HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) References Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Searcy, C. K. Articles by Zandt, G. Search for Related Content GeoRef GeoRef Citation

Velocity structure beneath College Station Alaska from receiver functions

Geophysical Institute University of Alaska Fairbanks, 903 Koyukuk Dr., Fairbanks, Alaska 99775-7320
Institute of Geophysics and Planetary Physics Lawrence Livermore National Laboratory, Livermore, California 94550

Abstract

Time-domain inversions of radial receiver functions and forward modeling of radial and tangential receiver functions were used to determine the velocity structure beneath DWWSSN station COL (Fairbanks, Alaska). Intermediate-period waveforms from 57 events recorded between February 1982 and November 1985 were used in the final analysis.

Receiver functions from similar backazimuths and distances are very uniform and were stacked to increase the signal-to-noise ratio. At some azimuths (particularly from the west), significant energy is observed in the tangential component, indicating the existence of heterogeneous structure. The calculated velocity profiles are complicated and contain several distinct features that are consistent between the different stacks. The most obvious features are two strong velocity increases or boundaries in the lower crust. The first of these velocity gradients is between 27 and 32 km, a depth that is often associated with the crust-mantle transition in this region. Forward modeling of the receiver function arrivals associated with this boundary indicates that it has a strike of 280° and a dip of at least 10° to the northeast. The velocity profiles and forward modeling also indicate a low-velocity layer between depths of about 15 and 28 km. This layer is consistent with TACT results that show a layer at approximately this depth, with high electrical conductivity and a lower-than-expected seismic velocity, interpreted to be Mesozoic flysch.

This article has been cited by other articles:

				B. H. Jacobsen and L. Svenningsen Enhanced Uniqueness and Linearity of Receiver Function Inversion Bulletin of the Seismological Society of America, August 1, 2008; 98(4): 1756 - 1767. [Abstract] [Full Text] [PDF]

				K. G. Lindquist, I. M. Tibuleac, and R. A. Hansen A Semiautomatic Calibration Method Applied to a Small-Aperture Alaskan Seismic Array Bulletin of the Seismological Society of America, February 1, 2007; 97(1B): 100 - 113. [Abstract] [Full Text] [PDF]

				T. M. Brocher, G. S. Fuis, W. J. Lutter, N. I. Christensen, and N. A. Ratchkovski Seismic Velocity Models for the Denali Fault Zone along the Richardson Highway, Alaska Bulletin of the Seismological Society of America, December 1, 2004; 94(6B): S85 - S106. [Abstract] [Full Text] [PDF]

				New Constraints on Tectonics of Interior Alaska: Earthquake Locations, Source Mechanisms, and Stress Regime Bulletin of the Seismological Society of America, April 1, 2002; 92(3): 998 - 1014.

				Receiver Functions from Multiple-Taper Spectral Correlation Estimates Bulletin of the Seismological Society of America, December 1, 2000; 90(6): 1507 - 1520.