D.H. Christensen, T.M. Brocher, R. Hansen, N.A. Ratchkovski, and G. Abers, Imaging the transition from Aleutian subduction to Yakutat collision in central Alaska, with local earthquakes and active source data, J. Geophys. Res., 111, B11303, doi:10.1029/2005JB004240, 2006.




Stachnik, J.C.,  Seismic Attenuation in Central Alaska, MA Thesis, Boston Univ., 122 pp., 2002.

Rossi, G., Measuring the Mantle Wedge Poisson’s Ratio and Slab Depth: Central Alaska, MA Thesis, Boston Univ., 121 pp., 2004.  (Text – PDF, 450K)  (Figures – MSWord – 13Mb)

Selected abstracts on material not included above

Rondenay, S., G.A. Abers and A. Ferris, A new, high-resolution seismic profile of the central-Alaskan subduction zone,  EOS Trans. AGU, 85(17), Jt. Assem. Suppl., Abstract U54A-05, 2004.

Abers, G.A. and G. Hirth, Seismic attenuation constraints on temperature and water content of the mantle wedge, EOS Trans. AGU, 85(17), Jt. Assem. Suppl., Abstract U54A-04, 2004.

Christensen, D.H., G.A. Abers, and T. McNight, Mantle Anisotropy Beneath the Alaska Range Inferred From S-wave Splitting Observations:  Results From BEAAR, EOS Trans. AGU, 84 (46), Fall Meet. Suppl., Abstract S31C-0782, 2003.

Campillo, M., E. Larose, L. Margerin, A. Paul,  B. van Tiggelen, A. Derode, and G. Abers, Empirical Synthesis of Green functions from the correlation of diffuse waves, EOS Trans. AGU, 84 (46), Fall Meet. Suppl., Abstr. S11E-0339, 2003.

Stachnik, J., G.A. Abers and D. Christensen, The Broadband Experiment Across the Alaska Range (BEAAR) Project: A Preliminary Report of Local Earthquakes From an IRIS Intern Perspective, EOS Trans. AGU, 80, Fall 1999 Meeting Suppl., F725, 1999.


updated May 2006