Geophysics: The size and duration of the Sumatra-Andaman earthquake from far-field static offsets

Science

Volumn 308, Issue 5729, 2005, Pages 1769-1772

  Banerjee, P ^a   Pollitz, F F ^b   Burgmann R ^c  

^a WADIA INSTITUTE OF HIMALAYAN GEOLOGY   (India)

^b U S GEOLOGICAL SURVEY   (United States)

^c UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

EARTH (PLANET); EARTHQUAKE EFFECTS; GLOBAL POSITIONING SYSTEM; METHOD OF MOMENTS; RIGIDITY; SEISMIC PROSPECTING;

DEPTH-VARYING RIGIDITY; EPICENTER; STATIC OFFSETS;

EARTHQUAKES;

SUMATRA EARTHQUAKE 2004;

ARTICLE; ASTRONOMY; EARTHQUAKE; GEOLOGY; GEOMETRY; MODEL; PRIORITY JOURNAL;

ANDAMANS AND NICOBARS; ASIA; EASTERN HEMISPHERE; EURASIA; GREATER SUNDA ISLANDS; INDIA; MALAY ARCHIPELAGO; SOUTH ASIA; SOUTHEAST ASIA; SUMATRA; SUNDA ISLES; WORLD;

EID: 20544436962     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.1113746     Document Type: Article

References (16)

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4. The GPS data are from stations belonging to the IGS global network, the BAKOSURTANAL Indonesian network, the Sumatran GPS Array operated by the Tectonic Observatory at Caltech and the Indonesian Institute of Science (LIPI), and the Indian "National Program on GPS" Network of the Department of Science and Technology made available by the Survey of India GPS Data Centre.
5. We use daily solutions of global GPS stations processed and archived at the Scripps Orbital and Permanent Array Center (http://sopac.ucsd.edu). Eighteen IGS stations located >5000 km from the rupture are used in the ITRF-2000 reference frame realization. Our regional solution includes 25 stations, 9 of which are in common with the SOPAC solution (table 51).
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11. A spherical harmonic expansion from I=1 to I-1500 is used to represent the spherical displacement fields. The I=1 component is found to be very important for correctly synthesizing far-field displacements. For typical Sumatra slip models, the predicted displacement at the farthest (Korean) sites amounts to several mm and arises almost entirely from the I=1 component of the displacement field.
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13. A statistical F-test shows that the improvement in data fit with respect to Model M2 by including the additional two parameters of the Andaman segment is significant at 99.93% confidence (Model M1) or 99.76% confidence (Model M3).
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16. We thank C. P. Rajendran and R. Bilham for providing results before publication. GPS data processing was carried out under a Department of Science and Technology, Government of India-sponsored project (to P.B.).