The Research And Application Of Oil Gas Recognition Technology In Wide Field Electromagnetic Methods

In order to provide technical support and expand exploration results of oil gas reservoirs in Qaidam Basin, the Wide Field subject group of Central South University took the researching missions of wide field electromagnetic methods exploration in the study region. The prospecting area centered on the well3, the total dimension was about100km2, including5measuring lines with each length of10km.This paper supplied the geophysical characteristics and developed the research trials based on the formation resistivity difference; made numerical simulations in the geoelectric models, and founded the forward and inversion research theory of wide field electromagnetic methods applied in the oil-gas exploration; explained the static correction, de-noising, qualitative and quantitative analysis (curve type,pseudo-section map,1D and2D continuum inversion techniques) in processing data of wide field electromagnetic methods. The geological interpretation held the principles of synthesizing wide field, drilling and other research data.Through comprehensive analysis and interpretation on wide field electromagnetic and other geophysical information, this paper told the geophysical difference of stratigraphic structures; detailedly described and studied the development situation of deep strata; and then put forward the favorable areas for reservoir forming; meanwhile presented a set of technical flow to recognize the deep oil and gas resources using with wide field electromagnetic methods.Thus reveals the electric property difference between the gas and non-gas bearing formations, the gas bearing resistivity is relatively higher; Wide field electromagnetic methods have high resolution, and then can recognize the resistivity difference when it’s even too small to recognize by CSAMT; furthermore wide field electromagnetic methods have high exploration accuracy, up to5%in recognizing the stratum depth.