The authors summarized the basis and foundation of the prospecting prognostic method based on structural superimposed halo of the metallogenic belt. With the Rushan gold metallogenic belt in Shandong as the demonstration prognostic area, the authors put forward the new train of thought,working contents and flow chart for metallogenic prognosis based on structure superimposed halo in the metallogenic belt. The successful prediction results of Rushan show that the structure superimposed halo prediction is a direct, fast and effective way in regional metallogenic prognosis.

In order to carry out pre-investigation in the depth and the periphery of the Liushanyan Cu-Zn deposit in Tongbai County of Henan Province, the author studied characteristics of geochemical anomaly and evaluation criteria of this deposit. The major anomaly combination of elements is composed of Cu, Zn, Pb, Ag, Ba and Mo, (Cd), followed by Mn, Bi, As, Ga, Ge, V and W. Axial zoning sequence (from top to bottom) is Cu-Zn-As-Ga-Ag-Pb-Mo. Based on the characteristics of ore-related and barren anomalies, combination and zoning of elements, and elemental ratios, the author established criteria or indicators of geochemical prospecting.

In order to overcome the difficulties and make breakthrough in finding hidden deposits in the basin area, the author chose Zhouan ore deposit of Henan Province as the study object. The demonstration study in the known areas revealed clear anomalies of Cu, Ni, Co and obvious soil ionic conductivity directly above the known ore body. Two kinds of geoelectrochemical characteristics were observed in the basin area: On both sides of the concealed ore body, there exist element anomalies of certain sizes, and the middle section of anomalies on both sides indicates the location of the ore body. Above the ore body, the anomalies of soil ionic conductivity are mainly negative, and symmetrical peaks often appear on both sides of the ore body. In addition, the anomalies of Hg mainly assume high and single peaks and are distributed in the form of discontinuous jumps on profile. On such a basis, the authors set up an ideal geoelectrochemical prospecting model for nickel-copper deposits in Nanyang basin of Henan Province. In addition, the prognostic study was conducted in the peripheral zone, with three favorable targets delineated.

Field gamma ray spectrometry, as a method of geophysical exploration, is tentatively used to look for fluorite deposits in the buried and the half buried areas. Profile measuring of the Saiboluogoumen fluorite deposit in Linxi area of Inner Mongolia and analyzing the effectiveness of gamma ray spectrometry measurements in the prospecting for fluorite deposits revealed significant abnormal low radioactive values in the study area. The authors also analyzed the abnormal reaction under different geological conditions, and the results prove that gamma ray spectrometry is an efficient and fast means in prospecting for fluorite deposits in half-covered coverage areas.

A number of problems are discussed in this paper concerning the determination and interpretation of the oil and gas geochemical anomalies. It is emphatically pointed out that the characteristics of the statistical distribution and spatial distribution of geochemical data should be fully understood when the oil and gas geochemical anomalies are determined, and appropriate methods should be adopted to determine anomalies. The interpretation and evaluation of the oil and gas geochemical anomalies should be combined with the basic geological data, and systematic train of thought and methods of evaluation ought to used to reveal the link between the geochemical anomalies and hydrocarbon distribution.

Based on the data obtained from the scale 1:500 000 geochemical exploration, this paper deals with the laws governing geochemical distribution of metallogenic elements in east Kunlun region,and discusses the key elements related to gold deposits such as Au, Cu, Pb, Zn, Ag, As, Sb and Hg. This paper provided the elements spatial-temporal distribution regularity of dispersion or accumulation based on the geochemical characteristics of the elements so as to lay the geochemical theoretical foundation for the prospecting of regional gold mineralization. The gold target areas for exploration in near future were delineated, which included 3 GradeⅠareas, 6 GradeⅡ areas and 7 Grade Ⅲ areas,on the basis of the two typical gold deposit models for filtering and evaluation by GIS technology.

IP is an important method for mineral resources exploration, but it can only be applied in a few pivotal places because its difficult performance, and hence the information obtained from the survey area is very limited. The aim of this study is to find a simple and effective IP method with which we can get much valuable information form the survey area so as to improve the exploration effect. In the Yinan gold ore district, the authors applied the gradient sounding profile method, calculated 2D resistivity and obtained the IP model. The results show that the gradient sounding profile method is simple and effective.

The method of remote sensing interpretation was used to study regional geology and tectonic setting of controlled heat in this paper. A variety of geophysical prospecting methods such as CSAMT (Controlled Source Audio-frequency Magnetotellurics), DCS (Direct Current Sounding), medium gradient survey and measuring of combined profile were employed to reduce the risk of geothermal resource exploration and find the structure of the concealed fault zone. The results provide the basis for drilling and prove the effectiveness of these methods in geothermal resource exploration in Qinghai.

Beneficial and disadvantageous conditions are analyzed for the geological exploration of old mine's depth and edge with magnetic method. Based on some successful applications of magnetic method exploration in old mine' s depth and edge, the author made the following proposals: when metal minerals with magnetism are explored in old mine's depth and edge, the common, economical and effective methods are high-precision magnetic survey, aeromagnetic survey, magnetic logging and 3D quantitative inversion; the existing magnetic data should be fully utilized to make inference and interpretation; when magnetic body resulting in magnetic anomaly is explained, forward should be first used to get residual magnetic abnormality;the ore body resulting in residual magnetic anomaly in the depth and on the edge is inverted carefully to acquire the attitude and depth; the result of inversion is modified constantly by use of drilling data to enlarge the limits and scale of ore body in the depth or on the edge. The work method and steps mentioned above are helpful to exploration of metal minerals with magnetism in old mine' s depth and edge.

Some records were made for shallow geothermal temperatures of Guyuan and Raoyang in Hebei Province through test drilling, with the depth of the dill hole reaching 40 meters. the observation period lasted for more than one year and the authors recorded the data once a day. Based on previous work, the authors made an analysis of the hallow geothermal field characteristics and determined the relevant parameters of the stratosphere: the stratosphere depth at Guyuan is 24 m and the temperature is about 5.6 ℃, whereas the stratosphere depth at Raoyang is 18 meters and the temperature is 14.7 ℃ accordingly.

The gravity anomaly produced by rock in the strata will affect the reliability of the density interface inversion, so we should remove the influence before the calculation to increase the inversion reliability. In this paper, the authors used gravity and magnetic data in Tuquan basin to invert the rock and got the gravity produced by the rock with which we can perform the separation from the whole gravity field. 3D geological model was also established to reflect the spatial distribution of rock.

Through a comparison of AMT measurement between EH-4 and V8, the authors analyzed original data and inversion results of these two sets of devices in the same area, and made a comparative study of the performance parameters and work efficiencies of these two sets of devices. The results show that both V8 and EH-4 can collect real reliable data, V8 can collect lower frequency signal than EH-4,whereas EH-4 can collect higher high-quality frequency signal than V8. In addition, the continuity of data collected by V8 is better than that of data collected by EH-4, the efficiency of V8 is higher than that of EH-4, but EH-4 has the advantage of lower cost.

A method was designed for detecting trace helium, neon and hydrogen by means of gas chromatography. The detection of trace helium, neon and hydrogen was realized through back-blowing principle to protect the molecular sieve column. The analytical method established has the advantages of large measurement range, high sensitivity, short analysis time, long service life, and easy operation, thus having a good application prospect. This method was used to detect the non-hydrocarbon gases in the near-surface soil gases over Huangqiao helium reservoir, and the result proves its effectiveness.

There are stripe errors in airborne electromagnetic data, which impart data quality. To remove this kind of errors, the general method is to separate the true field values and noise combining various window filters. Presently, the challenge for this method is the selection of window parameters and the problem that the data processors need more trails and errors to get appropriate parameters. In addition, the processing period is comparatively long. The region control method is put forward in this paper. Utilizing 2D-DDL (data dependent nonlinear) filters, the method takes the entire gridded airborne electromagnetic data matrix as a window, and obtains the background of the whole region. As the control points of entire region, the background of the whole region is used to adjust the local background obtained by small window 2D-DDNL filtering, which is called automatic window parameter adjustment. As a result, the local background is adjusted to suit the control point of the entire region background. The differences between the backgrounds and raw data are middle variables composed of local geological anomalies and stripe errors. The adapted median filter is used to separate stripe errors, and the leveling results finally come out. This method can automatically adjust the size of window, reduce the human interference, and preserve useful geological information comparatively.

Some very important problems concerning the effects of airborne electromagnetic method are discussed in this paper, such as the selection of the surveyed area and the application mechanism of the frequency field airborne electromagnetic method. It is held that this method is suitable for such fields as the exploration of iron, copper polymetallic deposits and noble metal deposits, the underground water resource investigation, the land resource survey, the sea water invasion survey and the detection of water depth of the shallow sea and sea ice thickness, and the reconnaissance survey of low-resistivity nonmetallic deposits. The frequency field airborne electromagnetic has a wide range of applications. It characteristics such as low cost and high efficiency can be brought into full play as long as the surveyed area is properly selected and the work is reasonably arranged. And it will surely make its due contributions to national economic construction.

In order to understand the oil and gas exploration prospect in Mosuo-Wan field and reduce the exploration risk, the authors employed the KLinversion hydrocarbon detection technology and chose two important layers of pen 5 block for three-dimensional hydrocarbon detection. The testing results are well consistent with the actual drilling data, and the next step of target selection and risk prospecting is demonstrated.

Determining an accurate first arrival time of P wave and S wave is very important in locating microseismic events,and manual picking is extremely time-consuming and subjective.An automatic two-step method based on after-term average over before-term average ratio(ATA/BTA) and the Akaike Information criterion(AIC) is developed.The ATA/BTA is used to detect the event and the AIC is utilized for picking.The method can attenuate the impact of window length and improve the precision of picking.The examination of the algorithm in different window lengths and various SNR environments by using the real data proves its effectiveness and practicability.

This paper used staggered-grid high-order finite-difference scheme to simulate the propagation of source wavefield and reverse time propagation of receiver wavefield to finish elastic prestack reverse time migration in combination with energy flux density vector correlation imaging condition. The results of imaging for a two-layer model and a metal mine model prove that the scheme described in this paper can image the complex structure with steep reflector and eliminate artifacts in reverse time migration for elastic wave.

Based on analyzing the characteristics of borehole VSP observation system, the authors investigated the types and features of the observed seismic waves, analyzed ray-tracing and composite records of several VSP models (horizontal interface model, oblique interface model, meta-deviation distance model and detection point model), conducted forward modeling by using the ray-tracing method so as to obtain the forward result, and studied kinematic characteristics of the seismic wave. Some regularities have been detected: the number of the strata penetrated by the drill hole is equal to the number of intersecting points between the ascending waves and the descending waves in the composite record; there exist differences between the composite ray-tracing record obtained by utilizing P wave and that obtained by utilizing the transform wave, which shows that the transform wave has some influence on VSP composite record; strata of different dip angles have influence on travel-time features of ascending wave and descending wave as well as the energy characteristics of VSP; there exist reverse polarity phenomenon on the horizontal component of VSP composite record, which is consistent with the theoretical phase.

The inevitable temperature drift and time drift in the sensor, measuring circuit and amplifier of the electronic instruments will generate zero position error and gain error of instruments. So there exists obvious system errors in different instruments. The authors used two sets of Phoenix Company products which are V8 receivers in the Panlongfeng copper mine for TEM sounding. Because of system errors in these data,there are a lot of difficulties in data processing and appraisal of anomalies. In this paper, from the angle of numerical analysis, the authors corrected the system errors in different instruments by using the method of least squares curve fitting. The results show that the precision of correction is lower than 3%, and the ordinary precision of quality check should be lower than 10%. Hence the method of correction is effective and practical. In the Intel Visual Fortan developing platform, the authors achieved automatic correction of the system error.

The gamma spectrometer is developed in the digitized direction with the development of electronic technology and digital signal processing technology. In order to study and master the core technology of digital gamma spectrometer, the authors designed a gamma spectrometer based on digital pulse amplitude analyzer. This system consists of three parts, i.e., signal conditioning circuits, high-speed A/D acquisition card and digital signal processing program. The digital pulse analyzer based on high-speed capture card and digital signal processing program is crated to avoid building complex analogue circuits, and hence the flexibility and anti-interference capability of data-processing could be enhanced, and the pulse passing rate and actual measurement accuracy could also be improved.

In the quantitative study of the condensation water of Avalokitesvara statue in Dazu Rock Carvings, it is difficult to see and delineate the distribution area of the condensation water due to the adsorption of mantle rock regolith on sandstone sculpture. Therefore, according to the significant differences of infrared radiation characteristics between the condensate area and the surrounding area, the authors used infrared thermal imaging devices to detect the condensate zone of Avalokitesvara statue. The results show that the condensation water of Avalokitesvara statues is very serious. Even in the relatively dry winter and spring, the condensate zone takes up about 9.26% and 51.05% of the whole area. Meanwhile, the regional difference in the distribution of the condensation water is obvious, that is, condensation water in the lower left corner of the Avalokitesvara statue is the most abundant, and it gradually decreases from the bottom of the distribution area upward. Studies show that the infrared thermal imaging technology can accurately detect the area of the condensation water.

Through a comprehensive study of the results of dynamic monitoring exploration for seawater in Laizhou Bay by AMT method and other original data, the authors acquired further understanding of the present situation of seawater invasion inside the study-area. Moreover, the authors divided the interface zones between the salt and the fresh water, which resulted in favorable effects of environmental geology. The results indicate that the AMT(EH-4) method is effective in determining the interfaces between the salt and the fresh water, delineating the infection tunnel of seawater and observing the regularity of interface migration.

Though 1D inversion method is the most mature method in the TEM interpretation process, the inversion result fails to recognize both of the conductive layers in the inversion result of the two-layer model, with only a comprehensive conductive layer shown in the result. In order to separate two conducted layers whose resistivity and thickness are similar in 1D inversion TEM method, the authors successfully used the peeling method for the anomaly separation through supposing some assumptions and on the basis of the forward and inverse calculation of l theoretical model, thus obtaining the response after peeling the first conductive layer effect. The impact caused by the neglect of common reactance was studied with rougher assumption. The calculation results show that the conducted layer located beneath a conducted layer can be displayed in the 1D TEM peeling result.

Taking sequence stratigraphy division of K1y2+3 group in Yingtai-Da'an region of northern Songliao Basin as an example, the author analyzed the applicability of one-dimensional continuum wavelet conversion in high-resolution sequence stratigraphy division. Wavelet coefficient curves of different cycle orders can be obtained through Morlet wavelet analysis of GR curve, with whose conversion the logging data were expanded from depth space into-depth-scale space. Researches were conducted on the relationship between the periodicity oscillation characteristics of optimum scale wavelet coefficient curves and the boundaries of different level cycles, and the results were used to the identification and division of the boundaries of the sequence. It is shown that wavelet conversion is suitable for the division of mid-term base-level cycles and short-term base-level cycles, and it provides a new idea for the division of high-resolution sequence stratigraphy.

The alluvial fan is a common oil and gas reservoir with a significant seismic response characteristics.Using the frequency-wave number domain numerical simulation method,the authors performed a two-dimensional model simulation in two representative directions of the alluvial fan,and made use of the procedure of the combination of seismic forward simulation and the depth migration process to obtain the seismic response characteristics of the alluvial fan in two-dimensional time profile,thus providing a testing means for improving the correctness of the results of the alluvial fan geographic explanation.

Mudstone interlayer of Jintan rock salt gas storage constitutes a risk in cavity construction.How to identify the mudstone interlayer thus becomes a key problem in exploration.The mudstone interlayer distribution in this region is complex and the quality of seismic data is poor because of the influence of plasticity.As a result, it was hard to identify the mudstone interlayer accurately if only seismic data are used.Therefore,the features of seismic response and logging response of mudstone interlayer were analyzed,also the authors made a connection between gamma curves and seismic information,and carried out multi-parameters inversion.On such a basis,planar and special distribution features of mudstone interlayer were predicted.The application of practical data shows that multi-parameter lithologic seismic inversion can effectively reflect the features of mudstone interlayer variation.

There are salt domes of great thickness deposited in Pre-Caspian basin.As the salt layer thickness varies dramatically,it is difficult to perform imagery for the sub-salt seismic data,and the structure features show distortions.The elimination of the salt velocity influence and the restoration of the real sub-salt structure form constitute the urgent problems in oil-gas exploration.Through the integrated study of processing and interpretation,the authors used the floating datum pre-stack time migration method to conduct imagery for high and steep structures based on pre-stack fidelity of the static correction and to make salt amplitude recovery.Finally,the pre-stack reverse-time depth migration method was used for the sub-salt structure accurate imaging and recovery.A technological series of integration of processing and interpretation for sub-salt structure was formed and applied in Pre-Caspian salt basin.

Geo-statistical inversion method based on stochastic modeling techniques has high vertical resolution prediction results,but its results show high randomness.Therefore,reliability evaluation of the inversion results is very important.By using geo-statistics method and through setting up different inversion parameters,the authors compared the inversion results and,in combination with geological regularity,selected the optimal inversion parameters to predict thin bedded alternation sand body of SⅡ and SⅢ reservoir group in the development zone of northern Saertu oil field and analyzed the reliability of the inversion results qualitatively and quantitatively based on forward modeling.The results show that rational sampling rate of initial framework,reasonable well density of inversion,and variogram parameters in accord with geological conditions constitute necessary conditions for efficient inversion work and reliable inversion results.

In the area without logging curve,the reservoir prediction will encounter very great difficulty in seismic reservoir prediction.In order to solve this problem,the authors used stack migration data and seismic velocities of different incident angles in combination with genetic algorithm from pre-stack seismic waveform inversion of elastic parameters estimation to construct the virtual log curve.Practice shows that this means can solve the problem of getting the virtual logging curve in the area without drill holes and obtaining better result.With this method,more reliable virtual log data can be provided for seismic reservoir prediction.

Zhangqiang area,which belongs to Liaohe peripheral basins,is restricted by the influence of the surface conditions and underground geological structure,and hence data-processing has met with great difficulties.Lots of targeted measures have been taken in field acquisition, but part of the original data signal-to-noise ratio remains low,causing a certain impact on data processing.According to the characteristics of the original data for PSTM,the prestack data purification was conducted, and the accurate three-dimensional velocity field and the appropriate parameters were established to obtain a reasonable process flow.PSTM results show that the profile's breakpoint and fault are clear,and the homing of the diffracted wave was accurate.A comparison with the old data shows that the signal-to-noise ratio,resolution and deep imaging are improved significantly and can better reflect the structural form and stratigraphic architecture and meet the demand of the subsequent interpretation and inversion.

Clustering analysis and factor analysis were used to analyze stream sediment geochemical data sampled in Ranwu Sheet of Basu area, eastern Tibet, by using multivariate statistical methods. Four kinds of element combination type related to hydrothermal solution were selected, and the study region was divided into 20 geological subareas. In each geological subarea EDA (Exploratory Data Analysis ) was used to compute four kinds of element anomaly threshold. For element anomaly threshold Surfer was used for filtering and drawing element combination lining value anomaly map. Combined with the tectonic fracture characteristics, the authors compared the effects of the single element lining value and multielement contrast value. The results show that anomalies of mesothermal metallogenic elements such as silver, lead, zinc and cadmium are located between fault zones, whereas anomalies of low temperature hydrothermal ore-forming elements such as gold, arsenic, mercury and antimony are located in the fault zone. A comparison of copper lining value anomaly map with copper, molybdenum and tungsten, bismuth combination lining value anomaly map indicates that the multielement contrast value based on multivariate statistical methods is more effective in anomaly recognition in regional geochemical exploration.

In view of the difficulties in large-scale application of fitting local quasi-geoid surface to GPS height transformation in mountain areas, this paper puts forward an improved algorithm for GPS height transformation. The elevation abnormal difference equation based on gravity quasi-geoid geodetic height is transformed to normal height to realize GPS height transformation. Case studies demonstrate that the method is suitable for large-scale gravity exploration.

The development of the automatic multi-profile mapping plug-in is based on GeoProbe plug-in platform owned by the airborne geophysical department and Microsoft Visual Studio.Net language platform, using the development interface provided by ArcEngine software. According to the requirement of the user, the plug-in can draw the multiple parameters characteristics of the same field profile measurements in the forms of histogram, curve, or gradient rendering profile within a page, which not only depicts the topography and the physical and geochemical characteristics of the studied object but also provides audio-visual anomaly analysis and comparison. In addition, it can be used directly as the picture of a report.

With the miniaturization of the field test equipment, the integration of the embedded system intelligent portable field test equipment is more and more widely applied; nevertheless, the data collection ways and methods for equipment test are different, which will affect the internet interaction energy between the equipment and the computer and restrict its use. With the help of the Internet of things technology, these devices can be integrated to the embedded system field test equipment seamless connection, simplify the user test process, test data automatic acquisition, transmission, processing and automatic generation of various special geological map by GIS software. On the basis of the Internet of things and with the portable X-Ray fluorescence analysis instrument as an example, the authors designed a set of integrated GPS Windows Mobile intelligent mobile phone as the core of the field test data seamless acquisition and the processing system, thus improving the process of the regional geological survey and the work efficiency.

The steel plate is usually used as the liner of some concrete structures in hydropower projects. For some reason, there are usually some cavity defects in these structures. It is hence necessary to employ some non-destructive detection technology to detect these structures so as to determine the existence or nonexistence of the defects and confirm their locations and sizes. These measures provde scientific basis for the subsequent processing. The authors adopted this technology to detect cavity defects in concrete under the spiral case steel liner in a pressure pipe of a Dadu River hydropower station project. The detection results have revealed some cavity defects in the concrete and found their areas, sizes and depth ranges. The results show that the non-destructive detection technology applied in detecting cavity defects of concrete under the spiral case steel liner has an ideal effect.

Usually, city road consists of the surface layer and the subbase layer, and each layer contains several layers of different media with different relative dielectric constants. So using one relative dielectric constant to analyze the GPR data of all depths in city road detection is not accurate. This paper deduced the calculation formula of the equivalent dielectric constant of multi-layer underground media. Then the authors took two-layer media model and three-layer media model as examples to calculate the equivalent dielectric constant and the relation between the depth and the travel time. At last, theoretical modeling data of two-layer media were used to check the formula, and the results prove that the calculation formula of equivalent dielectric constant of multi-layer underground media is much better for practical GPR data analysis when there are multi-layer underground media.

Based on the basic principle of AMT and the given data, the authors has established the coal goaf interpretation criteria for profile analysis. A number of coal goafs in the exploration area were inferred according to the criteria. The verification drilling is designed to validate the dependability. The results show that this method can get fairly satisfactory effects and provide the experience concerning the detection of coal goafs.