Development of cost effective surface geochemical methods is a real challenge to regional exploration for new large and giant deposits in diverse overburden terrians. New geochemical methods——NAMEG (collection of nanoscale metals in earthgas) and MOMEO (leaching of mobile forms of metals in overburden) have been developed. These two methods have been widely investigated for their usefulness and suitability for strategic reconnaissance surveys with wide spaced sampling for delineation of broad geochemical patterns generating from concealed giant ore deposits.Encouraging results have been obtained. (1) Large regional anomalies occur across large and giantore deposits or metallogenic belts. Methods focused on them can be used to delineate strategic targets for the discovery of giant ore deposits. (2) The methods give a significant response to deep seated mineralization at a depth of over 300 meters. The cover does not mask the mineralization indicators. (3) Use of both methods can obtain more reliable information generated from the deep buried mineralization. (4) MOMEOmethods can be used to estimates the quantity of metals available for mineralization. (5) These new techniques can significantly reduce the geophysical and drilling costs.

The authors made large quantities of research work into the theory of reconstructing underground physical parameter image,the forward and inverse calculation,the computer software,the laboratory ultrasonic model test and the resistivity experimentation based respectively on the distribution of artificial source induced seismic wave,sonic wave,electromagnetic wave and resistivity,and successfully developed the software package for exploration geophysical tomography supported by Windows 95.Three examples of exploration application was given.

Exemplified by 3D Seismic exploration carried out in several large coal mines,this paper has discussed the technique of 3Ddata acquisition and processing as well as the technique of interactive interpretation,and also demonstrated the capability and accuracy of the technique in detecting small sized faults and folds within the vertical depth of 800 m.The technique proved to be effective.

The airborne electric resistance mapping technique lies in the conversion of measured airborne electromagnetic field signal into apparent electric resistance value that reflects underground strata through inversion or graticule transformation technique.With this technique,one can get rid of the difficulties in geological interpretation caused by considerable variation in the measuring work and remarkable difference in response characteristics of different airborne electromagnetic systems.The application of airborne electromagnetic data in Nanggong and Jiayu area has demonstrated good prospects of this technique.

Being a portable and high speed technique,radioisotope X-ray fluorescence analysis method is one of nuclear geophysical prospecting methods.It can be used in the field to measure contents of some elecment in rocks or ores,thus providing important quantitative or semiquantitative data for geological prospecting.The X-ray fluorescence method has been extensively used in many fields.Taking the Longtang lead zinc deeposit as an example,the present paper mainly studies the technical measures and the application of X-ray fluorescence method to the study of metallogenic regularity and the resource assessment of lead zinc ore deposits.

In oil and gas exploration,the seismic method proves to be effective in determining geological interfaces,and high precision gravity survey can observe negative gravity anomalies caused by commercial reservoirs.On the basis of correlation analysis of gravimetric and seismic data,the method for predicting oil and gas reservoirs using the incorrelate property between gravity anomalies caused by oil (gas) pools and geological interfaces is recounted.The model trial and applied examples show it to be effective and applicable.

The authors have put forward the technical idea and method for multi component Rayleigh wave exploration, successfully developed a special multi component Reyleigh wave exploration instrument and, on the basis of applying Rayleigh polarization analysis to the multi component signal analysis of Rayleith wave exploration record,extracted effective Rayleigh wave signal by means of polarization filtering.The downhole and surface application of this instrument in coal mines has demonstrated that,compared with the single component method,the multi component Rayleigh wave exploration can raise signal to noise ratio,exploration depth and reliability to certain extent.

Prospecting test of hidden faults and layer division was carried out by using joint exploration method of shallow seismic refraction and reflection waves at the bridge seat of Shuhe River along Beijing—Shanghai Expressway.The prospecting test was conducted on water surface which is about 300 m wide.The authors used high resolution digtal seismograph ES-2401 and adopted the working method of “five smalls and two highs”,and picked up information of refracted and reflected waves in all directions.These measures enhanced the reliability of geological interpretation,and the prospecting test achieved good results.

The present paper briefly describes the basic principle of electromagnetic shift and shift processing method of low-frequency filtering,and deals in detail with the technique for figuring out optimum extremum time T .With Straton-Chu intergral as the theoretical basis and by means of Green's function in infinite uniform media,the electromagnetic shift describes the propagation process of quasi stationary electromagnetic field in lower half space.Using the electromagnetic shift method to TEM data-processing,one can rather accurately locate local conductive geological bodies,benefit from high processing speed and obtain vivid interpretation result.

The resolution radio of tomographic imaging depends on the acquisition precision of seismic (acoustic) full wave form information.The present paper deals with the collection of characteristic information from seismic (acoustic) full wave form records,the establishment of three wave form records,the establishment of three layer neuron network model,the application of neuron network to the information collection of seismic (acoustic) full wave form records,such as the traveltime acquisition of initial wave.The paper also discusses the establishment of neuron network model and the study of neuron network model,with an emphasis on the characteristics of the initial wave when it appears.Aquantitative description is given,and its application to the information collection of seismic (acoustic) full wave form records has exhibited very high precision.

On the basis of the theory of diffusion and convection of radon, the predent paper has formulated migration equations in arbitary media as well as in rock and soil near the surface, and set up a model for ground atmosphere exchange of radon.The migration regularity of radon in media has been studied and the theoretical equations verifield by model experimentation. The authors used the theoretical model to calculate the radon concentration of air at a certain residential area of Linchuan City, Jianxi Province, which has been preliminarily proved to the effective.