This paper gives a comprehensive description of new advances in the development of aerogeophysical techniques used abroad and describes such instruments as aeromagnetometer and UAV,gamma spectrometer, and the newest aeromagnetic, aeroelectromagnetic and airborne gravity surveying systems as well as the data-processing software.

Geophysical methods play a very important role in geothermal exploration of Beijing area. With some practical exploration examples, this paper has summed up the geophysical geothermal exploration methods used at present, evaluated the application effects of some new methods, and put forward the combinations of several integrated geophysical methods and the rational geothermal exploration procedures suitable to different geological and structural backgrounds for researchers' reference in practical exploration work.

The gold-silver ore-forming belt in Laowan is one of the gold-silver ore belts of metamorphic clastic rocks.Two large gold deposits were discovered in the Shangshanghe and Laowan area.Later,based on the new researches on the 1:200 000 geochemical data obtained from Laowan,the authors found that gold anomalies obviously exist along the northern part of the belt.Then,through the 1:25 000 survey of hydrographic sediments and the detailed 1:10 000 geochemical exploration, combined with the known geochemical and geophysical anomalies,the authors discovered that Xiemaling is the key target area for ore prospecting.This conclusion is based on the comprehensive study of known information of the mine and the selection of the goals.The local locating analysis and engineering verification of the ore-prospecting target has made new advances in ore-prospecting work.

Based on such means as utilizing the working methods and the principles of sequence stratigraphy,making the best of the formation correlation technique of high-resolution sequence stratigraphy,applying logging,drilling and seismic data,and choosing the isochronal boundary as the regional marker bed for stratigraphic correlation,the authors set up the uniform isochronal formation framework of C Formation in the G Oilfield of Syria.On such a basis,the authors used GR and density to invert the profile and make reservoir prediction.The distribution of the reservoir was detected through the study of the lithologic character.

The primary research methods in geology remain based on observation and experience. However, the logging data are of fine continuity and high resolution. The theoretical foundation of stratigraphic sequence identification consists of the complexity and relative consistency of sedimentary cycles, the continuous and nonperiodic characteristics of logging curves, and the multi-resolution and time-analysis characteristics of the wavelet transform. The Xujiahe logging data with the highest resolution and best continuity has been divided into three stratigraphic sequences and eighteen subsequences as a case study.

The continuation of the observed gravity anomaly on an undulate terrain to the mean horizontal plane is carried out.Then the gravity field on this plane is separated by cutting the method into several fields caused by strata at different depths.Gravity fields resulting from different strata are downward continued to the corresponding depths,and the density of the strata is inversed.The density obtained by this method is the approximate density contribution of the strata,and is called apparent density imagery.In downward continuation of the gravity field,a new continuation method,i.e.,iteration approach,is used.The process of continuation is stable and has a relatively great depth of continuation.This continuation technology does not need to solve linear algebraic equation system and can overcome the computation time bottleneck which hinders the application of 3D inversion to practice.For a data set of 71×81 points,it takes 10s for 3D inversion on a 1.73 GHz PC.A real case in a certain area of Xinjiang is presented to demonstrate the effect of applying this method to inversion.

Because of instability,the downward continuation,which is the core operator of the gravity interface inversion by using Parker-Oldenburg (PO) method,restricts the application of the method. This paper introduces a stable and high-precision downward continuation substituting for the intrinsic operator in the Parker formula. Satisfactory results were obtained in the inversion by using the synthetic model and in an application of the method to gravity anomaly over the Yinggehai Sea of the South China Sea.

Due to the self-transition of the loop, the early signal of TEM suffers great distortion. In order to study characteristics of the early signal with TEM, the authors formulated self-induction formulae for single coil and multi-turn coils, deduced theoretical expressions for the amplitude of the loop self-induction signal, and gave the induction of single coil and multi-axial coils. The response curve of buried object affected by the coils and the length of loop's change are also studied. The results obtained lay a foundation for further studies of the additional effect of the early field and can serve as reference data for further researches.

The Screen Electrode Method (SEM) is an electro-exploring method which can emphasize anomaly of the deep object and increase the detecting depth of the electro-exploring method through changing the distribution of the underground current density by the current compensate electrode. First of all, the distribution of the current density in the uniform half space is theoretically analyzed in this paper when the screen electrodes are arranged at the earth's surface. Then simulating calculation of profiles and soundings of the DC electro-exploring method are numerically carried out, supported by ANSYS that is a software based on the finite element analysis method. The calculation results show that the detecting depth of SEM is deeper than that of the common DC electro-exploring method when the locations of the screen electrode and the intensity of the compensate current are rationally selected. The theoretical analysis and simulating calculation show that the SEM can efficiently increase the detecting depth of the DC electro-exploring method.

Using four geochemical methods, i.e., radon measurement, accompanying element measurement, metallic active state survey and earth gaseous water uranium survey, the authors made a tentative test in a known ground-leached uranium deposit in northern China. The results show that the first two methods remain effective, the study of the third method should be further deepened, and the fourth method has gained certain advances.

At present, the researches on 2D inversion of IP data mainly aim at the HD (high density) IP data, which is mainly due to the equivalent distances between neighboring poles during data collection. Under such a condition, the division of finite element grid is convenient and the forward and inverse operation is easy. In forward operation, the finite element grid is automatically divided according to the practical data, and dual-grid system is used. The finite element modeling with linear variation of conductivity within each block is done, and the error of modeling result can be modified. In inversion, the partial derivatives of the apparent resistivity with respect to model resistivity are calculated by means of the relationship between the source and receiver locations and Broyden's method. And it is solved by using the conjugate gradient method, in which the calculation precision is almost the same as that in the SVD method. Through inversing the modeling data and observed data, it is shown that the algorithms of this paper are workable.

Geostatistical inversion (GI) combines the advantages of stochastic modeling and seismic inversion, integrates geological, logging and seismic data, and delineates the reservoir more preciously. Constrained sparse spike inversion is conducted to predict the general distribution of reservoirs before GI, and the results including wavelet and 3D acoustic impedance (AI) can be used later. The inversion uses both well-log and seismic data. The inter-well AI is created by stochastic simulation, and the subsequent work includes (1) simulating an AI at the interwell point, followed by computing reflectivity series, (2) convolving it with the wavelet selected to simulate a local trace, and (3) implementing iterations to make the simulated and seismic trace reach a desired fit. The results are of multi-equiprobable 3D AI volume realization, which can be used for uncertainty evaluation. The inversion integrates the high resolution of logging and lateral directions of the seismic data. The results fit the geostatistical features of the input data, and are constrained by structural and stratigraphic earth models.

Based on time-varying resistivity expression of Cole-Cole model in time-domain and apparent parameter formula of time-domain induced polarization and using digital filtering and equivalent resistivity method, the authors have developed the iterative finite element simulation of time-domain induced polarization spectra. This program can simulate characteristics of induced polarization anomalies of various geologic bodies under different wall rock conditions. The results are in the form of data files and plot files. It can provide large quantities of information for studying the induced polarization method.

The automation of the measurement adjustment is the aim of the surveyors. Many countries have designed softwares, but the softwares have some disadvantages. This paper introduces a new way to design a measurement adjustment system on the basis of the study of the merits and shortcomings of the previous programs. The system based on VC++ and ObjectARX and AutoCAD2000 has its power roof garden. The system can calculate coordinate exactitude value and draw the net shape. The operation is very easy and hence it can serve as the surveyor's effective helper.

Recently, TSP has been used widely in China. But we do not know the data format because the manufacturer does not provide it. With an application example, the authors studied the TSP data files by UltraEdit software, and got to know their construction. Furthermore, the authors introduced SEG-2 format simply, and wrote corresponding routines for reading the SEG-2 data and TSP files in Matlab programming language. On such a basis, we can translate a SEG-2 file into a TSP file and process it by the TSPwin software.

Some main problems existent in the present standard for farm products areas of China are discussed in this paper. It is thought that the formulation of a nationwide environment standard for producing areas is not only technically difficult but also likely to give rise to lots of troubles in the course of practical application. Based on the 1:250,000 survey of earth geochemistry of the agro-geological environment in Zhejiang and the study of such affecting factors as the geochemical composition, content and distribution of elements and taking into account the effective quantities of elements that affect people and environment, the authors have formulated the standard of earth environment quality for the unpolluted farm products area in Zhejiang for recommendation. Although there are many factors that affect the quality of farm products, such as atmospheric fallen dusts, irrigative water and fertilizer application, the quality of earth environment in the farm products area obviously plays the most important role.

Based on an analysis of groundwater pollution situation,the harmful result,causes and the pollution channels,the authors put forward a series of countermeasures,such as the tackling of "three wastes",the restriction and suspension of exploitation,the layering exploitation and the drawing of water as well as the replenishing of the sources.

The root system selenium has relationship not only with the amount of selenium, but also with the acidity and alkalinity of soil. The amount of selenium in surface paddy is lower than that in the root system.The amount of selenium in leaves is lower than that in root but higher than in trunk, with the fringe part having the lowest selenium.42%～50% of selenium in the plant at surface earth is in the fringe, and only 2.31%～4.31% of selenium is in the plant. Moreover, the amount of selenium in unpolished rice is lower than that in paddy but higher than that in rice. There is a direct proportion between the amount of selenium in paddy and the acidity and alkalinity of soil, which means the stronger the alkali in soil is, the higher the amount of selenium in paddy becomes. The amount of selenium in the body of paddy has something to do with that in the paddy soil, which means that there exists a direct proportion between the amount of selenium in soil and that in paddy.

Exemplified by the Xuefengshan Highway tunnel characterized by extraordinary length,large buried depth and complex mountain conditions, this paper has described and analyzed such technologies as the high-resolution seismic shooting technique, the high-resolution multifold coverage technique with common spread, bi-direction and variable offset for complex topography and geological structure, and the synchronous construction technique of seismic reflection and refraction for environmental protection. All these technologies have been developed and applied in practice according to field conditions.

The 3D directional borehole radar system can perform 3D mapping for the surroundings of a borehole with high resolution. The detection of the distance from the borehole and the angle in relation to the magnetic North can be completed in a single borehole. The system has many advantages over the 2D borehole radar in such aspects as high resolution, rapidness and great penetrating depth. The authors deal with the working and imaging principles and technical specifications of the 3D directional borehole radar in details and, combined with field data, show its true application results.

Initial attempts to subdivide the offshore succession in Hong Kong waters were made from the description of sediments in boreholes. Subsequently, more exact work refined this scheme by using the results of detailed borehole analyses, the interpretation of seismic records and, more recently, the sequence stratigraphy. Making use of three instances, this paper deals with the application of high resolution single channel reflection marine seism in this field in detail. Field data acquisition and techniques for suppressing noise in shallow waters have also been discussed in brief.