本文選題：渭河盆地　切入點：甘肅黑方臺　出處：《長安大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：區(qū)域地殼構(gòu)造活動是由于地殼內(nèi)部構(gòu)造運動引起的物質(zhì)活動形式,影響地區(qū)地貌的形成和變化,以及為地殼運動與形變提供動力基礎(chǔ),而地質(zhì)災(zāi)害的發(fā)生往往也與區(qū)域地殼構(gòu)造活動密不可分。在中國大陸構(gòu)造體系中,位于大陸中部的黃土高原區(qū)域,新生代以來構(gòu)造活動活躍,地質(zhì)災(zāi)害頻發(fā),比較典型的區(qū)域是位于青藏東緣與鄂爾多斯地塊交界處的渭河盆地,現(xiàn)今地殼構(gòu)造活動十分活躍,導(dǎo)致地質(zhì)災(zāi)害頻發(fā)尤以地裂縫、地震災(zāi)害最為廣泛和典型。此外,與渭河盆地成一脈體系的甘青區(qū)域也是地質(zhì)災(zāi)害多發(fā)區(qū),以黃土滑坡災(zāi)害最為嚴(yán)重。因此,開展上述區(qū)域地殼構(gòu)造運動與變形、地質(zhì)災(zāi)害發(fā)生機制的研究,對掌握區(qū)域現(xiàn)今地殼構(gòu)造活動的演化及其與地質(zhì)災(zāi)害相互關(guān)系、地質(zhì)災(zāi)害防治減災(zāi)等具有有重要的理論和現(xiàn)實意義�；诖�,本文采用有限元數(shù)值分析方法,以高精度GPS監(jiān)測資料做為約束與檢核條件,綜合多學(xué)科基礎(chǔ)理論與地質(zhì)地球物理資料,構(gòu)建了渭河盆地地區(qū)二維與三維有限元模型,獲得了渭河盆地區(qū)域現(xiàn)今地殼構(gòu)造活動特征,并結(jié)合區(qū)域地殼運動與深部動力學(xué)過程探討了區(qū)域性構(gòu)造活動機制、斷層構(gòu)造活動特性,以及深入剖析了研究域地質(zhì)災(zāi)害發(fā)生與區(qū)域構(gòu)造活動的內(nèi)在聯(lián)系。此外,以甘青地區(qū)最為典型的黑方臺黃土滑坡災(zāi)害為例,利用有限元數(shù)值模擬法分自重作用和水土飽和度兩類情況下,研究了黃土滑坡失穩(wěn)破壞的機制,獲得了滑坡各階段變形情況,并對坡面測點進(jìn)行了位移折線圖分析,初步獲得了灌溉型黃土滑坡失穩(wěn)普遍規(guī)律,加深了對滑坡災(zāi)害演化的理解。本文主要的研究內(nèi)容及成果如下:(1)詳細(xì)論述了大地測量技術(shù)在區(qū)域構(gòu)造活動及地質(zhì)災(zāi)害研究中的應(yīng)用,重點介紹了有限元法在地殼構(gòu)造活動及地質(zhì)災(zāi)害模擬研究中的優(yōu)勢。(2)利用區(qū)域地質(zhì)地球物理勘測成果,以邊界區(qū)域高精度GPS監(jiān)測成果作為地表及邊界約束,建立了渭河盆地地殼二維與三維有限元模型,并以模型內(nèi)部實測GPS位移作為檢核條件,驗證了模型的可靠性。(3)利用構(gòu)建的渭河盆地有限元模型,反演獲得了渭河盆地現(xiàn)今地殼構(gòu)造活動特征,及區(qū)域內(nèi)主干斷裂現(xiàn)今活動速率與不同深度斷裂應(yīng)力變化特征,并結(jié)合區(qū)域構(gòu)造動力學(xué)背景,探討了區(qū)域構(gòu)造活動與地裂縫、地震災(zāi)害的內(nèi)在關(guān)系。(4)以典型黃土滑坡為研究對象,利用有限元強度折減法分別在自重與水土飽和度條件下對滑坡穩(wěn)定性進(jìn)行了模擬計算,獲得了滑坡滑動過程中各階段塑性變化特征,并結(jié)合實地考察資料研究了坡體臨空面位移變化趨勢,初步掌握了滑坡失穩(wěn)破壞演化機理。
[Abstract]:Regional crustal tectonic activity is a form of material activity caused by tectonic movement within the crust, which affects the formation and change of landforms in the region, and provides a dynamic basis for crustal movement and deformation. The occurrence of geological hazards is often closely related to the regional crustal tectonic activities. In the continental tectonic system of China, the Loess Plateau region in the middle of the continent has been active in tectonic activity since the Cenozoic, and geological disasters occur frequently. The typical area is the Weihe basin located at the junction of the eastern margin of Qinghai-Tibet and the Ordos block. The crustal tectonic activity is very active, which leads to frequent geological disasters, especially the ground fractures, and the earthquake disaster is the most extensive and typical. The Gansu and Qing regions, which form the same vein system as Weihe Basin, are also prone to geological disasters, especially the loess landslide. Therefore, the study on the crustal tectonic movement, deformation and the mechanism of geological hazards in the above-mentioned regions is carried out. It is of great theoretical and practical significance to understand the evolution of the present crustal tectonic activity and its relationship with geological hazards, and to prevent and reduce geological disasters. Based on this, the finite element numerical analysis method is used in this paper. Taking the high precision GPS monitoring data as the constraint and checking condition, the two-dimensional and three-dimensional finite element models of Weihe Basin are constructed by synthesizing the multidisciplinary basic theory and geological geophysical data. The characteristics of present crustal tectonic activity in Weihe basin are obtained, and the regional tectonic active mechanism and fault tectonic active characteristics are discussed in combination with regional crustal movement and deep dynamic process. In addition, taking Heifangtai loess landslide disaster in Ganqing area as an example, the inherent relationship between geological hazards and regional tectonic activities in the study area is deeply analyzed. In this paper, the mechanism of loess landslide instability and failure is studied by using finite element numerical simulation method, which is divided into two types: deadweight action and soil and water saturation, and the deformation of landslide in different stages is obtained, and the displacement profile of the measured points on the slope is analyzed. The general law of instability of irrigated loess landslide is obtained preliminarily. The main contents and results of this paper are as follows: (1) the application of geodetic technology in the study of regional tectonic activities and geological hazards is discussed in detail. The advantage of finite element method in the study of crustal tectonic activity and geological hazard simulation is emphatically introduced. Using the regional geophysical survey results, the high-precision GPS monitoring results in the boundary area are taken as the surface and boundary constraints. The two-dimensional and three-dimensional finite element models of the crust of Weihe basin are established, and the GPS displacement measured inside the model is used as the check condition to verify the reliability of the model. The characteristics of present crustal tectonic activity in Weihe basin, the present active rate of main faults and the stress variation of faults at different depths in Weihe basin are obtained by inversion. Combined with the regional tectonic dynamic background, the regional tectonic activity and ground fractures are discussed. Taking the typical loess landslide as the research object, the stability of the landslide is simulated by using the finite element strength reduction method under the condition of gravity and water and soil saturation, respectively. The characteristics of plastic variation in each stage of landslide sliding are obtained, and the trend of displacement change on the face of slope is studied with field investigation data, and the evolution mechanism of landslide instability and failure is preliminarily grasped.
【學(xué)位授予單位】：長安大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：P548;P694

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 許才軍,晁定波,劉經(jīng)南,陶本藻,張德涵;用大地測量資料反演青藏高原構(gòu)造應(yīng)力場的初步嘗試[J];測繪學(xué)報;1997年02期

2 劉峽;傅容珊;楊國華;孫東平;董運宏;韓月萍;;用GPS資料研究華北地區(qū)形變場和構(gòu)造應(yīng)力場[J];大地測量與地球動力學(xué);2006年03期

3 徐菊生,袁金榮,高士鈞,賴錫安,李延興,黎凱武,劉烈昭;利用GPS觀測結(jié)果研究華北地區(qū)現(xiàn)今構(gòu)造應(yīng)力場[J];地殼形變與地震;1999年02期

4 秦小軍,周碩愚,吳云;現(xiàn)今板塊、塊體運動定量模型的發(fā)展[J];地殼形變與地震;1999年02期

5 李方全,王連捷;華北地區(qū)地應(yīng)力測量[J];地球物理學(xué)報;1979年01期

6 臧紹先,吳忠良,寧杰遠(yuǎn),鄭斯華;中國周邊板塊的相互作用及其對中國應(yīng)力場的影響——(Ⅱ)印度板塊的影響[J];地球物理學(xué)報;1992年04期

7 劉峽;馬瑾;傅容珊;楊國華;紹志剛;鄭智江;;華北地區(qū)現(xiàn)今地殼運動動力學(xué)初步研究[J];地球物理學(xué)報;2010年06期

8 傅容珊,黃建華,李力剛,常筱華;青藏高原隆升三階段模型的數(shù)值模擬[J];地學(xué)前緣;2000年04期

9 梁海華,丁中一,潘懋,侯建軍,鄭文濤,劉錫大;吐魯番-哈密盆地中新生代構(gòu)造變形的數(shù)值模擬分析[J];地震地質(zhì);1997年04期

10 王連捷;吳珍漢;王薇;孫東生;;青藏高原中段現(xiàn)今構(gòu)造應(yīng)力場的數(shù)值模擬[J];地質(zhì)力學(xué)學(xué)報;2006年02期

相關(guān)博士學(xué)位論文 前1條

1 王敏;GPS觀測結(jié)果的精化分析與中國大陸現(xiàn)今地殼形變場研究[D];中國地震局地質(zhì)研究所;2009年

，

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