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- W2123408082 abstract "We constrain azimuthal anisotropy in the West Antarctic upper mantle using shear wave splitting parameters obtained from teleseismic SKS, SKKS and PKS phases recorded at 37 broad-band seismometres deployed by the POLENET/ANET project. We use an eigenvalue technique to linearize the rotated and shifted shear wave horizontal particle motions and determine the fast direction and delay time for each arrival. High-quality measurements are stacked to determine the best fitting splitting parameters for each station. Overall, fast anisotropic directions are oriented at large angles to the direction of Antarctic absolute plate motion in both hotspot and no-net-rotation frameworks, showing that the anisotropy does not result from shear due to plate motion over the mantle. Further, the West Antarctic directions are substantially different from those of East Antarctica, indicating that anisotropy across the continent reflects multiple mantle regimes. We suggest that the observed anisotropy along the central Transantarctic Mountains (TAM) and adjacent West Antarctic Rift System (WARS), one of the largest zones of extended continental crust on Earth, results from asthenospheric mantle strain associated with the final pulse of western WARS extension in the late Miocene. Strong and consistent anisotropy throughout the WARS indicate fast axes subparallel to the inferred extension direction, a result unlike reports from the East African rift system and rifts within the Basin and Range, which show much greater variation. We contend that ductile shearing rather than magmatic intrusion may have been the controlling mechanism for accumulation and retention of such coherent, widespread anisotropic fabric. Splitting beneath the Marie Byrd Land Dome (MBL) is weaker than that observed elsewhere within the WARS, but shows a consistent fast direction, possibly representative of anisotropy that has been ‘frozen-in’ to remnant thicker lithosphere. Fast directions observed inland from the Amundsen Sea appear to be radial to the dome and may indicate radial horizontal mantle flow associated with an MBL plume head and low upper mantle velocities in this region, or alternatively to lithospheric features associated with the complex Cenozoic tectonics at the far-eastern end of the WARS." @default.
- W2123408082 created "2016-06-24" @default.
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- W2123408082 date "2014-05-21" @default.
- W2123408082 modified "2023-10-18" @default.
- W2123408082 title "Upper mantle seismic anisotropy beneath the West Antarctic Rift System and surrounding region from shear wave splitting analysis" @default.
- W2123408082 cites W1519554290 @default.
- W2123408082 cites W1528574941 @default.
- W2123408082 cites W1594745218 @default.
- W2123408082 cites W1714661189 @default.
- W2123408082 cites W1963619828 @default.
- W2123408082 cites W1968094597 @default.
- W2123408082 cites W1972081641 @default.
- W2123408082 cites W1973665559 @default.
- W2123408082 cites W1980935973 @default.
- W2123408082 cites W1984595274 @default.
- W2123408082 cites W1985183436 @default.
- W2123408082 cites W1989342053 @default.
- W2123408082 cites W1990365623 @default.
- W2123408082 cites W1993929875 @default.
- W2123408082 cites W1995072754 @default.
- W2123408082 cites W1995988653 @default.
- W2123408082 cites W1996697775 @default.
- W2123408082 cites W2000186159 @default.
- W2123408082 cites W2000954496 @default.
- W2123408082 cites W2006918718 @default.
- W2123408082 cites W2011970992 @default.
- W2123408082 cites W2013360601 @default.
- W2123408082 cites W2014206039 @default.
- W2123408082 cites W2015307066 @default.
- W2123408082 cites W2022965235 @default.
- W2123408082 cites W2031217923 @default.
- W2123408082 cites W2035501773 @default.
- W2123408082 cites W2037208969 @default.
- W2123408082 cites W2037791669 @default.
- W2123408082 cites W2038267743 @default.
- W2123408082 cites W2039576656 @default.
- W2123408082 cites W2040123418 @default.
- W2123408082 cites W2040234272 @default.
- W2123408082 cites W2040598280 @default.
- W2123408082 cites W2043804156 @default.
- W2123408082 cites W2044612552 @default.
- W2123408082 cites W2047510059 @default.
- W2123408082 cites W2049071401 @default.
- W2123408082 cites W2050608427 @default.
- W2123408082 cites W2053467403 @default.
- W2123408082 cites W2055025778 @default.
- W2123408082 cites W2057465591 @default.
- W2123408082 cites W2058359525 @default.
- W2123408082 cites W2059472212 @default.
- W2123408082 cites W2059674445 @default.
- W2123408082 cites W2059982963 @default.
- W2123408082 cites W2062018184 @default.
- W2123408082 cites W2063937978 @default.
- W2123408082 cites W2067368961 @default.
- W2123408082 cites W2067396291 @default.
- W2123408082 cites W2068615100 @default.
- W2123408082 cites W2069302116 @default.
- W2123408082 cites W2071872408 @default.
- W2123408082 cites W2074175234 @default.
- W2123408082 cites W2075579994 @default.
- W2123408082 cites W2081325424 @default.
- W2123408082 cites W2082973204 @default.
- W2123408082 cites W2084990552 @default.
- W2123408082 cites W2085555806 @default.
- W2123408082 cites W2088528402 @default.
- W2123408082 cites W2090407947 @default.
- W2123408082 cites W2091746476 @default.
- W2123408082 cites W2096361403 @default.
- W2123408082 cites W2097800673 @default.
- W2123408082 cites W2102213705 @default.
- W2123408082 cites W2102627932 @default.
- W2123408082 cites W2104133227 @default.
- W2123408082 cites W2106332207 @default.
- W2123408082 cites W2107469404 @default.
- W2123408082 cites W2109151783 @default.
- W2123408082 cites W2112009358 @default.
- W2123408082 cites W2113790549 @default.
- W2123408082 cites W2116471562 @default.
- W2123408082 cites W2116615769 @default.
- W2123408082 cites W2117580125 @default.
- W2123408082 cites W2125139449 @default.
- W2123408082 cites W2134635020 @default.
- W2123408082 cites W2136091602 @default.
- W2123408082 cites W2137508954 @default.
- W2123408082 cites W2138180105 @default.
- W2123408082 cites W2138793201 @default.
- W2123408082 cites W2139217443 @default.
- W2123408082 cites W2141316582 @default.