The Study Of MT Tipper And Application In Uranium And Multimetal Mine Exploration

Tipper,one of the important parameters in MT,is very sensitive to the lateral inhomogeneous change of underground medium.It can be used to judge the fault structure and lithologic boundary to find out the geological environment.At present,there are two methods to use the Tipper: one is to use it as one of the inversion parameters,to carry out joint inversion with the impedance data;the other is to form the pseudo section of the response of each frequency Tipper,and then analyze the data.Although these methods have achieved good application results,the application of Tipper data is still not intuitive.In this paper,the Tipper is studied as a single parameter which can be directly used for analysis.Through two-dimensional forward modeling of several typical models of lithologic interface,fracture and different resistivity ratio,the characteristics of Tipper response are summarized by using the way of derivation of Tipper data.For example,in the result of finding the first derivative of the real part of the Tipper response,the positive abnormal area always corresponds to the low resistance distribution area;in the result of finding the second derivative of the real part of the Tipper response,the observation is made according to the line direction from small to large,in the transverse direction,if the high resistance becomes the low resistance,the second derivative of the real part of the Tipper presents the characteristics of the positive abnormal area,and its interface is located in the center of the abnormal area;if the low resistance The second derivative of the real part of the Tipper is characterized by a negative anomaly zone,and its interface is located in the center of the anomaly zone.Based on the above characteristics,the Tipper data can be used as an independent parameter to intuitively infer the location of resistivity low resistance band,the lateral variation of resistivity and the location of interface after simple processing.Through two application examples of ZTEM survey in Qinghai a area and AMT survey in Xinjiang B area,the characteristics of the range of low resistivity area corresponding to the first derivative of the Tipper real part data are confirmed.The first derivative processing in ZTEM has become a standard process,and the results in area B have been verified by drilling.The forward model is established by drilling in Erlian basin,and inversion and Tipper numerical simulation are carried out for the model.Combined with the characteristics of the Tipper data and the simulation results,it is theoretically proved that it is feasible to use the Tipper as an independent analysis parameter to determine the transverse boundary of the target sand body.In practical application,the method of joint inversion and Tipper data can be used to determine the sand body of the target layer vertically and horizontally,so as to improve the reliability of the data.In conclusion,it is considered that the Tipper data can be used as an independent parameter and intuitively as data interpretation to assist in the analysis of horizontal variation characteristics of underground electrical properties,which enriches the use of Tipper data.