Being a new branch of sciences, geochemical engineering has the following basic characteristics: with the systematology as the guidance, the environmental problem and its harnessing and protection are considered in the natural geochemical system; on the basis of geochemical principle and regularity, the properties of the discarded substance and the discarded natural materials are fully utilized to develop the salvage technology; technological designing is combined with natural conditions and natural geochemical actions so as to reduce the cost and raise the benefit. The improvement and popularization of the geochemical engineering in the direction of industrialization should gain the vigorous support from the government and the industrial circle.

The Yindongpo gold deposit is one of the important large size gold deposits in China. Based on an analysis of the regional geophysical field, the physical character parameters and local anomalies, this paper has established geophysical ore prospecting criteria and combinations of methods in different working stages so as to improve the researches and raise the efficiency of geological ore prospecting work.

With some practical examples, this paper has summed up the effectiveness of IP method in the exploration of underground water and the water-searching regularity in the army water supply.

It is quite difficult to perform coalfield seismic exploration in thick-loess covered hill areas because of the loose loess structure, strong absorbency to seismic wave and deep water table in these areas. In Jie-Ping areas, the Shaaxi Geological Research Party for Coal Exploration adopted a series of data acquiring methods and low signal-to-noise ratio data processing technique to solve these problems on the basis of deepgoing researches. The technique has been proved to be effective and can be used in other similar areas.

This paper describes geochemical characteristics of the Reshui gold deposit in Inner Mongolia. The formation of this deposit is closely related to the diorite dyke. Ba, As, Sb and Hg in the ore vein are upper elements, whereas Co, Ni and Mo are lower elements. Gouxishan ore vein group is estimated to have been denuded, with only the tail part left. Tangfanggoudongshan has fairly good ore forming geological conditions, its denudation is not so strong as that of the main ore district, and its soil mercury anomaly is quite obvious; therefore, it should have fairly promising metallogenic prospects.

Based on a study of the techniques for 1:50000 stream sediment survey in forest swamp frozen soil landscape area of northern Da Hinggan Mountains, the authors have discovered that the adoption of relatively coarse grained fragments (-10～+60 mesh) in stream sediments can effectively eliminate the interference of organic matter and strengthen the anomaly. It is also held that in areas where stream sediments are not well developed, the utilization of stream sediment survey with the help of grid soil survey can obviously raise the ore prospecting efficiency.

This paper deals with characteristics of the Ag, W, As, Sn, Au, Pb, F, Cu and Zn composite anomalies in the Yaogangxian orefield centered on the Wore district and, on the basis of an analysis of the geological setting of the orefield, points out the favorable silver-search prospects in the orefield.

5000 soil samples from Yanchuan area of Shaanxi Province were analyzed by fluorescence photometry and ultraviolet spectrometry. The experimental conditions were investigated. By utilizing integrated mode in fluorescence photometry and flow injection sampling method in ultraviolet spectrometry, this method can use less reagent and attain better reproduction.

This paper describes an improved method for geochemical multi element anomaly taxis. Compared with the traditional method, the new method can reduce the influence of the denudation extent, and therefore yield more reasonable result.

This paper describes the evidence weighting method and its theoretical basis. Based on the metallogenic theory of interlayer oxidation zone sandstone uranium deposits and applying information system software for exploration of sandstone uranium deposits which was formed by secondary development of ArcView3.2, the authors extracted ore controlling information from Klulun basin, analyzed integrated evidence factors through evidence weight, and finally completed prospective prognosis of the interlayer oxidation zone within the basin.

Since there exists a distinct wave impedance surface between the cover and the medium-to-weak weathered rock, most energy of the incident wave was restrained in the cover and it is very difficult to stimulate effective elastic wave in the rock. Therefore, the response signal of the cavern or fault in the rock was too weak to record. Simplifying this kind of structure by two layer model together with the analysis and calculation of the wave equation, we can find the penetration laws of the incident energy on rock surface and then theoretically show that it is possible to choose little offset and near critical angle SVwave measuring in shallow or ultra shallow seismic survey. The consideration of as many factors as possible can lead to good ideas with which we can stimulate the most distinct response signal of the concealed targets.

To investigate the influence of transmission attenuation of seismic waves in a layer cake model, the authors formulated a seismic convolution model by considering the coefficient of transmission attenuation, and then provided a new forward algorithm for the model based seismic inversion of impedance. Seismic data processing practices demonstrate that the seismic convolution model can be used to correct transmission attenuation component by means of impedance inversion, with the merit of avoiding the screen effect of strata. Therefore, the authors believe that the seismic convolution model proposed in the paper is useful in the impedance inversion of seismic data.

According to the theory of dual frequency IPmethod and the technical requirements for the dual frequency IPinstrument, the authors have analyzed the principle of the SQseries dual frequency IPinstrument designed and made by ourselves, and described the hardware, software and specification of this IPinstrument. Its field application shows its high reliability and quality, as evidenced by the satisfactory geological effects achieved.

Based on probing into some factors affecting the adsorption quantity in the adsorption filament method, the authors hold that the blackness and the humidity of the activated charcoal have considerable effects on the adsorption quantity, and that moisture seems to be the main factor affecting the adsorption quantity. Therefore, only when the activated charcoal with certain blackness is used and the tested samples are relatively dry can better result be attained.

The attitudes of stratum obtained directly from imaging logging images are apparent values, and are related to the logging tool coordinate system. For the case of tilted borehole, deviation correction for the attitude values should be executed. In this paper, an algorithm is presented to correct the attitude values derived from imaging logging with borehole deviation data. As a practical example, the approach is applied to imaging logging data processing of the second pre pilot drillhole of Chinese Continental Scientific Drilling in North Jiangsu Province.

Starting with the traditional gravity topographic correction technique, the author completed Windows programming by using Delphi language, thus making it possible for computer to perform the gravity intermediate area topographic correction which had to be completed by manual calculation in the past and hence evidently raising the calculation precision. 53 gravity measuring points in1:200000 Changma sheet of Gansu Province were used to perform tentative calculation.

The values of analytical continuation at different depths from the potential field downward constitute the continuation field, on which the principal component analysis is made. The theoretical model calculation shows that, under the condition without any priori information, the energy weight value resolved from the continuation field or the maximum characteristic value of the matrix related to the continuation field can be used to judge the position of the potential field source, thus determining the burial depth of the geological body. Such organic combination of the determined signal analytical method for potential field analytical continuation with the stochastic signal analytical method for principal component analysis provides a new channel for the inversion of geophysical potential field.

This paper describes the utilization of VBto write an applied program and form a plain code file which has a certain data format recognizable by MAPGIS, with the purpose of using MAPGISto make the picture frame suitable for the professional characteristics of one's own unit.

In the near zone apparent resistivity formula of central loop and coincident loop in layered ground, the power n of time delay t was formerly regarded as a constant. In fact, it is a variable. This paper has proved through inference that its Δn-value is equivalent to the logarithmic difference of apparent longitudinal conductances. Therefore it can be used to interpret the direct division of strata. For this purpose, the authors made quite a lot of mathematical model calculations, and the result shows that under certain circumstances the strata can be rather satisfactorily divided; nevertheless, the observation precision should be very high.

Aimed at solving the low accuracy problem in high strain dynamic pile testing method for toe bearing tubal pile testing, the authors, based on years of actual testing experience, put forward the essentials for testing and the analyzing and interpreting method of the toe bearing pile in the soil, which are of practical guiding significance. These opinions are formed through summing up various stress bearing characteristics and actual curve features of this kind of piles and carrying out comparative sorting and analyzing study.

Based on the measured data of more than 100 deep stirring piles in a certain project, combined with static loading test on over 20 piles, this paper deals with the feasibility of using the reflection wave method to detect the completeness of the deep stirring pile body.