本文選題：有限單元法　切入點(diǎn)：最小二乘法　出處：《成都理工大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：激發(fā)極化法是當(dāng)前在尋找金屬礦產(chǎn)中一種被廣泛應(yīng)用的一種方法,它以分辨率高和工作效率高的特點(diǎn)受到了一致的肯定。在雙頻激電實(shí)際工作中,常用視頻散率P和視電阻率ρ來對異常進(jìn)行評價(jià),對異常有時(shí)難以做出準(zhǔn)確的解釋。因而為突出與金屬礦密切相關(guān)的激電異常,壓制干擾因素異常,對這兩種參數(shù)進(jìn)行乘除變換,得到一個(gè)新的參數(shù),定義為視激電率J,旨在通過視激電率J來提取異常的二次信息,并在實(shí)例上進(jìn)行應(yīng)用研究。本文首先介紹了有限單元法正演理論和最小二乘法反演理論,并且為了研究視激電率J的可行性,應(yīng)用有限單元法理論來建立正演模型,觀察到明顯的效果后,將視激電率J應(yīng)用于云南某銅多金屬礦幅頻激電勘探。在對該礦區(qū)進(jìn)行幅頻激電掃面,得到研究區(qū)域的實(shí)測P和ρ的數(shù)據(jù)值的基礎(chǔ)上,對這兩種參數(shù)的異常特征進(jìn)行分析;再將P除以ρ得到的本文需要的視激電率J參數(shù),得到視激電率的異常特征,并與視頻散率和視電阻率的異常特征進(jìn)行對比,找出三種參數(shù)異常特征的異同,對比它們反映場源體特征的效果。通過對研究區(qū)物性參數(shù)和地質(zhì)概況的分析,表明該地區(qū)反映銅多金屬礦(化)的有效異常為低阻高極化。根據(jù)掃面獲得的電阻率和極化率結(jié)果圈定了三個(gè)異常帶,并推斷其中一個(gè)為高阻高極化,另兩個(gè)為低阻高極化帶。為了判斷上述異常帶極化體的范圍、深度及產(chǎn)狀等特征,在異常明顯而且連續(xù)的地方布置精測剖面,進(jìn)行大功率中間梯度方法、磁法及偶極-偶極幅頻激電測深,并對測深數(shù)據(jù)進(jìn)行最小二乘法反演,繪制擬斷面。在對三種異常對比分析的基礎(chǔ)上,結(jié)合研究區(qū)地質(zhì)和物性參數(shù)特征分析研究,獲得如下結(jié)論:本區(qū)兩個(gè)低阻高極化帶礦化現(xiàn)象比較普遍,其中Y3異常帶三種參數(shù)異常對應(yīng)好,與已知礦點(diǎn)異常特征相似,推斷其視頻散率異常均由蝕變長石石英砂巖底板與粉砂質(zhì)板巖接觸的層間破碎帶中的銅礦引起,推測成礦可能性較大,Y2異常區(qū)激電異常復(fù)雜多變,需進(jìn)一步詳查;高阻高極化異常帶推測是由高阻體(淺部石英脈)或?qū)儆陔x子導(dǎo)體的固體電解質(zhì)與周圍溶液形成的雙電層引起;視激電率異常對突出有意義異常、壓制干擾異常有較好的效果。
[Abstract]:The method of induced polarization is a widely used method in searching for metal minerals at present. It has been confirmed by the characteristics of high resolution and high working efficiency. Video dispersion P and apparent resistivity 蟻 are commonly used to evaluate anomalies, and it is sometimes difficult to make an accurate explanation of anomalies. Therefore, in order to highlight the induced anomalies closely related to metal mines, the abnormal interference factors are suppressed. By multiplying and dividing the two parameters, a new parameter is obtained, which is defined as the apparent ionization rate (J), which is used to extract the secondary information of the anomaly through the apparent ionization rate (J). In this paper, the forward modeling theory of finite element method and the least square inversion theory are introduced, and in order to study the feasibility of apparent ionization rate J, the forward modeling is established by using the finite element method theory. The apparent ionization rate J was applied to the amplitude-frequency induced electric prospecting of a copper polymetallic ore deposit in Yunnan Province after the obvious effect was observed. On the basis of the amplitude-frequency excitation sweep surface of the mining area, the measured values of P and 蟻 in the study area were obtained. The anomalous characteristics of the two parameters are analyzed, and then the abnormal characteristics of the apparent ionization rate are obtained by dividing P by 蟻, and the anomalous characteristics of the apparent ionization rate are compared with those of the video divergence rate and the apparent resistivity. This paper finds out the similarities and differences of the abnormal characteristics of three parameters, compares their effects on reflecting the characteristics of the field source body, and analyzes the physical parameters and geological profiles of the study area. It is shown that the effective anomaly reflecting copper polymetallic ore in this area is low resistivity and high polarization. According to the results of resistivity and polarizability obtained from sweep surface, three anomalous zones are delineated, and one of them is deduced to be high resistivity and high polarization. The other two are low resistivity and high polarization zone. In order to judge the range, depth and occurrence of the polarization body in the above anomalous zone, fine profile is arranged in the place where the anomaly is obvious and continuous, and the high-power intermediate gradient method is carried out. Magnetic method and dipole-dipole amplitude-frequency induced sounding are used to invert the bathymetric data and draw the pseudo section. On the basis of the comparison and analysis of the three anomalies, the characteristics of geological and physical parameters in the study area are analyzed and studied. The results are as follows: the mineralization of two low-resistivity and high-polarization zones in this area is quite common, and the three parameter anomalies of Y3 anomaly zone correspond well, which are similar to the characteristics of known ore spot anomalies. It is inferred that the anomaly of video dispersion rate is caused by copper in the interlaminar fracture zone where the base plate of altered feldspar quartz sandstone and silty slate contact with each other. It is inferred that the possibility of mineralization is more complicated and changeable in the anomalous area of Y2 anomaly, which needs further detailed investigation. The high resistivity and high polarization anomaly zone is supposed to be caused by the double electric layer formed by the high resistivity body (shallow quartz vein) or the solid electrolyte which belongs to ionic conductor and the surrounding solution, and the abnormal apparent ionization rate has a good effect on outburst of significant anomaly and suppression of interference anomaly.
【學(xué)位授予單位】：成都理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：P631.3;P618.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前4條

1 李才明，萬新南，，陳利群;物探異常的間接模式識別[J];成都理工學(xué)院學(xué)報(bào);1996年01期

2 熊彬,阮百堯;電位雙二次變化二維地電斷面電阻率測深有限元數(shù)值模擬[J];地球物理學(xué)報(bào);2002年02期

3 吳俊華;袁承先;趙贛;;隱伏礦體的預(yù)測理論、探測方法及發(fā)展現(xiàn)狀[J];地質(zhì)找礦論叢;2010年03期

4 陳本池,李金銘,魏文博;起伏地形條件下固定點(diǎn)源測深法定量解釋研究[J];現(xiàn)代地質(zhì);1998年01期

相關(guān)博士學(xué)位論文 前1條

1 劉小軍;大地電磁聚焦反演成像方法研究[D];同濟(jì)大學(xué);2007年

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