本文選題：GPS地震學(xué) + CORS�。� 參考：《西南交通大學(xué)》2014年博士論文

【摘要】：GPS (Global Positioning System)地震學(xué)作為20世紀(jì)末的一門新興學(xué)科,在淺源強(qiáng)震地殼形變研究中占有明顯的優(yōu)勢(shì)。首先,時(shí)間尺度上它可實(shí)現(xiàn)數(shù)秒到數(shù)年的地殼形變監(jiān)測(cè)。其次,該觀測(cè)手段可直接提供時(shí)變位移場(chǎng)觀測(cè)信息,彌補(bǔ)了傳統(tǒng)觀測(cè)手段在強(qiáng)震觀測(cè)時(shí)出現(xiàn)的不足,如飽和、漂移等現(xiàn)象。多個(gè)固定GPS測(cè)站構(gòu)成的CORS (Continuously Operating Reference System)觀測(cè)網(wǎng)絡(luò)近幾年來(lái)在地震地殼形變監(jiān)測(cè)方面發(fā)展迅猛。然而,深入、系統(tǒng)地將CORS運(yùn)用于地震地殼形變,進(jìn)一步發(fā)掘其應(yīng)用潛能還亟待發(fā)展。本文在此背景下,以四川2008年Ms8.0汶川地震和2013年Ms7.0蘆山地震為主要研究對(duì)象,通過(guò)解算分析區(qū)域CORS觀測(cè)資料,主要研究了三部分內(nèi)容,分別為：汶川地震前后,板塊運(yùn)動(dòng)特性的探索；高頻GPS地震信號(hào)的提取和分析；準(zhǔn)實(shí)時(shí)地震三要素(發(fā)震時(shí)刻、震源和震級(jí))的反演。本文的研究工作和貢獻(xiàn)主要表現(xiàn)在如下幾個(gè)方面：1.分析了四川盆地CORS站在汶川地震前后的運(yùn)動(dòng)特征。利用GAMIT/GLOBK解算出的以日為單位的坐標(biāo)時(shí)序,通過(guò)時(shí)序建模對(duì)比分析了區(qū)域CORS站在汶川地震前后的水平運(yùn)動(dòng)速度場(chǎng)和垂直方向的振幅,初步確認(rèn)汶川地震改變了四川盆地原有的運(yùn)動(dòng)特性。具體表現(xiàn)在：震后共模誤差的第一貢獻(xiàn)率明顯降低了20%-40%；地震后PIXI MYAN、CHDU等站水平運(yùn)動(dòng)速度場(chǎng)改變明顯,但YAAN、QLAI等測(cè)站處于閉鎖狀態(tài)；四川盆地CORS站在U分量的平均周年振幅在震前一年明顯偏大,此后逐年減小。2.以2013年4月20日的Ms7.0級(jí)蘆山地震為例,高頻GPS信號(hào)的時(shí)頻分析表明,地震對(duì)高頻CORS站時(shí)序的頻譜影響范圍集中在0.02Hz-0.2Hz,與無(wú)震時(shí)相比,其功率譜密度明顯偏大。10Hz的GPS位移數(shù)據(jù)和200Hz的強(qiáng)震儀加速度數(shù)據(jù)通過(guò)卡爾曼濾波融合后,可獲取更加完整和客觀的200Hz位移波形,表明兩種技術(shù)手段之間可相互取長(zhǎng)補(bǔ)短。3.利用S變換和本文提出的三維搜索法分析近震高頻CORS站坐標(biāo)時(shí)序,在震后60s內(nèi)可得出與實(shí)際情況較相符的發(fā)震地點(diǎn)和時(shí)刻。利用CORS站觀測(cè)到的峰值位移和震中距,在300s內(nèi)擬合出蘆山地震的面波震級(jí)為6.6級(jí)。矩震級(jí)在震后數(shù)小時(shí)內(nèi),通過(guò)多個(gè)CORS站的靜態(tài)位移,利用fastCMT算法也可得出與美國(guó)地質(zhì)調(diào)查局相一致的結(jié)果。4.采用差分定位策略時(shí),共模誤差對(duì)區(qū)域CORS網(wǎng)絡(luò)坐標(biāo)時(shí)序的影響不容忽視。主成分濾波能有效減弱共模誤差的影響,無(wú)論是針對(duì)汶川地震前CORS站單日解的連續(xù)觀測(cè)時(shí)序中,還是短時(shí)高頻CORS站的坐標(biāo)時(shí)序,均能使數(shù)據(jù)的均方根(RMS, Root Mean Square)值得到約30%-60%的改善。5.通過(guò)有色噪聲模型建模,利用極大似然估計(jì)法,對(duì)近七年(2006-2012年)單日解CORS站坐標(biāo)時(shí)序的噪聲特性分析表明,四川區(qū)域CORS站的最優(yōu)噪聲模型為白噪聲+閃爍噪聲和白噪聲+冪律噪聲模型,兩者共占到了78%；高頻CORS站坐標(biāo)時(shí)序的譜指數(shù)經(jīng)功率譜估計(jì)在1.6—2之間,可認(rèn)為此時(shí)序噪聲符合白噪聲+隨機(jī)游走模型。
[Abstract]:GPS (Global Positioning system) seismology, as a new subject at the end of the 20th century, has an obvious advantage in the study of crustal deformation of shallow strong earthquakes. First, on a time scale, it can be used to monitor crustal deformation for several seconds to several years. Secondly, the observation method can directly provide time-varying displacement field observation information, which makes up for the shortcomings of traditional observation methods in strong earthquake observation, such as saturation, drift and so on. The continuous operating reference system (cors), which is composed of several fixed GPS stations, has developed rapidly in recent years in the field of crustal deformation monitoring. However, the application of cors to seismic crustal deformation needs to be developed. In this background, the earthquake of Ms8.0 Wenchuan in 2008 and the Lushan earthquake of Ms7.0 in 2013 are taken as the main research objects in this paper. Through the calculation and analysis of the regional cors observation data, three parts are studied: before and after the Wenchuan earthquake. Exploration of plate motion characteristics, extraction and analysis of high frequency GPS seismic signals, inversion of three elements of quasi real time earthquakes (time of occurrence, source and magnitude). The research work and contribution of this paper are as follows: 1. The movement characteristics of cors station in Sichuan basin before and after Wenchuan earthquake are analyzed. By using the coordinate time series calculated by GAMIT / GLOBK, the horizontal velocity field and the amplitude of vertical direction of the cors station before and after the Wenchuan earthquake are compared and analyzed by time series modeling. It is preliminarily confirmed that Wenchuan earthquake changed the original movement characteristics of Sichuan basin. The main results are as follows: the first contribution rate of the common mode error after the earthquake obviously decreased by 20-40, the horizontal velocity field of PIXI MYANN CHDU and other stations changed obviously after the earthquake, but the YAAN-QLAI and other stations were in a closed state. The average annual amplitude of the U component of the cors station in Sichuan Basin is obviously larger one year before the earthquake, and then decreases by 0.2. Taking the Lushan earthquake of Ms7.0 on April 20, 2013 as an example, the time-frequency analysis of high frequency GPS signal shows that the frequency spectrum influence range of the earthquake on the time series of high frequency cors station is 0.02Hz-0.2Hz. When the GPS displacement data with the power spectral density of .10Hz and the acceleration data of the 200Hz strong seismograph are fused by Kalman filter, a more complete and objective 200Hz displacement waveform can be obtained, which shows that the two techniques can complement each other. The coordinate sequence of the high frequency cors station of near earthquakes is analyzed by using S transform and the 3D search method proposed in this paper. Within 60 seconds after the earthquake, the location and time of occurrence can be obtained in accordance with the actual situation. Based on the peak displacement and epicentral distance observed by the cors station, the surface wave magnitude of the Lushan earthquake is estimated to be 6. 6 in 300 s. Within a few hours after the earthquake, the moment magnitude can also be obtained by using FastCMT algorithm through the static displacement of several cors stations, which is consistent with that of the US Geological Survey (USGS). When using differential positioning strategy, the influence of common-mode error on coordinate timing of regional cors network can not be ignored. Principal component filtering can effectively reduce the influence of common-mode error, not only in the continuous observation time series of the single day solution of the cors station before the Wenchuan earthquake, but also in the coordinate time series of the short-time high-frequency cors station. Both make RMS (Root mean Square) worth about 30% to 60% better. By modeling the colored noise model and using the maximum likelihood estimation method, the noise characteristics of the single day solution of the cors station coordinates in the last seven years (2006-2012) are analyzed. The optimal noise models of cors station in Sichuan region are white noise flicker noise and white noise power law noise model, and the spectral exponents of high frequency cors station coordinate sequence are estimated to be between 1.6-2 by power spectrum. It can be considered that this time series noise accords with the white noise random walk model.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2014
【分類號(hào)】：P228.4;P315.7

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 黃丁發(fā),丁曉利,陳永奇,龔濤,熊永良;GPS多路徑效應(yīng)影響與結(jié)構(gòu)振動(dòng)的小波濾波篩分研究[J];測(cè)繪學(xué)報(bào);2001年01期

2 黃立人,馬青;參考框架的一致性及其對(duì)形變分析的影響[J];地殼形變與地震;2001年02期

3 黃立人;地殼運(yùn)動(dòng)的參考框架[J];大地測(cè)量與地球動(dòng)力學(xué);2002年03期

4 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

5 蘇小寧;孟國(guó)杰;胡叢瑋;伍吉倉(cāng);;基于TRACK進(jìn)行GPS單歷元定位[J];大地測(cè)量與地球動(dòng)力學(xué);2009年03期

6 楊博;張風(fēng)霜;韓月萍;;GPS連續(xù)站水平分量時(shí)間序列共模誤差識(shí)別的歐拉-小波法[J];大地測(cè)量與地球動(dòng)力學(xué);2010年03期

7 武國(guó)寧;曹思遠(yuǎn);馬寧;劉建軍;;S變換的時(shí)頻分析特性及其改進(jìn)[J];地球物理學(xué)進(jìn)展;2011年05期

8 王小亞,朱文耀,符養(yǎng),游新兆,王琪,程宗頤,任金衛(wèi);GPS監(jiān)測(cè)的中國(guó)及其周邊現(xiàn)時(shí)地殼形變[J];地球物理學(xué)報(bào);2002年02期

9 栗連弟,戚成柱,李文棟,許秀敏;關(guān)于數(shù)字地震臺(tái)網(wǎng)震級(jí)偏差原因的分析[J];地震地磁觀測(cè)與研究;2004年S1期

10 黃立人;符養(yǎng);;GPS連續(xù)觀測(cè)站的噪聲分析[J];地震學(xué)報(bào);2007年02期

相關(guān)博士學(xué)位論文 前4條

1 易吉良;基于S變換的電能質(zhì)量擾動(dòng)分析[D];湖南大學(xué);2010年

2 符養(yǎng);中國(guó)大陸現(xiàn)今地殼形變與GPS坐標(biāo)時(shí)間序列分析[D];中國(guó)科學(xué)院研究生院（上海天文臺(tái)）;2002年

3 李英冰;固體地球的環(huán)境變化響應(yīng)[D];武漢大學(xué);2003年

4 袁德寶;GPS變形監(jiān)測(cè)數(shù)據(jù)的小波分析與應(yīng)用研究[D];中國(guó)礦業(yè)大學(xué)（北京）;2009年

相關(guān)碩士學(xué)位論文 前1條

1 陳斌;時(shí)頻分析及在地震信號(hào)分析中的應(yīng)用研究[D];成都理工大學(xué);2007年

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