東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

Upper mantle velocity structure bene...

Saint Louis University.

FindBook

Google Book

Amazon

博客來

Upper mantle velocity structure beneath the Tibetan Plateau from triplicated seismic P waveforms.

紀錄類型:	書目-語言資料,印刷品 : Monograph/item
正題名/作者:	Upper mantle velocity structure beneath the Tibetan Plateau from triplicated seismic P waveforms./
作者:	Chu, Risheng.
面頁冊數:	91 p.
附註:	Adviser: Lupei Zhu.
Contained By:	Dissertation Abstracts International69-07B.
標題:	Geophysics. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3324154
ISBN:	9780549759720

Upper mantle velocity structure beneath the Tibetan Plateau from triplicated seismic P waveforms.
Chu, Risheng.

Upper mantle velocity structure beneath the Tibetan Plateau from triplicated seismic P waveforms. - 91 p.

Adviser: Lupei Zhu.

Thesis (Ph.D.)--Saint Louis University, 2008.

In this study, P-wave waveforms in the upper-mantle distance range between 12° and 30° were analyzed to investigate upper-mantle P velocity structures beneath the Tibetan Plateau and surrounding areas. The waveform data were from 1,715 earthquakes of magnitudes larger than 5.0 between 1990 and 2005 that occurred within 30° from the center of the plateau. I first used teleseismic recordings of these events to verify their focal mechanisms from the Harvard CMT solutions and found 504 events with good focal mechanisms. I then developed a new method to estimate their source time functions and focal depths. For each event, I used the theoretical Green's functions to deconvolve with the teleseismic P-wave waveforms to obtain the source time function. The focal depth of the event was adjusted until the source-free P waveforms match the theoretical Green's functions. By using the method I obtained source time functions and depths for the 504 events. Comparison with the Harvard CMT solutions showed that Harvard CMT catalog systematically over-estimated both the source durations and depths.

ISBN: 9780549759720Subjects--Topical Terms:

535228
Geophysics.

Upper mantle velocity structure beneath the Tibetan Plateau from triplicated seismic P waveforms.
LDR:03186nam 2200277 a 45 001 854240
005 20100702
008 100702s2008 ||||||||||||||||| ||eng d
020 $a 9780549759720
035 $a (UMI)AAI3324154
035 $a AAI3324154
040 $a UMI $c UMI
100 1 $a Chu, Risheng. $3 1020559
245 1 0 $a Upper mantle velocity structure beneath the Tibetan Plateau from triplicated seismic P waveforms.
300 $a 91 p.
500 $a Adviser: Lupei Zhu.
500 $a Source: Dissertation Abstracts International, Volume: 69-07, Section: B, page: 4044.
502 $a Thesis (Ph.D.)--Saint Louis University, 2008.
520 $a In this study, P-wave waveforms in the upper-mantle distance range between 12° and 30° were analyzed to investigate upper-mantle P velocity structures beneath the Tibetan Plateau and surrounding areas. The waveform data were from 1,715 earthquakes of magnitudes larger than 5.0 between 1990 and 2005 that occurred within 30° from the center of the plateau. I first used teleseismic recordings of these events to verify their focal mechanisms from the Harvard CMT solutions and found 504 events with good focal mechanisms. I then developed a new method to estimate their source time functions and focal depths. For each event, I used the theoretical Green's functions to deconvolve with the teleseismic P-wave waveforms to obtain the source time function. The focal depth of the event was adjusted until the source-free P waveforms match the theoretical Green's functions. By using the method I obtained source time functions and depths for the 504 events. Comparison with the Harvard CMT solutions showed that Harvard CMT catalog systematically over-estimated both the source durations and depths.
520 $a I divided the studying area into 6 regions and modeled upper-mantle-distance P waveforms with turning points beneath each region separately. The results show that the upper-mantle P-wave velocity structures beneath India, the Himalayas and the Lhasa Terrane are similar and contain a high-velocity lid about 250 km thick. The Tarim Basin also lies above a high-velocity upper-mantle lid. The upper-mantle velocities over 200 km beneath the Qiangtang and Songpan-Ganzi Terranes are lower than those in the north and south, especially beneath the Songpan-Ganzi Terrane. The 410 discontinuity beneath these two terranes are elevated by 20 km. I also found high-velocity anomalies in the transition zone below 500 kin under the Lhasa and Qiangtang Terranes. The results suggest that the Tibetan Plateau was generated by the thrusting of the Indian mantle lithosphere under the southern part of Tibet. A portion of the thickened Asian lithosphere in northern Tibet was delaminated and is now sitting atop of the 410 discontinuity below it. The high-velocity anomalies in the transition zone beneath the Lhasa and Qiangtang Terranes are probably the remnants of subducted India mantle lithosphere.
590 $a School code: 0193.
650 4 $a Geophysics. $3 535228
690 $a 0373
710 2 $a Saint Louis University. $3 1020558
773 0 $t Dissertation Abstracts International $g 69-07B.
790 $a 0193
790 1 0 $a Zhu, Lupei, $e advisor
791 $a Ph.D.
792 $a 2008
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3324154