發(fā)布時(shí)間：2018-06-22 13:03

  本文選題：GPS + 汶川地震　； 參考：《中國(guó)地震局地震預(yù)測(cè)研究所》2013年碩士論文

【摘要】：空間大地測(cè)量GPS技術(shù)廣泛應(yīng)用于地殼形變監(jiān)測(cè)以來(lái)，其在孕震形變場(chǎng)識(shí)別，同震位移場(chǎng)觀測(cè)和震后地殼運(yùn)動(dòng)變化監(jiān)測(cè)等方面都發(fā)揮著重要作用，已成為現(xiàn)今研究與地震相關(guān)的地殼形變場(chǎng)的主要手段之一。2008年5月12日，四川省汶川縣發(fā)生了Ms8.0級(jí)地震，因其震級(jí)較大，必然對(duì)周邊地殼形變場(chǎng)產(chǎn)生一定影響，因此，利用GPS數(shù)據(jù)對(duì)震后形變場(chǎng)特征問(wèn)題進(jìn)行研究顯得十分必要。本文以青藏高原東北緣作為研究區(qū)域，基于不同時(shí)段GPS數(shù)據(jù)，對(duì)汶川地震后該區(qū)地殼形變場(chǎng)特征進(jìn)行分析，，論文主要完成了工作如下： 1.基于1999～2007時(shí)段和2007～2009時(shí)段GPS數(shù)據(jù)，討論了震后短期青藏高原東北緣地殼運(yùn)動(dòng)變形特征及其成因問(wèn)題。 通過(guò)對(duì)莊浪河斷裂和祁連山中東段斷裂進(jìn)行跨斷層剖面分析，表明地震前后這兩條斷裂滑動(dòng)速率變化顯著；采用球體位錯(cuò)模型獲得汶川地震同震位移場(chǎng)分布，結(jié)果顯示同震對(duì)這兩條斷裂有一定影響，但更大程度上不是來(lái)自同震，而是由震后形成的；計(jì)算震后一年粘彈性松弛效應(yīng)在青藏東北緣產(chǎn)生的變形，結(jié)果顯示變形很小，可以忽略；反演了龍門(mén)山斷層面上震后余滑的滑動(dòng)分布，再計(jì)算該滑動(dòng)分布在青藏高原東北緣產(chǎn)生的地殼變形，結(jié)果表明震后余滑對(duì)該區(qū)域影響微乎其微，可以忽略；通過(guò)分析地震前后塊體歐拉矢量變化，顯示受同震分布樣式影響，不同塊體震后運(yùn)動(dòng)調(diào)整的差異對(duì)震后變形的形成有重要影響；分析認(rèn)為汶川地震震后短期地殼變形特征的形成不是由現(xiàn)有的震后余滑、粘彈性松弛等變形機(jī)制模型所能解釋的，可能是由于青藏高原東北緣屬于多塊體構(gòu)造系統(tǒng)，震后塊體間的運(yùn)動(dòng)調(diào)整差異使得塊體邊界帶的運(yùn)動(dòng)發(fā)生顯著變化。 2.基于1999～2007、2007～2009和2009～2011時(shí)段GPS數(shù)據(jù)，研究了震后青藏高原東北緣地表形變場(chǎng)特征。 利用最小二乘配置方法獲得青藏高原東北緣地表應(yīng)變率場(chǎng)（包括最大剪應(yīng)變率場(chǎng)和面應(yīng)變率場(chǎng)），分析了區(qū)域地表應(yīng)變率場(chǎng)特征，結(jié)果顯示2007～2009時(shí)段部分區(qū)域地表應(yīng)變率變化顯著，2009～2011時(shí)段則有所恢復(fù)；通過(guò)塊體歐拉矢量法計(jì)算了主要斷裂的滑動(dòng)速率，利用跨斷層剖面分析距斷裂不同尺度處變形特征，結(jié)果表明在2007～2009時(shí)段，托萊山斷裂、冷龍嶺斷裂和金強(qiáng)河斷裂左旋走滑速率明顯增大，斷裂變形在斷裂附近50km范圍內(nèi)尤為顯著，在2009～2011時(shí)段，各斷裂滑動(dòng)速率和跨斷層剖面結(jié)果均與震前1999～2007時(shí)段相差不大。 3.主要斷裂帶深部閉鎖程度與滑動(dòng)虧損分布及其震后變化 為利用GPS地表觀測(cè)資料研究青藏高原東北緣地區(qū)主要斷裂帶應(yīng)變積累狀態(tài)及其在汶川地震后的變化，開(kāi)展了基于負(fù)位錯(cuò)模型反演主要斷裂深部閉鎖程度和滑動(dòng)虧損分布，分析主要斷裂深部應(yīng)變積累特征，以1999～2007年GPS速度場(chǎng)數(shù)據(jù)為約束反演了汶川地震前主要斷裂帶上斷層閉鎖程度和滑動(dòng)虧損分布，進(jìn)一步用2007～2009年、2009～2011年資料反演了汶川地震后主要斷裂帶斷層閉鎖和滑動(dòng)虧損的變化。結(jié)果顯示震前金強(qiáng)河斷裂、毛毛山斷裂和六盤(pán)山斷裂南段震前閉鎖程度強(qiáng)，并且在2007～2009時(shí)段進(jìn)一步增強(qiáng)，2009～2011時(shí)段，托萊山斷裂和冷龍嶺斷裂閉鎖程度有一定增強(qiáng)，金強(qiáng)河斷裂變化不大，閉鎖依然較強(qiáng)，其他斷裂均閉鎖有所減弱，可能受到了日本9.0地震對(duì)該區(qū)域影響。綜合形變場(chǎng)特征認(rèn)為金強(qiáng)河斷裂未來(lái)強(qiáng)震危險(xiǎn)性相對(duì)較高。
[Abstract]:SPATIAL GEODETIC GPS technology has been widely applied to the monitoring of crustal deformation. It has played an important role in the identification of seismogenic deformation field, the observation of the same earthquake displacement field and the monitoring of the change of the crustal movement after the earthquake. It has become one of the main sections of the crustal deformation field related to the earthquake in May 12th, Wenchuan County, Sichuan province. It is necessary to have a certain influence on the deformation field of the surrounding crust because of the large magnitude of the Ms8.0 magnitude earthquake. Therefore, it is necessary to study the characteristics of the deformation field after the earthquake by using the GPS data. This paper takes the northeastern margin of the Qinghai Tibet Plateau as the study area and based on the GPS number of different periods of time, the crustal deformation field of the Wenchuan region after the earthquake is introduced. In line with the analysis, the main work of the paper is as follows:
1. based on the GPS data of 1999~2007 and 2007~2009 periods, the crustal movement and deformation characteristics of the northeast margin of the Qinghai Tibet Plateau and their causes are discussed shortly after the earthquake.
Through the cross fault section analysis of the Zhuanglang River fault and the east part of the Middle East section of the Qilian mountain, it is shown that the slip rates of the two faults are significant changes before and after the earthquake, and the distribution of the seismic displacement field of the Wenchuan earthquake is obtained by using the model of the sphere dislocation. The results show that the same earthquake has a certain effect on the two faults, but to a great extent, it is not from the same earthquake, but not the same shock. After the earthquake, the deformation of the viscoelastic relaxation effect of one year after the earthquake was calculated in the northeastern margin of the Qinghai Tibet Plateau. The results show that the deformation is very small and can be ignored. The slip distribution of the post earthquake on the Longmen Mountain Fault layer is retrieved and the crust deformation caused by the sliding distribution on the northeastern margin of the Qinghai Tibet Plateau is calculated. The results show that the residual slip after the earthquake is on the region. The influence of the Euler vector changes on the block body before and after the earthquake shows that the difference of the post earthquake movement adjustment of different blocks has an important influence on the formation of the post earthquake deformation, and it is considered that the formation of the short-term crustal deformation characteristics after the Wenchuan earthquake is not by the existing post earthquake residual slip and the viscoelasticity. The deformation mechanism model of sexual relaxation may explain that the northeast margin of the Qinghai Tibet Plateau belongs to the multi block structural system, and the movement adjustment difference between the post earthquake blocks makes the movement of the block boundary zone significantly change.
2. based on the GPS data from 1999~20072007 to 2009 and 2009~2011 periods, the characteristics of the surface deformation field in the northeastern margin of the Qinghai Tibet Plateau were studied.
The ground strain rate field (including the maximum shear strain rate field and the surface strain rate field) on the northeastern margin of the Qinghai Tibet Plateau is obtained by using the least square method, and the regional surface strain rate field is analyzed. The results show that the change of the surface strain rate in the part of the 2007~2009 period is significant and the 2009~2011 period is restored; the block Euler vector method is used. The slip rate of the main fracture is calculated, and the deformation characteristics at different scales are analyzed by cross fault section. The results show that in the 2007~2009 period, the Laishan fault, the Leng Long Ling fault and the Jin Qiang River fault are obviously increased, and the fracture deformation is particularly prominent in the 50km fan enclosure near the fault, and in the 2009~2011 period, the fracture slip is slippery. The results of dynamic velocity and cross fault section are not significantly different from those of the 1999~2007 period before the earthquake.
3. the deep block degree and slip loss distribution of major fault zones and their post earthquake changes.
In order to study the strain accumulation state of the main fault zone in the northeastern margin of the Qinghai Tibet Plateau and the changes in the Wenchuan earthquake, a negative dislocation model is used to inverse the depth of the main fault and the slip loss distribution based on the negative dislocation model. The strain accumulation of the main faults is analyzed, and the data of the 1999~2007 year GPS velocity field is taken as the data of 1999~2007 years. The degree of fault atresia and slip loss distribution on the main fault zone before Wenchuan earthquake are retrieved, and the changes of fault locking and slip loss in the main fault zone after Wenchuan earthquake are retrieved from the data of 2007~2009 years and 2009~2011 years. The results show that the Jin Qiang River fault, Maomao Shan fault and the southern segment of six Panshan fault before the earthquake were locked. The degree of the Laishan fault and the cold Long Ling fault is enhanced in the 2009~2011 period, and the faults of the Laishan fault and the Leng Long Ling fault have a certain enhancement. The fault of the Jin Qiang river is not changed, the interlocking is still strong, and the other fractures are locked down, which may be affected by the 9 earthquake in Japan. The risk of future strong earthquakes is relatively high.
【學(xué)位授予單位】：中國(guó)地震局地震預(yù)測(cè)研究所
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2013
【分類(lèi)號(hào)】：P228.4;P542

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 許才軍;劉洋;溫?fù)P茂;;利用GPS資料反演汶川Mw 7.9級(jí)地震滑動(dòng)分布[J];測(cè)繪學(xué)報(bào);2009年03期

2 楊國(guó)華;張風(fēng)霜;武艷強(qiáng);韓月萍;沈午春;楊博;;利用GPS連續(xù)觀測(cè)資料進(jìn)行強(qiáng)震危險(xiǎn)性預(yù)測(cè)的探討[J];地震;2008年01期

3 楊國(guó)華;楊博;張風(fēng)霜;韓月萍;劉峽;;汶川地震對(duì)華北地區(qū)水平形變場(chǎng)影響及有關(guān)含義的討論[J];地震;2009年01期

4 薄萬(wàn)舉;楊國(guó)華;張風(fēng)霜;;汶川M_S8.0地震孕震機(jī)理的形變證據(jù)與模型推演[J];地震;2009年01期

5 何文貴;袁道陽(yáng);葛偉鵬;羅浩;;祁連山活動(dòng)斷裂帶中東段冷龍嶺斷裂滑動(dòng)速率的精確厘定[J];地震;2010年01期

6 顧國(guó)華;;地殼形變與地震前兆探索回顧和展望[J];地震;2012年02期

7 游新兆;楊少敏;王琪;;中國(guó)大陸地殼運(yùn)動(dòng)觀測(cè)研究進(jìn)展[J];地震;2012年02期

8 付廣裕;孫文科;;球體位錯(cuò)理論計(jì)算程序的總體設(shè)計(jì)與具體實(shí)現(xiàn)[J];地震;2012年02期

9 張燕,吳云,施順英,周碩愚,韓尚;GPS時(shí)間序列揭示地震前兆的初步探索[J];大地測(cè)量與地球動(dòng)力學(xué);2005年03期

10 石耀霖;朱守彪;;用GPS位移資料計(jì)算應(yīng)變方法的討論[J];大地測(cè)量與地球動(dòng)力學(xué);2006年01期

相關(guān)博士學(xué)位論文 前1條

1 陳文彬;河西走廊及鄰近地區(qū)最新構(gòu)造變形基本特征及構(gòu)造成因分析[D];中國(guó)地震局地質(zhì)研究所;2003年

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