COSEISMIC SLIP IN THE 1964 PRINCE-WILLIAM-SOUND EARTHQUAKE - A NEW GEODETIC INVERSION

被引：69

作者：

HOLDAHL, SR

SAUBER, J

机构：

[1] National Geodetic Survey, C and GS, National Ocean Service, NOAA, Silver Spring, 20910-3282, MD

[2] Geodynamics Branch, Lab. for Terrestrial Physics, NASA/Goddard Space Flight Center, Greenbelt, 20771, MD

来源：

PURE AND APPLIED GEOPHYSICS | 1994年 / 142卷 / 01期

关键词：

ALASKA EARTHQUAKE; PRINCE-WILLIAM-SOUND; MODELING; KODIAK; COSEISMIC SLIP; GEODETIC; KENAI PENINSULA;

D O I：

10.1007/BF00875968

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

The 1964 Prince William Sound earthquake (March 28, 1964; M(w) = 9.2) caused crustal deformation over an area of approximately 140,000 km2 in south central Alaska. In this study geodetic and geologic measurements of this surface deformation were inverted for the slip distribution on the 1964 rupture surface. Previous seismologic, geologic, and geodetic studies of this region were used to constrain the geometry of the fault surface. In the Kodiak Island region, 28 rectangular planes (50 by 50 km each) oriented approximately 218-degrees-N, with a dip varying from 8-degrees nearest the Aleutian trench to 9-degrees below Kodiak Island, define the rupture surface. In the Prince William Sound region 39 planes with variable dimensions (approximately 40 by 50 km near the trench, approximately 64 by 50 km inland) and orientation (218-degrees-N in the west and 270-degrees-N in the east) were used to approximate the complex faulting. Prior information was introduced to constrain offshore dip-slip values, the strike-slip component, and slip variation between adjacent planes. Our results suggest a variable dip-slip component with local slip maximums occurring near Montague Island (up to approximately 30 m), further to the east near Kayak Island (up to approximately 14 m), and trenchward of the northeast segment of Kodiak Island (up to approximately 17 m). A single fault plane dipping 30-degrees-NW, corresponding to the Patton Bay fault, with a slip value of - 8 m modeled the localized but large uplift on Montague Island. The moment calculated on the basis of our geodetically derived slip model of 5.0 x 10(20) dyne cm is 30% less than the seismic moment of 7.5 x 10(29) dyne cm calculated from long-period surface waves (KANAMORI, 1970) but is close to the seismic moment of 5.9 x 10(29) dyne cm obtained by KIKUCHI and FUKAO (1987).

引用

页码：55 / 82

页数：28

共 28 条

[1]

Barrientos S.E., Ward S.N., The 1960 Chile Earthquake: Inversion for Slip Distribution from Surface Deformation, Geophys. J. Int., 103, pp. 589-598, (1990)

[2]

Brown L.D., Reilinger R.E., Holdahl S.R., Balazs E.I., Postseismic Crustal Uplift near Anchorage, Alaska, Journal of Geophysical Research, 82, pp. 3369-3378, (1977)

[3]

Christensen D., Beck S., The 1964 Prince William Sound Earthquake: Rupture Process and Plate Segementation, Pure and Appl. Geophys., 142, pp. 29-53, (1994)

[4]

Davies J.N., House L., Aleutian Subduction Zone Seismicity, Volcano-trench Separation, and their Relation to Great Thrust-type Earthquakes, J. Geophys. Res., 84, pp. 4583-4591, (1979)

[5]

DeMets C., Gordon R.G., Stein S., Argus D.F., A Revised Estimate of Pacific-North American Motion and Implications for Western North America Plate Boundary Zone Tectonics, Geophysical Research Letters, 14, pp. 911-914, (1987)

[6]

Harris R.A., Segall P., 1987: Detection of a Locked Zone at Depth on the Parkfield, California, Segment of the San Andreas Fault, J. Geophys. Res., 92, pp. 7945-7962, (1987)

[7]

Hastie L.M., Savage J.C., A Dislocation Model for the 1964 Alaska Earthquake, Bull. Seismol. Soc. Am., 60, 4, pp. 1389-1392, (1970)

[8]

Holdahl S.R., A Dynamic Vertical Reference System, Surveying and Land Information Systems, 52, 2, pp. 92-103, (1992)

[9]

Johnson J., Satake K., Slip Distribution of the 1964 Alaska Earthquake from Inversion of Tsunami Waveforms, EOS, Trans. Am. Geophys. Un., (1993)

[10]

Kanamori H., The Alaska Earthquake of 1964: Radiation of Long-period Surface Waves and Source Mechanism, Journal of Geophysical Research, 75, pp. 5011-5027, (1970)

← 1 2 3 →