The Study Of Nonlinear Conjugate Gradients Algorithm For 2D Magnetotelluric Inversion And Its Application In Duobaoshan Deposit Clusters

The Duobaoshan ore concentration area is located in the northeast part of Xing'an-Mongolia orogenic belt,and west side of the boundary fault between Xing'an block and Songnen block.This area is a tectonic overprinting and conversion area by the Paleo-Asian tectonic domain,the Mongolia-Okhotsk tectonic domain and Paleo-Pacific tectonic domain.According to the tectonic-magma cycle,isotopic age,contact relationship between magmatic rocks and surrounding rock,the magmatic activity in this area can be divided into four sub-periods of Caledonian,Variscan,Yanshanian Stage and the himalayan period due to its frequent structure.Due to it's multi-stage and multi-stage magmatic activity,which produces a wide range of magmatic rocks with extensive distribution and provides important geological conditions for many kinds of metal mineralization.For these favorable ore-forming condition,large number and volume of ore deposits as composite genetic types,this area has been the hot-point area for both ore-prospecting and metallogenic theory for tens of years.The Magnetotelluric has been widely used and drawn geophysicist's attention in all aspects of Geophysics,such as geoelectric structure of crust-mantle,engineering geology and environmental geology,concealed metallic mine exploration,Geothermal field survey,Oil and Gas Census and Exploration,etc.recently one-dimensional and two-dimensional inversion methods are often used for data inversion interpretation.Nonlinear conjugate gradient has the dual advantage,that fast convergence of Quasi-Newton's method and program simple of the steepest descent method,which makes it become one of the important two-dimensional inversion methods in practice.This thesis dose the 973 Subject on the basis of “Study on the Metallogenic Potentiality and Strategy of large Metal Deposits”.Based on the previous research results,three sections of data profile were carried out by using EH-4 electromagnetic imaging system in the village of Duobaoshan Township,Nenjiang County,and the geological prospecting area was surveyed and further geophysical evidence was provided The Through the TE,TM mode,depending on the resistivity profile analysis,combined with the relevant geological data to complete the relevant geological interpretation.To provide a scientific basis and basic information for the comprehensive investigation and technical methods suitable for the mine area for the later period,and to provide further guidance for the scientific research and production work in the region.