Propagation Path Effects for Rayleigh and Love Waves (Surface Wave Studies of the Bering Sea and Alaska Area)

• Main Authors: Herrin, Eugene, Goforth, Tom, Jin, Doo-Jung
• Other Authors: SOUTHERN METHODIST UNIV DALLAS TX DALLAS GEOPHYSICAL LAB
• Format: Text
• Language: English
• Published: 1979
• Subjects: Seismology; *SEISMIC WAVES; ALASKA; BERING SEA; MATCHED FILTERS; PHASE STUDIES; RAYLEIGH WAVES; SIGNAL PROCESSING; SIGNAL TO NOISE RATIO; SURFACE WAVES; TIME SERIES ANALYSIS; WAVE PROPAGATION; LOVE WAVES; Bering Sea; Bering Shelf; Alaska
• Online Access: http://www.dtic.mil/docs/citations/ADA148959; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA148959

The area of the Bering Sea and Alaska was studied in terms of shear- velocity, density and compressional-velocity structure by applying a generalized linear inversion method to fundamental-mode Rayleigh-wave group-velocity dispersion relationships in the period range from 10 to 100 sec. Group velocity dispersion relationships in the area were obtained by applying the phase-matched filtering technique to digitally recorded surface-wave data. A new exact analytical method for the computation of Rayleigh-wave phase-velocity partial derivatives with respect to Earth parameters was formulated. With the phase- velocity partial derivatives determined, the group velocity partial derivatives were computed by use of the fast and accurate method of Rodi, and were successfully incorporated into a generalized linear inversion method. In continental Alaska, the crustal thickness is 43 +or- km, and a low velocity zone extendes from a depth of about 113 km to about 213 km. In the Bering Shelf region, the depth to the Mohorovicic discountinuity is 28 +or- 4 km, and a low velocity zone ranges in depth from about 108 km to about 213 km. In the Aleutian Basin, the thickness of the crust is 18 +or- 4 km, and a low velocity zone extends from a depth of about 60 km to about 220 km.