【摘要】：地震地下流體(以下簡稱地下流體)觀測,是基于震前地下流體受構(gòu)造影響產(chǎn)生變化這一機(jī)理進(jìn)行的觀測手段。實(shí)踐表明,地下流體觀測不可避免的受到多種因素的影響,由于不同觀測點(diǎn)觀測條件的差異,其受不同影響因素的影響程度也不盡相同。如氣象因素中的氣壓、降水,人文活動中的抽水、注水,以及荷載等干擾因素,都可能使地下流體的物理性質(zhì)、化學(xué)性質(zhì)發(fā)生變化,而這些干擾信息可能與震前的前兆異常信息交織在一起。因此研究地下流體觀測中的干擾因素,對于識別與提取地震前兆信息及對認(rèn)識含水層特性至關(guān)重要,有效分析和提取地下流體觀測中的影響因素,對深入認(rèn)識前兆觀測資料和發(fā)現(xiàn)前兆異常具有重要意義。本文系統(tǒng)研究了鄂爾多斯塊體南緣地下流體觀測中典型干擾異常(降雨、河水洪峰、氣壓等荷載因素)的影響特征,指出降雨對鳳翔井水位影響明顯,并在一定范圍內(nèi)與水位變化呈指數(shù)相關(guān)關(guān)系,深入研究發(fā)現(xiàn),降雨通過荷載效應(yīng)、滲入斷層及改變水位埋深三種途徑影響區(qū)域構(gòu)造應(yīng)力場,并可能觸發(fā)區(qū)內(nèi)中、強(qiáng)地震活動;對雙王井水位與渭河洪峰關(guān)系的分析結(jié)果顯示,洪峰荷載對雙王井水位的加載系數(shù)處于0.84~1.03之間,這一分析結(jié)果可有效的消除洪峰荷載對水位的影響;對于周至深層承壓井,可通過對水位的氣壓效率和相關(guān)系數(shù)來消除氣壓對水位的影響,當(dāng)氣壓效率或相關(guān)系超出正常范圍時,研究區(qū)內(nèi)可能會發(fā)生中、強(qiáng)地震。此外,本文還清理了1980~2010年30年期間鄂爾多斯南緣及鄰近地區(qū)地震事件42個,涉及地下流體測點(diǎn)64個,共計流體測項震例168個,并從測項、震前異常時間、異常形態(tài)三個方面對流體前兆異常進(jìn)行了統(tǒng)計,統(tǒng)計結(jié)果顯示以測項分類統(tǒng)計水(氣)氡所占比例較大(占47%);按震前異常時間統(tǒng)計以的短期異常為主(占47%);按異常形態(tài)統(tǒng)計以高值異常為主(占60%)。對統(tǒng)計樣本的前兆異常持續(xù)時間與震中距統(tǒng)計結(jié)果顯示,異常持續(xù)時間越長,震中距越小,可以理解為異常最先出現(xiàn)在震源區(qū)附近,隨著時間持續(xù),異常有向外擴(kuò)散的趨勢。
[Abstract]:The observation of seismic underground fluid (hereinafter referred to as underground fluid) is based on the mechanism of tectonic change of underground fluid before earthquake. The practice shows that the observation of underground fluid is inevitably influenced by many factors, and the degree of influence of different factors is different due to the difference of observation conditions at different observation points. For example, atmospheric pressure, precipitation, pumping, water injection, and loads in human activities may all cause changes in the physical and chemical properties of underground fluids. The interference information may be intertwined with the precursory anomaly information before the earthquake. Therefore, it is very important to study the interference factors in the observation of underground fluid to identify and extract the seismic precursor information and to recognize the characteristics of the aquifer, and to analyze and extract the influencing factors in the observation of underground fluid effectively. It is of great significance to understand the precursory observation data and find precursory anomalies. In this paper, the influence characteristics of typical disturbance anomalies (rainfall, river water Hong Feng, pressure and other load factors) in the underground fluid observation of the southern edge of Ordos block are systematically studied, and it is pointed out that rainfall has obvious influence on the water level of Fengxiang well. It is found that rainfall affects regional tectonic stress field through load effect, infiltration of fault and change of depth of water level through load effect, and may trigger strong earthquake activity in the region. The analysis of the relationship between Shuangwang well water level and Hong Feng of Weihe River shows that the loading coefficient of Hong Feng load on water level of Shuangwang well is between 0.84 and 1.03, which can effectively eliminate the influence of Hong Feng load on water level. The influence of air pressure on water level can be eliminated by the pressure efficiency and correlation coefficient of water level. When the pressure efficiency or the relation between pressure and pressure is beyond the normal range, moderate and strong earthquakes may occur in the study area. In addition, 42 earthquake events in the southern margin of Ordos and adjacent areas during the period of 1980 to 2010 have been cleared, involving 64 underground fluid sites, a total of 168 fluid term seismograms, and the anomalous time before the earthquake. Three aspects of abnormal morphology are used to calculate the precursory anomalies of fluid. The statistical results show that the proportion of radon in water (gas) is larger (47%), the short-term anomaly (47%) and the high value anomaly (60%) are dominant in the statistics of water (gas) according to the abnormal time before the earthquake. The results show that the longer the duration of the anomaly, the smaller the epicentral distance is, which can be understood as the first occurrence of the anomaly near the focal area, and the tendency of the anomaly to spread outward with the duration of the anomaly.
【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】：P315.7

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 陸明勇;;地殼形變與地下水相互作用及“雙力源”前兆觀點(diǎn)[J];大地測量與地球動力學(xué);2006年01期

2 張昭棟,鄭金涵,耿杰,王忠民,魏煥;地下水潮汐現(xiàn)象的物理機(jī)制和統(tǒng)一數(shù)學(xué)方程[J];地震地質(zhì);2002年02期

3 黃輔瓊;陳楻;白長清;張晶;晏銳;楊明波;蘭叢欣;張曉東;江在森;;八寶山斷層的變形行為與降雨及地下水的關(guān)系[J];地震學(xué)報;2005年06期

4 成爾林,張美芳;鄂爾多斯塊體周邊的地震活動性及地震機(jī)制[J];地震研究;1986年01期

5 袁小沼，，楊永勝，趙彥霞;氣象變化與邢臺地震關(guān)系初探[J];地震研究;1996年04期

6 方煒,劉春,張春生;鄂爾多斯塊體周緣中強(qiáng)地震序列類型及其活動特征[J];地震研究;2004年03期

7 燕明芝,李曉峰,張昱,鄭衛(wèi)平,張?zhí)K平,張小美;德令哈6.6級地震前甘肅地區(qū)前兆異常的初步分析[J];高原地震;2003年03期

8 張昱;陳瑤;李春燕;;2003~2004年岷縣—卓尼地震與甘肅東部地區(qū)水化異常的關(guān)系探討[J];高原地震;2007年03期

9 王吉易,宋貫一,曹志成,鄭云貞,張子廣,范雪芳,黃輔瓊,楊明波;地下水誘發(fā)的淺層前兆異常及其機(jī)理與有關(guān)的地震預(yù)報問題(2)[J];華北地震科學(xué);2002年03期

10 薛宏運(yùn);鄂爾多斯地塊周圍的地震活動性[J];山西地震;1983年01期

本文編號：2263474