發(fā)布時(shí)間：2018-03-30 18:16

  本文選題：大地電磁測(cè)深　切入點(diǎn)：阻抗相位　出處：《成都理工大學(xué)》2015年碩士論文

【摘要】：大地電磁測(cè)深阻抗相位參數(shù)特性分析,這對(duì)于解決淺橫向電性不均勻體導(dǎo)致區(qū)域構(gòu)造中水平均勻的電場(chǎng)發(fā)生畸變問(wèn)題和提高反演的準(zhǔn)確性都顯出較好的效果。本文對(duì)大地電磁阻抗相位的抗畸變特性和靈敏度特性進(jìn)行初步研究。對(duì)阻抗相位張量、視電阻率和阻抗相位一維聯(lián)合反演進(jìn)行了理論模型的數(shù)值模擬和計(jì)算。初步討論了阻抗相位張量在淺部不均勻體模型中抗畸變的作用和聯(lián)合反演對(duì)于降低反演多解性的效果。論文對(duì)近地表非均勻體引起電場(chǎng)畸變進(jìn)行了物理解釋,對(duì)相位張量公式進(jìn)行了推導(dǎo)和計(jì)算。用相位張量分析了加入電場(chǎng)畸變的單點(diǎn)模型,并且與傳統(tǒng)的Swift方法進(jìn)行了對(duì)比,當(dāng)受到淺部小不均勻體的電場(chǎng)畸變時(shí),Swift方法無(wú)法給出正確的電性主軸方位角。并且分析了淺部不均勻體的三維模型下的相位張量,在三維情況下,相位張量可以不受地表淺部不均勻體的影響,但能夠反映該頻率深度下電阻率橫向變化最大的方向。論文根據(jù)均勻半空間的靈敏度函數(shù)和大地電磁響應(yīng)曲線的斜率,對(duì)均勻半空間和層狀模型(電阻率大于1Ω?m)的靈敏度進(jìn)行了分析,對(duì)不同電阻率、頻率和深度下的視電阻率和阻抗相位靈敏度做了對(duì)比。結(jié)果表明,阻抗相位資料的靈敏度要比視電阻率高。本文使用C++軟件編寫(xiě)的視電阻率、阻抗相位和聯(lián)合反演的算法。通過(guò)多種理論模型的反復(fù)試驗(yàn)和對(duì)比,認(rèn)為相位反演在反演速度上更有優(yōu)勢(shì),而視電阻率反演要比相位反演更穩(wěn)定一些。當(dāng)初始模型和真實(shí)模型相差太遠(yuǎn)時(shí),視電阻率反演在大多數(shù)情況下會(huì)發(fā)散,而聯(lián)合反演具有相位反演和視電阻率反演的共同優(yōu)勢(shì),即在保持反演結(jié)果正確的前提下,其收斂速度也比較快。
[Abstract]:Analysis of magnetotelluric impedance phase parameters to solve the shallow lateral inhomogeneity leads to show good results in uniform electric field tectonic level distortion problem and improve the retrieval accuracy. This paper makes a preliminary study of the magnetotelluric impedance phase distortion resistance characteristics and sensitivity characteristics. The impedance phase tensor. The apparent resistivity and impedance phase inversion of one-dimensional numerical simulation and theoretical calculation model. Preliminary discussed the impedance phase tensor in shallow inhomogeneous bodies in the model of anti distortion and joint inversion of multiple solutions to reduce the inversion effect. The near surface inhomogeneities caused by electric field distortion is explained. The phase tensor formulas were deduced and calculated. Using the phase tensor analysis of single point model with electric field distortion, and with the traditional Swift method of By contrast, when the shallow small uneven body electric field distortion, electrical axis Swift method can not give the correct angle. And analyzed the phase tensor three-dimensional model of shallow inhomogeneous bodies under, in the three-dimensional case, the phase tensor can not the influence of uneven shallow surface, but can the direction of the lateral resistivity changes reflect the maximum frequency. According to the depth of the slope of the homogeneous half space sensitivity function and magnetotelluric response curve, the homogeneous half space and layered model (resistivity greater than 1? M) sensitivity analysis was carried out on different resistance, comparison of apparent resistivity and impedance phase sensitivity frequency and depth done. The results show that the sensitivity of impedance phase data than the apparent resistivity of high resistivity. This paper used to prepare the C++ software, and the impedance phase inversion algorithm. The theoretical model through a variety of The repeated test and contrast, think more in the inversion phase inversion speed advantage, and the apparent resistivity inversion than phase inversion is more stable. When the initial model and the real model is too far, the apparent resistivity inversion in most cases will diverge, and joint inversion with phase inversion and resistivity inversion of the common advantage, i.e. in the inversion results correct premise, its convergence speed is faster.

【學(xué)位授予單位】：成都理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：P631.325

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 晉光文;大地電磁阻抗相位資料的特點(diǎn)和應(yīng)用[J];地震地質(zhì);1988年04期

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本文編號(hào)：1687062