東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Shear wave splitting analysis beneat...

Cherie, Solomon Gerra.

Linked to FindBook

Google Book

Amazon

博客來

Shear wave splitting analysis beneath Tien Shan: Geodynamic implications of complex anisotropy.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Shear wave splitting analysis beneath Tien Shan: Geodynamic implications of complex anisotropy./
Author:	Cherie, Solomon Gerra.
Description:	125 p.
Notes:	Source: Dissertation Abstracts International, Volume: 76-11(E), Section: B.
Contained By:	Dissertation Abstracts International76-11B(E).
Subject:	Geophysics. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3711499
ISBN:	9781321877557

Shear wave splitting analysis beneath Tien Shan: Geodynamic implications of complex anisotropy.
Cherie, Solomon Gerra.

Shear wave splitting analysis beneath Tien Shan: Geodynamic implications of complex anisotropy. - 125 p.

Source: Dissertation Abstracts International, Volume: 76-11(E), Section: B.

Thesis (Ph.D.)--Missouri University of Science and Technology, 2015.

The Tien Shan is a tectonically complex intracontinental orogenic belt situated between the Tarim Basin and the Kazakh Shield. Previous shear wave splitting (SWS) studies conducted in the Tien Shan region resulted in a variety of anisotropy-forming hypotheses, including small-scale mantle convection, absolute-plate motion induced flow, and tectonic fabrics in the lithosphere. The vast majority of the previous SWS measurements were presented as station averages, which are only valid when the anisotropy structure can be approximated by a single layer of anisotropy. In this study, we measure the splitting parameters (fast orientations and splitting times) at 25 stations that recorded high-quality data from a wide back-azimuthal range for the purpose of identifying and characterizing complex anisotropy. Among the 25 stations, 15 of them show systematic azimuthal variations in the observed splitting parameters with a 90-degree periodicity, suggesting wide spread existence of double layered anisotropy in the study area. The fast orientations of the top layer range from 57 to 90° measured clockwise from the north, which are subparallel to the strike of the orogenic belt, and the splitting times are between 0.9-1.9 s. The corresponding values for the lower layer are -45 to -85° and 1.2-2.2 s, respectively. The remaining 10 stations demonstrate azimuthally invariant splitting parameters with strike-parallel fast orientations, and can be represented by a single layer of anisotropy with a horizontal axis of symmetry. We propose that the strike-parallel anisotropy is caused by lithospheric shortening, and anisotropy in the lower layer is associated with WNW-ward flow of asthenospheric material sandwiched between the subducting Tarim lithosphere and the thick Kazakh lithospheric root.

ISBN: 9781321877557Subjects--Topical Terms:

535228
Geophysics.

Shear wave splitting analysis beneath Tien Shan: Geodynamic implications of complex anisotropy.
LDR:02780nmm a2200301 4500 001 2077515
005 20161114130321.5
008 170521s2015 ||||||||||||||||| ||eng d
020 $a 9781321877557
035 $a (MiAaPQ)AAI3711499
035 $a AAI3711499
040 $a MiAaPQ $c MiAaPQ
100 1 $a Cherie, Solomon Gerra. $3 3193024
245 1 0 $a Shear wave splitting analysis beneath Tien Shan: Geodynamic implications of complex anisotropy.
300 $a 125 p.
500 $a Source: Dissertation Abstracts International, Volume: 76-11(E), Section: B.
500 $a Advisers: Stephen S. Gao; Kelly H. Liu.
502 $a Thesis (Ph.D.)--Missouri University of Science and Technology, 2015.
520 $a The Tien Shan is a tectonically complex intracontinental orogenic belt situated between the Tarim Basin and the Kazakh Shield. Previous shear wave splitting (SWS) studies conducted in the Tien Shan region resulted in a variety of anisotropy-forming hypotheses, including small-scale mantle convection, absolute-plate motion induced flow, and tectonic fabrics in the lithosphere. The vast majority of the previous SWS measurements were presented as station averages, which are only valid when the anisotropy structure can be approximated by a single layer of anisotropy. In this study, we measure the splitting parameters (fast orientations and splitting times) at 25 stations that recorded high-quality data from a wide back-azimuthal range for the purpose of identifying and characterizing complex anisotropy. Among the 25 stations, 15 of them show systematic azimuthal variations in the observed splitting parameters with a 90-degree periodicity, suggesting wide spread existence of double layered anisotropy in the study area. The fast orientations of the top layer range from 57 to 90° measured clockwise from the north, which are subparallel to the strike of the orogenic belt, and the splitting times are between 0.9-1.9 s. The corresponding values for the lower layer are -45 to -85° and 1.2-2.2 s, respectively. The remaining 10 stations demonstrate azimuthally invariant splitting parameters with strike-parallel fast orientations, and can be represented by a single layer of anisotropy with a horizontal axis of symmetry. We propose that the strike-parallel anisotropy is caused by lithospheric shortening, and anisotropy in the lower layer is associated with WNW-ward flow of asthenospheric material sandwiched between the subducting Tarim lithosphere and the thick Kazakh lithospheric root.
590 $a School code: 0587.
650 4 $a Geophysics. $3 535228
650 4 $a Geology. $3 516570
650 4 $a Geographic information science and geodesy. $3 2122917
650 4 $a Asian studies. $3 1571829
690 $a 0373
690 $a 0372
690 $a 0370
690 $a 0342
710 2 $a Missouri University of Science and Technology. $b Geology and Geophysics. $3 2098672
773 0 $t Dissertation Abstracts International $g 76-11B(E).
790 $a 0587
791 $a Ph.D.
792 $a 2015
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3711499