(1. 中南大學(xué) 地球科學(xué)與信息物理學(xué)院，長沙 410083；
2. 中南大學(xué) 有色金屬成礦預(yù)測教育部重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 針對超高密度電法的全四極裝置，采用三角形網(wǎng)格剖分和線性插值的有限單元法進(jìn)行正演模擬，然后對該模擬結(jié)果開展廣義最小二乘正則化反演，反演過程中對模型參數(shù)同時施加光滑模型和背景模型約束以提高反演穩(wěn)定性。以一個低阻雙層結(jié)構(gòu)模型為例，與5種常規(guī)電法進(jìn)行對比，發(fā)現(xiàn)超高密度電法具有數(shù)據(jù)信息量大、反演精度高的優(yōu)點(diǎn)。對一個山谷地形下正方體低阻模型的超高密度電法數(shù)據(jù)進(jìn)行正演和反演模擬，反演結(jié)果表明：該方法在較復(fù)雜地形條件下也能較好地刻畫出異常體的形態(tài)及地下電性的分布，提高物探解釋精度。
關(guān)鍵字: 超高密度電法；全四極裝置；有限單元法；正演模擬；廣義最小二乘反演
（1. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China;
2. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China）
Abstract:According to the full-four-pole array of ultra-high density resistivity method, the triangle mesh subdivision and the finite element method of linear interpolation were used for forward simulation, and then generalized least square regularization for inversion was used for the simulation results. At the same time, the smooth model and background model constraints were imposed in model parameters to improve the stability of inversion. Taking a low resistivity double-layer structure model as an example, ultra-high density resistivity method possesses the advantages of large volume data and high inversion accuracy compared with 5 kinds of conventional resistivity methods. The forward and inversion simulations were carried out on data of low resistance cube under valley terrain model using ultra-high density electrical method. The inversion results show that even under complex terrain conditions this method can portray the shape of abnormal body and underground electrical distribution well, thus, effectively improving the precision of geophysical interpretation.
Key words: ultra-high density resistivity method; full-four-pole array; finite element method; forward simulation; generalized least square inversion
