Tomographic evidence for localized lithospheric shear along the Altyn Tagh fault

Science

Volumn 282, Issue 5386, 1998, Pages 74-76

  Wittlinger, Gérard ^a   Tapponnier, Paul ^b   Poupinet, Georges ^a   Mei, Jiang ^c   Danian, Shi ^c   Herquel, Georges ^a   Masson, Frédéric ^a  

^a CNRS   (France)

^b INSTITUT DE PHYSIQUE DU GLOBE DE PARIS   (France)

^c INSTITUTE OF MINERAL RESOURCES   (China)

Author keywords

[No Author keywords available]

Indexed keywords

LITHOSPHERE; SEISMIC VELOCITY; SHEAR; STRIKE-SLIP FAULT;

ARTICLE; ASIA; CHINA; EARTHQUAKE; INDIAN OCEAN; PRIORITY JOURNAL; SEDIMENT; TOMOGRAPHY; TOPOGRAPHY; VELOCITY;

CHINA;

EID: 0032476025     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.282.5386.74     Document Type: Article

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18. The ACH technique (17) involves partition of the target volume into layers (7) subdivided into blocks. Artifacts due to inappropriate initial model parametrization are minimized by averaging the results of five different inversions performed by shifting blocks horizontally by one half-block size in four orthogonal directions (16). The tomographic image is corrected for near-surface effects and sediment thickness by introducing a 10-km-thick surface layer with a cone below each station (16), for which a delay and velocity perturbation is computed. Because the cones do not overlap, the velocity perturbations are not smeared.
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