Comprehensive utilization of mine tailings is an effective method for solving the problem of coordination between resources and environment. Based on analyzing potential resource value and environment effect of mine tailings, this paper points out the necessity and importance of nationwide geochemical survey of mine tailings for tailing comprehensive utilization, describes the ideas and methods of nationwide geochemical survey of mine tailings and forecasts the application prospect of data and achievements obtained in this survey.

The geophysical ore-prospecting model of the Huimin iron deposit was established on the basis of studying the characteristics of gravity and magnetic field of the Huimin iron deposit at three different levels. Combined with the proven bore hole data and the parameters of the ores, the authors got the resource quantity of C1 and C2 magnetic anomalies along No. 76 exploration line by using magnetic anomaly to fit the volume of iron ore body. The resource quantity of other magnetic anomalies was also obtained by analogy. A comparison with the proven resource shows that there exists some potential in search for iron ore bodies in this area.

Regarding host rocks and magmatic rocks as a whole system connected by ore fluid activity, the authors systematically investigated the REE behaviors of magmatic rocks, host-rocks and skarns influenced by ore-bearing fluid in the Handagai skarn-type Fe-Cu mineralization area. The REE compositions of Fe-Cu ores imply that they were derived from the contact metasomatism and the ore-forming hydrothermal fluid had relatively high temperature. The authors infer that the ore fluids should be characterized by ∑REE depletion and relative enrichment of ∑HREE and Ce. Results of the study indicate that the application of REE geochemistry to mineral prospecting has great potential.

Based on applying valley soil geochemical survey to ore prospecting in the Jiucaigou ore district, the authors found some valuable anomalies. Combined with ore-controlling factors such as strata, lithologic character and structure, the authors analyzed the prospecting potentiality of element geochemical anomalies of Au, Ag, As, Hg and Sb. Element anomalies of As, Hg and Sb can indicate gold mineralization. The prospecting direction was pointed out, and three key targets for ore-exploration were delineated. Later, every key target was verified by exploration and surface work. Ideal ore-prospecting results were achieved. This method has been proved to be effective in geological prospecting and exploration, which provides scientific evidence for further work.

Integrated geophysical methods composed of AMT and high resolution magnetic survey were used to the exploration of hard rock-type uranium deposits in Baimianshi area of southern China. The results show that some deep geological structures such as buried depth of volcanic basin basement, fault structure and volcanic apparatus could be well detected by using the integrated methods and on the basis of sharing their complementary advantages. Effective technological measures are provided to the exploration of deep buried uranium ore bodies in the hard rock-type uranium deposit of southern China and the outskirt extension of the ore deposit.

This paper describes the basic principles and characteristics of the wider field electromagnetic method and the definition of apparent resistivity of the wider field. Exploration work was carried out in a silver, lead and zinc ore deposit of Inner Mongolia, including the deduction and interpretation of the anomaly. The result compared with CSAMT shows that the wider field electromagnetic method can achieve a larger exploration depth as well as higher exploration efficiency and precision with a smaller distance between transmitting and receiving. Hence the method has obvious effect in search for deep metallic ore deposits.

Located in the north-central part of Laos, the work area is covered by rainforest and adjacent to the intersection between NW-trending Truong Son magma-tectonic belt and NE-trending Louangphabang magma-tectonic belt. In order to survey the copper polymetallic resources of this work area, the authors employed high-precision geomagnetic method and IP intermediate gradient respectively, and the results show that most geophysical anomalies correspond to the distribution of skarn mineralized bodies in the contact zone between granite and carbonate rock. A comparison of high-precision geomagnetic method with IP intermediate gradient shows that the exploration effect of high-precision geomagnetic method with lower cost and simple operation is better than that of IP intermediate gradient in rainforest landscape areas.

Geothermal fields in Gui'an of Fujian Province are mainly controlled by faults. Using one-dimensional inversion results and CSAMT method, the authors simulated the spring when the upwelling spring water surface was distributed at different depths to study the distribution pattern of the faults, and found the spatial distribution of faults and the relationship between various faults in the study area, and the effectiveness of the result was proved by drilling. The result shows that this means is effective in looking for fault structure.

This paper reports the water exploration result of the EH4 electromagnetic system. Following the principle of "from known to unknown", the authors arranged the geophysical exploration work closely in combination with geological data, obtained complete geophysical data and made fairly reasonable interpretation, thus attaining quite satisfactory water prospecting result.

Shallow crust metallogenic mechanism is closely related to different types of deep-seated structures. The Moho can well indicate the deep tectonic characteristics. This paper deals with the relationship between the Moho and the ore concentration areas through reconstruction of the Moho based on regional gravity data obtained in Hebei Province. Large-size gold, lead-zinc and other ore deposits are existent in the mantle slope zone; polymetallic and sedimentary ore deposits occur in the mantle-terrace area, with the sizes being smaller than those in the mantle slope zone; large-size coal, oil and some other sedimentary ore deposits are abundant in the mantle uplift zone; lead, zinc and other polymetallic ore deposits are abundant in the mantle depression zone.

Daolang and Duge area is a polymetallic ore-forming belt on the northern margin of the North China Plate. In order to forecast polymetallic distribution in this area, the authors employed such means as upward continuation, small subdomain filtering of the first vertical derivative and corresponding analysis of gravity and magnetic anomalies to process the 1∶5 000 gravity and magnetic data. Characteristics of gravity and magnetic fields, residual gravity field, the first vertical derivative of gravity anomaly, correlation coefficient R of gravity and magnetic corresponding analysis and their relationship with the density and magnetic susceptibility of rocks and minerals were analyzed comprehensively. Combined with the regional geology and drilling data in this area, the authors delineated 5 faults,11 ore-forming prospect areas, and analyzed the basis for delineation of faults and prospect areas comprehensively.

Based on data processing of 1∶25 000 stream sediment survey in Hongshishan area, the authors delineated anomalies of such elements as W, Sn, Bi, Au, As, Sb, Cu, Pb and Zn, revealed distribution characteristics of anomalies in this area, evaluated prospecting significance of the anomalies, and determined element associations. According to characteristics of composite anomalies and element associations in combination with ore-forming geological setting, three ore-search prospective areas of W, Au and Cu were delineated, of which the optimized No.1 composite anomaly seems to be the best ore-prospecting target area for W and Au.

In the piedmont zone of the Saishiteng Mountain on the northern margin of Qaidam Basin, the thrust-nappe structure is developed, the surface condition is poor and hence the seismic prospecting is difficult. As CEMP method is hardly affected by the shielding effect of overthrust nappe structure and the effect of surface condition, the authors conducted researches on CEMP exploration in this area. In this paper, several methods such as Robust, remote reference technique and static correction were adopted in data preprocessing to suppress noise and improve data quality. Through the comprehensive utilization of Bostick, CMI and 2D continuous medium inversion, the effective anomaly was detected obviously, the structural characteristics of overthrust nappe was unveiled clearly, and the spatial spread of lower wall strata around the thrust-nappe fault and the contact relation between the mountain and the basin were determined in this area.

This paper deals with the improvement of the calculation accuracy of derivation in the frequency domain and studies the stability and accuracy of the local wavenumber inversion result. A comparison of the calculation accuracy between the cosine function extending edge and the minimum curvature extending edge shows that the result of minimum curvature extending edge is higher than that of the cosine function extending edge. This paper proposes a technique which uses upward continuation to a certain height to acquire the local wavenumber inversion, which solves the high-frequency interference, improves the calculation accuracy of the derivation, and also obtains stationary inversion results that use different continuation heights, thus improving the accuracy of local wavenumber stationary. The precision of the technique was tested with numerical models. The authors have attained satisfactory results, as evidenced by the fact that the stabilization of the technique was proved by the real data processing.

Currently, the static correction method widely used in the production is almost always based on surface-consistent hypothesis. However, in complex areas with sharp fluctuant topography and great low velocity layer thickness and transverse velocity change, the surface-consistent hypothesis is sometimes unfit for actual geological conditions; in this case, there must be significant errors if surface consistency static correction is still used. Modeling methods are used in this paper to discuss the cause for surface-consistent hypothesis static errors in complex areas and the relationship of this cause to datum, source-receiver offset, low velocity layer, bedrock speed, low-speed thickness and reflective surfaces depth, with an analysis of the variation regularity, in order to improve the existing static correction method, present a new approach and provide the reference for solving the problem of static correction in complex areas.

The essence of the residual static correction is a nonlinear optimization problem, so the overall optimized algorithm can be used to deal with this problem. A hybrid optimization inversion method is developed to calculate residual static correction by integrating stimulated annealing and genetic algorithms. The application of this method to synthetic and real seismic data shows this method is adaptable and effective.

This paper proposes a new ray-tracing method based on the concept of simulated annealing. With the new method, not only the problem that the traditional ray-tracing method is over dependent on pre-established initial ray-paths is well solved, but also the quality of desirable ray-paths construction and the associated traveltime calculation between fixed sources and receivers is ensured, even if the model is of much complicated velocity-field. As a result, the ray-paths whose traveltime approach is overall minimum are searched out successfully. Furthermore, the algorithm may calculate ray-paths with local extreme lower traveltime too and restrict them easily by instructing rays to pass through some fixed points. The feasibility and stability of the method have been proved by trial results of theoretical models.

Based on reviewing the development of prestack depth migration, this paper has summed up several current prestack depth migration techniques, i.e., Kirchhoff integration, wave equation, and reverse-time migration. On the basis of analyzing the prestack depth migration imaging method in such aspects as wavefield, applicability, sensitivity of the near-surface condition and existing problems, the authors made a comparative study of different migration imaging results by comparing the migration sections, indicated the development orientation of the prestack depth migration and put forward some proposals for further study of prestack depth migration.

The delta-front of a certain area is characterized by fast facies change, strong heterogeneity, and small thickness of a single sand body. As the earthquake-band of the conventional deterministic inversion is limited, the vertical resolution of the seismic inversion body is very low, and hence it is often difficult to identify the small sand body. The geostatistic inversion method based on stochastic modeling technique can effectively integrate geological, logging and seismic data, greatly improve the seismic vertical resolution, and more accurately describe the subtle changes in the reservoir, thus well identifying the thin sand. Geostatistic Inversion was used in delta-front of a target area to predict the thin sand layers. The impedance body derived from the high-resolution geostatistic inversion method was compared with the density body, which could effectively identify a thin layer of sand body in the horizontal distribution on the inversion profile. This method provides a basis for identifying favorable oil and gas traps.

Based on the GDP32 multi-function electric apparatus produced by Zonge Company and its application software, this paper discussed some problems concerning the practical application of CSAMT and proposed the criteria for judging the data. With practical examples, this paper discussed some correction methods of static effects, summarized the merits, demerits and applicability of one-dimensional inversion and 2D inversion. It is held that the color gradation of the resultant map can be adjusted according to different work aims and that suitable numerical processing can be made for resistivity. In the end, the author investigated the interpretation depth of CSAMT and dealt with the feasibility of confirming boundary by use of drilling data.

With the broadband signal, weak signal energy and small magnitude in comparison with the tradition MT, the long-period magnetotelluric survey has a higher data processing requirement. In this paper, the Robust algorithm based on repeated median estimator was applied to long-period magnetotelluric impedance tensor estimates. Compared with the Robust maximum likelihood estimate (M estimate), the repeated median estimator has no need of reset parameters in data processing, and can increase the estimate of the breakdown point up to 50% and get an unbiased estimate of impedance tensor. An application example shows that the Robust algorithm based on repeated median estimator has a strong advantage in the solution of the impedance tensor.

This paper describes in brief the principle and field work methods of the FD-3017RaA radon measuring instrument. An analysis of ore-bearing profiles in different kinds of typical ore deposits shows that, over the fault shatter zone, the major peak of the radon anomaly reflects the surface exposure location of the structural shatter zone. It is thus concluded that the application of radon measurement to the prospecting for concealed fractures is very effective, and that radon measurement can be especially used as an auxiliary means in search for concealed ore deposits closely related to fracture structures such as faults, joints and cleavages.

With engineering examples, this paper describes the application of the ultra-high density resistivity to the investigation of karst caves and fracture zones, summarized the points for attention during the data acquisition, and made a comparison between the achievements obtained and the drilling data. The results show that this method is fairly effective in detection of the distribution, sizes, buried depths and development of karst caves and fracture zones, and can thus serve as a geophysical method for improving the precision of engineering exploration.

Based on the method of SY/T 6009.1-2003, the authors studied the analytical method for acidolysis hydrocarbons in marine sediments. Its accuracy, precision, detection limit, reproducibilities of different laboratories and the effect of storage time were discussed in detail. The method provides the advantages of usability and reliability, and can meet the requirement of determination of acidolysis hydrocarbons in marine sediments.

Surface soil in the growing area of Fengjie navel orange was collected for analysis, and geochemical characteristics of major elements and main trace elements as well as their effective state were investigated. The content of main nutrient indices N, P and Corg is relatively high, while K content is ordinary. In trace elements, Fe, Zn and B are of relatively even distribution, Mn and Mo are somewhat unevenly distributed, and Cu is very unevenly distributed. As for soil element effective state, effective P, Mn, Cu, Si, K and Fe are abundant.

Based on statistics and analysis of eight heavy metal elements in near-surface atmospheric dustfall of Tangshan, the authors found the existence of obvious differences and the uneven distribution of heavy metal pollution. Based on the Kriging interpolation analysis of the eight heavy metal elements in near-surface atmospheric dustfall, the authors have reached the conlcusion that the distribution features of the eight kinds of metals have a somewhat identical high value in this area, with the South Lake park as the center. This anomaly area extends northeast and northwest. Based on principle component analysis, it is held that the heavy metals in near-surface atmospheric dustfall of Tangshan are mainly attributed to coal and traffic sources. The results obtained provide basic information for the understanding of the air quality and atmospheric environment pollution in Tangshan City and the performance of urban planning.

This paper reviewed the key features of non-seismic exploration domain software developed by oil companies and mining companies in such foreign countries as Canada, Australia, the United States and Britain as well as by research institutes, colleges and universities and geological exploration units in China. On the basis of a comparative analysis of the Geosoft's Oasis montaj and AGRS's software like AirProbe, the authors hold that the development direction of non-seismic geophysical software is integration, platformization, parallelization, visualization and internationalization.

The T₂ spectrum inversion from NMR data has been widely used in petroleum industry both in core analysis for petrophysical studies and in logging interpretation. In order to improve and consummate algorism of inversion, the authors used the NMR numerical simulation data to study the factors influencing T₂ spectrum inversion from NMR data, such as the intervals and number of echos, and signal-to-noise ratios. The method of T₂ spectrum inversion was compared with optimization algorithm and singular value decomposition (SVD) at different signal-to-noise ratios at the same time. The result shows that TE should match the number of echos and components to attain the best inverse effect when the NMR relaxation signal is collected. Higher signal-to-noise ratio can reach better effect, and when the signal-to-noise ratio is larger than 25, the inverted spectrum coincides with designed spectrum. The method of T₂ spectrum inversion with optimization algorithm doesn't require high signa-to-noise ratio, and the method of SVD could clip inversion.

In data processing of anomaly separation, the structure method of trend surface adopts the fitting of a polynomial. It has some shortcomings, for example, the degree of fitting cannot be adjusted and can even show distortion. This paper proposed the construction method of trend surface based on the wavelet transformation. This method can extract the information effectively from the signal. The approximate coefficient obtained after the wavelet transformation characterizes signal tendency, and approximate coefficients of different criteria represent tendencies of different criteria. The coefficient and the detail coefficient of the static wavelet do not experience low sampling, so they have the same length as the original signal. The method can construct trend surfaces of different fitting degrees according to the requirement and is of distortion degree.

The porosity of gas coal samples was tested. On such a basis, this paper deals with the relationship between the elastic anisotropic coefficients and the porosity of the gas coal samples, and the result shows that the value of anisotropic coefficient is to a certain extent related to porosity. This paper simulates the one-order stress-velocity equation with the staggered grid high-order difference method, and analyses the stability and boundary conditions. The simulations of Thomsen show that, in the wave simulation with the staggered-grid high-order difference method,ε denotes the anisotropic degree of of P-wave,and δ is the changing degree of transverse and vertical anisotropy of P-wave. The result is of important significance for studying the anisotropy of a coal field.

On the basis of In-depth study of the structure of SEGY seismic data files and the coding of IBM PC workstation platforms, this paper tracked the whole process of code exchange of the seismic data from SEGY format to the IBM PC workstation, found and solved the precision loss of the transformation, ensured the accuracy of transformation of seismic data, and paved the way for accuracy of further seismic data processing.

Based on a brief description of the basic principles of the time domain Radon transformation and inverse Radon transform, this paper studies the application of this technology to seismic data processing. Based on the algorithm designed by Ng and Perz in 2004 and the problems encountered in the seismic processing and interpretation system, this paper resolves the accuracy regarding the convergence precision of the time domain Radon transformation, the demand of non-destructive reduction, the energy spread problem caused by truncated signal and the signal's filtering problem under low S/N, and gives the applications of the improved algorithm in other terrains for further research.