消除采集脚印的处理方法研究

Seismic technique is in the leading position for discovering oil and gas trap and searching for reserves throughout the course of oil and gas exploration. It needs high quality of seismic processed data, not only required exact spatial position, but also the true information of amplitude and AVO attribute and velocity. Acquisition footprint has an impact on highly precision and best quality of imaging and analysis of AVO attribute and velocity. Acquisition footprint is a new conception of describing seismic noise in 3-D exploration. It is not easy to understand the acquisition footprint. This paper begins with forward modeling seismic data from the simple sound wave model, then processes it and discusses the cause for producing the acquisition footprint. It agreed that the recording geometry is the main cause which leads to the distribution asymmetry of coverage and offset and azimuth in different grid cells. It summarizes the characters and description methods and analysis acquisition footprint’s influence on data geology interpretation and the analysis of seismic attribute and velocity. The data reconstruct based on Fourier transform is the main method at present for non uniform data interpolation and extrapolate, but this method always is an inverse problem with bad condition. Tikhonov regularization strategy which includes a priori information on class of solution in search can reduce the computation difficulty duo to discrete kernel condition disadvantage and scarcity of the number of observations. The method is quiet statistical, which does not require the selection of regularization parameter; and hence it has appropriate inversion coefficient. The result of programming and tentat-ive calculation verifies the acquisition footprint can be removed through prestack data reconstruct. This paper applies migration to the processing method of removing the acquisition footprint. The fundamental principle and algorithms are surveyed, seismic traces are weighted according to the area which occupied by seismic trace in different source-receiver distances. Adopting grid method in stead of accounting the area of Voroni map can reduce difficulty of calculation the weight. The result of processing the model data and actual seismic demonstrate, incorporating a weighting scheme based on the relative area that is associated with each input trace with respect to its neighbors acts to minimize the artifacts caused by irregular acquisition geometry.

陕北何家集区延长组长4＋5－长6储层特征研究

Abstract： Hejiaji area lies on eastern part of Shanbei Slope in Ordos Basin and the primary oil-bearing bed is Chang 4＋5 and Chang 6 of Yanchang Formation. It is indicated that the sedimentary facies and reservoir characteristics restricted the hydrocarbon accumulation regularity by the geological information. Therefore, Applied with outcrop observation，core description, geophysical logging interpretation, thin section determination, Scanning Electron Microscope, reservoir lithology and physical property analysis and other analytic machinery, the sedimentary facies ,micro-characteristic and master control factors on hydrocarbon reservoir of Yanchang Formation in Hejiaji area are studied deeply by means of sedimentology，reservoir geology and petroleum geology and provide a reliably reference for later prospect . Delta facies are identified in Hejiaji area and of which distributary channels in delta plain microfacies controlled the distribution of sand bodies and accumulation of oil and gas.The distribution of sand bodies distributed from northeast to southwest are dominated by sedimentary facies . It was shown that the sandstones are medium to granule arkose，which the mud matrix is r and including，calcite，the content of matrix is lower and that mostly are cements which are mainly quartz and feldspar overgrowths and chlorite films, in the second place are hydromica and ferrocalcite. All the sandstones have entered a period of late diagenetic stage in which the dominant diagenesis types in the area are compaction, cementation and dissolution. Remnant intergranular porosity and feldspar dissolved pore are main pore types which are megalospore and medium pore. Medium-fine throat, fine throat and micro-fine throat are the mainly throat type. Pore texture can be classified as megalospore and fine throat type, medium-pore and micro-fine throat type mainly, and they are main accumulate interspace in research region. The reservoir of Yanchang Formation in Hejiaji area is low- pore and low- permeability in the mass which have strong heterogeneity in bed, interbedded and plane. Studying the parameter of pore and permeability comprehensively and consulting prevenient study results of evaluation of reservoir, the reservoir is classifiedⅡ，Ⅲ and Ⅳ three types in which the Ⅱand Ⅲ can be divided into Ⅱa and Ⅱb, Ⅲa and Ⅲb respectively. Ⅱb and Ⅲa are the main reservoir type in Hejiaji area which are about 72.73％and 80％percent of whole reservoir and effective reservoir respectively.

陕北地区石家湾-李家岔探区三叠系延长组石油成藏条件分析

Shijiawan –Lijiacha area, lying on the northeastern part of the Shanbei Slope of Ordos Basin, was selected as studying area. The previous explorations proved that the 2nd segment and 6th segment of the Yanchang Formation are the most important oil-bearing formations. It is indicated that the sedimentary facies and reservoir characteristics restricted the hydrocarbon accumulation regularity. Therefore, with petrology methodologies, such as outcrop observation, core description, geophysical logging interpretation, thin section determination, scanning electron microscope, as well as rock property analysis, the reservoirs was were systematically studied and characterized. The sedimentary micro-facies, seals, reservoir-seal combines, migration pathways and entrapping modes were taken into account. The author tempted to establish a base for further studies on reservoirs and on petroleum geology, and to provide some reliably geological evidences for later prospect activities. It was found that the sediments in the 2nd and 3rd segments of the Yanchang Formation in Shijiawan –Lijiacha area were deposited in braided rivers, and most sandy-bodies were identified as channel sandbars. The 4+5th and 6th segments were principally deposited in deltaic-plain environment, consisting of corresponding sub-facies such as distributary channels, natural levee, crevasse-splay and marsh. The skeleton sandy-bodies were identified as sandy sediments of distributary channels. The sand grains in reservoir in studied area possess generally low mineralogical maturity and moderate structural maturity, and the form of pores may be classified into intergranular types and dissolved types. Most reservoirs of Yanchang Formation in Shijiawan –Lijiacha area belong to extreme low-porosity low-permeability ones (type III), and the 2nd sediments belongs to low permeability one (type II) and the 6th segment belong to super low-permeability one(type Ⅳ). The reservoirs in the 2nd segment behave more heterogeneous than those in the 6th segment. The statistic analysis results show that, for 6th and 4+5th segments, the high quality reservoir-seal combines may be found everywhere in the studied area except in the northwest and the southwest parts; and for 1st and 2nd segments, in the northeast, central and southwest parts Petroleum migration happened in the duration of the Early Cretaceous period in both lateral and vertical directions. The migration paths were mainly constructed by permeable sandy-bodies. The superimposed channel sandy-bodies consist of the principal part of the system of carriers. the vertical fractures, that may travel through the seals between reservoirs, offered the vertical paths for migrating oil. It may be synthesized that oil coming from south kitchens migrated first laterally in carriers in the 6th segment. When arrived at the studied area, oil will migration laterally or/and vertical within both the sandy-bodies and fractures, in a climbing-stair way. The results demonstrate that the oil was entrapped in traps structure-lithology and/or lithology traps. In some cases, the hydrodynamic force may help to trap oil. Accumulation of oil in the area was mainly controlled by sedimentary facies, seals, structure, and heterogeneity of reservoir in the 2nd, 4+5th and 6th segments. Especially, the oil distributions in both the 2nd and 6th segments were obviously influenced by seals in the 4+5th segment. The existence of seals in 1st segment seems important for accumulation in the 2nd segment.

陕北桥镇油田延长组长2、长1油层组沉积相及储层研究

The Ordos Basin is a large-scale craton superimposed basin locating on the west of the North China platform, which was the hotspot of interior basin exploration and development. Qiaozhen oil field located in the Ganquan region of south-central of Ordos Basin. The paper is based on the existing research data, combined with the new theory and progress of the sedimentology, sequence stratigraphy, reservoir sedimentology, petroleum geology, etc, and analyzes systematically the sedimentary and reservoir characteristics in the chang2 and chang1 oil-bearing strata group of Yanchang formation On the basis of stratigraphic classification and comparison study, the strata chang2 and chang1 were divided into five intervals. Appling the method of cartography with single factor and dominance aspect, we have drawn contour line map of sand thickness, contour line map of ratio between sand thickness and stratum thickness. We discussed distribution characteristics of reservoir sand body and evolution of sedimentary facies and microfacies. And combining the field type section , lithologic characteristics, sedimentary structures, the sedimentary facies of single oil well and particle size analysis and according to the features of different sequence, the study area was divided into one sedimentary facies、three parfacies and ten microfacies. The author chew over the characteristics of every facies, parfacies and microfacies and spatial and temporal distribution. Comprehensive research on petrologic characteristics of reservoir , diagenesis types, pore types, distribution of sand bodies, physical properties, oiliness, reservoir heterogeneities, characteristics of interlayer, eventually research on synthetic classifying evaluation of reservoir.The reservoir is classified four types: Ⅰ、Ⅱ、Ⅲ、Ⅳ and pore type, fracture-porosity type. Take reservoir's average thickness, porosity, permeability, oil saturation and shale content as parameters, by using clustering analysis and discriminant analysis, the reservoir is classified three groups. Based on the evaluation, synthetizing the reservoir quality, the sealing ability of cap rock, trap types, reservoir-forming model ,in order to analyze the disciplinarian of accumulation oil&gas. Ultimately, many favorable zones were examined for chang23，chang223，chang222，chang221，chang212，chang12，chang11 intervals. There are twenty two favorable zones in the research area. Meanwhile deploy the next disposition scheme.

复杂断块油气藏成藏机理和剩余油预测

Complex fault block reservoir is very important type in chinese oilfield.The reservoir have for many years and it has been the important issue of oil-gas exploration and development in china that how to increase reserves and production. Therefore,taking the Pucheng-oil field as an example, the article intensive study the geologic feature of oil pool, correctly recognize the rule of oil-gas accumulation and based on the fine representation of the characteristic of reservoir, research the remaining oil in high developed area,which is important for progressive exploratioon and development and taping the remaining oil. The article multipurpose uses the data of geology,drilling,wellloging, analysis and assay and so on, under the guidance multi-disciplinary theory, intensify the comprehension of the geologic feature of oil pool in high developed oil field. Based on the high-resolution sequence stratigraphic framework ,the article points out that Es_2 upper 2+3 reservoir in the south area of Pucheng oilfield is in the depositional environment of Terminal Fan, which has constant supply of sedimentary source ,and build the sedimentation model. Studies have shown that the major reservoir in work area is the distributary channel sandbody in central Sub-facies of Terminal Fan，secondary is both lateral accretion sandbodies of channel sands，nearby and far away from the channel overflowing sandbodies in front of the fan. The article analyze the effect of depth of burial of the reservoir, sandstone structure, strata pressure and bioturbate structure on control action of physical property for reservoir and indicate that deposition and diagenesis are major controlling factors.By building the model of reservoir heterogeneity, the article show the magnitude of reservoir heterogeneity ,the genesis and identification mark of Interlayer and build the the model of interlayer. in this area the vertical distribution of interlayer is complicated,but the intraed interlayer distribute steady. Thick interlayer is steady and the thin is relatively spreaded. By building models of fault sealing,stress field and fluid potential field of the south of the pucheng oil field, the regular pattern of fluid migration and accumulation runs out. By researching the elements of oil accumulation, migration pathway and accumulation period with quantification and semiquantitative methods,we bulit the oil-gas reservoir-forming mode of the south of the pucheng oil field,which will be the foundation of the rolling exploratory development in the future. We promulgated the master control element and the rule of distribution of the remaining oil with the upside 2+3 oil layer in shaer in the south of the pucheng oil field as an example.In this area, the formation and the distribution of the remaining oil is controled by the sedimentary microfacies, reservoir heterogeneity,fault and reservoir engineering. The remaining oil is concentrated in the vicinity of the gas cap, updip of the fault block and the area with incomplete flooding. Remaining oil saturation in some area can get 50%, so there are many places in which we can enhance oil recovery.

扬子地区上奥陶－下志留统黑色岩系形成机理

The black rock series of the Upper Ordovician - Lower Silurian in Yangtze area are important source rocks and have exceptional characteristics of sediment, biology, element geochemistry, carbon and oxygen isotope, organic geochemistry and etc. These characteristics are the reflection of important geology events. Due to scarce system research, many problems that relate to the development mechanism of source rocks are not solved. And this restricts the exploration of Oil and gas in South China. In this paper, author studied the palaeo-climate, palaeo-structure and palaeo-environment of the Upper Ordovician - Lower Silurian in Yangtze area by sedimentology, palaeobiology and geochemistry, especially the element geochemistry and isotope geochemistry. The environment model of source rocks is established and some conclusions are drawn. The Upper Ordovician - Lower Silurian sediment types in Yangtze area are mostly black shales, next, mudstone, shell limestone and siltystone. During the Late Ordovician and Earily Silurian periods, a series of big upheaval and depressed are distributed in Yangtze area, and the strata pattern of interphase upheaval and depressed led to Yangtze palaeosea isolated with outside sea. So the stagnant and anoxic environment that are the favorable factor of rich organic black shales sediment is formed in Yangtze area. That Chemical Index of Alteration (CIA) values of the lower Wufeng formation and Longmaxi formation exhibits moderate chemistry weathering suggests they were deposited under the circumstances of the warm and humid climate. However, the large difference of the CIA values of N.extraordinarius-N.ojsuensis biozone suggests that climate is changeful. Therefore, there were two different kinds of climates in the course of the deposition of the Wufeng formation and Longmaxi formation. During the Late Ordovician - Earily Silurian periods, in Yangtze palaeosea, the surface water which is full of rich nutriment and abundant bacterium - algae has high palaeo-productivity that is obvious difference in the different space – time. The content of sulphate changes gradually from the surface water columns to the deep water columns. That is, salinity in the surface water columns is serious low and the salinity in deep water columns is normal. Salinity delamination is favor of the forming of deep anoxic environment. During Wufeng period, the oxidated and low sulfate environment exists in the upper Yangtze palaeosea, while the anoxic and normal salinity environment occurs in the lower Yangtze palaeosea. During the Late Wufeng and Guanyinqiao periods, the steady anoxic environment is replaced by oxidated environment. During the Longmaxi period, layered and anoxic environment recur. In Yangtze area, studies of δ13C of sedimentary organic carbon show a positive δ13C excursion up to 4‰ in the Guanyinqiao stage and then, acute negative excursion in the earily Longmaxi stage. These organic carbon isotopes curve are not only efficient measure of carving up strata borderline, but also reflected the change of originality productivity. These organic carbon isotopes curves showed the process of the enhanced embedding of the global organic carbon. Anoxic event is the main factor of increasing organic carbon embedding speed. And the reduced organic carbon embedding in Hirnantian stage is due to the water column with abundant oxygen. The δ34S values are gradually positive excursion from P.pacificus biozone to N.extraordinarius biozone, and reach the maximum in the Upper Hirnantian stage. Then, the δ34S values are negative excursion. The excursions of δ13C and δ34S reflect the acute change of environment. The formation of source rocks is largely dependent on the nature of organisms from which kerogen is derived and the preservation conditions of organic matter, which are fundamentally dependent on a favourable combination of various elements in which organisms live and are subsequently buried. These elements include palaeoclimate, palaeostructure and palaeoenvironmental conditions. Based on above mentioned circumstance, the coupling connection of source rock and the palaeoclimate, and of palaeostructure and palaeoenvironmental conditions are confirmed, and the “anoxic-marginal depression-photosynthesis” environemental model is established. It is indicated that anoxic played important role in production of organic matter. The produced organic matter was accumulated in marginal depression of the Yangtze area. The photosynthesis is favor of the high productivity. Source rocks have a good perspective, like that of “hot shale” deposited in North Africa.

岩体力学参数及稳定性能量判据研究

There are two major problems that have been concerned all the times, which are the mechanics characters of joint rock mass and the criterion for stability of engineering rock. Aim at the two problems, several works were conducted as follow: (1) Firstly, the mechanics characters of rock mass was studied by means of the Distinct Element Code. Subsequently, it was studied that the sensibility of joint surface roughness, strength of joint wall, joint stiffness ( i.e. tangential and normal stiffness) on the rock mass strength. (2) Based on the experimental rock mass classification methods of RMR and GSI, the program of “Parameters Calculation of the Rock Mass ” was developed. It has realized the rapid choice of rock mass parameters. (3) The concept of Representive Element Volume was induced based on the study of dimensional effect of rock mass. The Representive Element Volume of the horizontal and vertical pillar (ab. Two Pillars ) in the 2nd zone of Jinchuan mine were gained by the Geology Statistic Method and the Distinct Element Code. And then, the strength and deformatiom parameters of rock mass of the Two Pillars were obtained through numerical experiment. (4) From the confining depressure after thriaxial compression test of rock sample, it was concluded that the failure of rock is caused mainly by the lateral deformation and energy release happened during the confining depressure processure. The criterion of plastic energy catastrophe of rock engineering failure was proposed and validated. Subsquently, the stability of the horizontal pillar and Qianjiangping landslide in Three Gorges was judged by means of above-mentioned method. (5) Based on the fact there is a phenomenon of increasing energy concentration while the rock mass was compressed, rock information entropy (i.e. energy distribution entropy) was proposed. And it was revealed that there was change of energy distribution entropy while the rock mass was compressed to failure.

典型人类活动对边坡变形及稳定性的影响研究

China is a mountainous country in which geological hazards occurred frequently, especially in the east of China. Except the geology, topography and extreme climate, the large scale human activities have become a major factor to landslides. Typical human activities which induced landslides are fill, cut and underground mining. On the topic of the deformation mechanism and slope stability, taking three different man-made slopes as examples, deformation mechanism and slope stability were studied by several methods, such as field work, numerical modeling and monitor. The details are as following: (1) The numerical modeling approach advantages over other conventional methods such as limit methods, so the numerical modeling is the major tool in this thesis. So far, there is no uniform failure criterion for numerical simulation. The failure criterion were summarized and analyzed firstly, subsequently the appropriate criterion was determinated. (2) Taking 220kV Yanjin transformation substation fill slope as example, the deformable characteristic, unstable mode and laboratory tests were studied systematically. The results show: the slope deformation was probably caused by a combination effect of unfavorable topographic, geological and hydro geological conditions, and external loading due to filling. It was concluded that the creep deformation of the slope was triggered by external loading applied at the back of the slope. In order to define the calculating parameters, a set of consolidated drained (CD) tests, consolidated undrained (CU) tests, repeated direct shear tests and UCS tests were carried out. The stability of the slope before and after reinforcement was assessed using 3D numerical modeling and shear strength reduction technique. The numerical modeling results showed: the factor of safety (FOS) of the slope was 1.10 in the natural state, and reduced to 1.03 after fill, which was close to the critical state and it caused creeping slip or deformation under rainfall. The failure surface in the slope is in active shear failure, whereas tensile failure occurs at the slope crest. After the site was reinforced with piles, the FOS was 1.27. Therefore, the slope is stable after reinforcement measures were taken. (3) The cut slope stability is a complex problem. Taking the left cut slope of Xiangjiaba as example in this thesis, the deformation and slope stability were studied systematically by numerical modeling and monitor methods. The numerical results show: the displacement is gradually increasing along with the cutting, and the largest displacement is 27.5mm which located at the bench between the elevation 340 and 380. Some failure state units distribute near the undermining part and there is no linked failure state occurred from crest to bottom during cutting. After cutting, some failure units appeared at the ground surface between elevation 340 and 360. The increasing tense stress made the disturbed rock failed. The slope is stable after cutting by the monitor method, such as surface monitor, multipoint displacement meter, inclinometer and anchor cable tensometer. (4) The interaction between underground mining and slope stability is a common situation in mountainous. The slope deformation mechanism induced by underground mining may contributed significantly to slope destabilization. The Mabukan slope in xiangjiaba was analyzed to illustrate this. Failure mechanism and the slope stability were presented by numerical modeling and residual deformation monitor. The results show: the roof deformed to the free face and the floor uplift lightly to the free face. The subsidence basin is formed, but the subsidence and the horizontal movement is small, and there is no failure zone occurred. When the underground mining is going on, the roof deformation, subsidence and the horizontal movements begin increasing. The rock deformation near the free face is larger than the ground surface, and the interaction between these coal seams appeared. There are some tensile failures and shear failures occurred on the roof and floor, and a majority of failure is tensile failure. The roof deformation, subsidence and the horizontal movements increased obviously along with the underground mining. The failure characteristic is shear failure which means the tensile stress transformed to the compressive stress. So the underground mining will induced tensile stress first which lead to structure crack, subsequently the compressive stress appeared which result in slippage. The crest was subjected to horizontal tension which made the rock crack along with the joint. The long term residual deformation monitor demonstrates that the slope is stable after the underground mining stopped.

基于精细结构描述及数值试验的断续节理岩体力学参数智能选取

Evaluating the mechanical properties of rock masses is the base of rock engineering design and construction. It has great influence on the safety and cost of rock project. The recognition is inevitable consequence of new engineering activities in rock, including high-rise building, super bridge, complex underground installations, hydraulic project and etc. During the constructions, lots of engineering accidents happened, which bring great damage to people. According to the investigation, many failures are due to choosing improper mechanical properties. ‘Can’t give the proper properties’ becomes one of big problems for theoretic analysis and numerical simulation. Selecting the properties reasonably and effectively is very significant for the planning, design and construction of rock engineering works. A multiple method based on site investigation, theoretic analysis, model test, numerical test and back analysis by artificial neural network is conducted to determine and optimize the mechanical properties for engineering design. The following outcomes are obtained: (1) Mapping of the rock mass structure Detailed geological investigation is the soul of the fine structure description. Based on statistical window，geological sketch and digital photography，a new method for rock mass fine structure in-situ mapping is developed. It has already been taken into practice and received good comments in Baihetan Hydropower Station. (2) Theoretic analysis of rock mass containing intermittent joints The shear strength mechanisms of joint and rock bridge are analyzed respectively. And the multiple modes of failure on different stress condition are summarized and supplied. Then, through introducing deformation compatibility equation in normal direction, the direct shear strength formulation and compression shear strength formulation for coplanar intermittent joints, as well as compression shear strength formulation for ladderlike intermittent joints are deducted respectively. In order to apply the deducted formulation conveniently in the real projects, a relationship between these formulations and Mohr-Coulomb hypothesis is built up. (3) Model test of rock mass containing intermittent joints Model tests are adopted to study the mechanical mechanism of joints to rock masses. The failure modes of rock mass containing intermittent joints are summarized from the model test. Six typical failure modes are found in the test, and brittle failures are the main failure mode. The evolvement processes of shear stress, shear displacement, normal stress and normal displacement are monitored by using rigid servo test machine. And the deformation and failure character during the loading process is analyzed. According to the model test, the failure modes quite depend on the joint distribution, connectivity and stress states. According to the contrastive analysis of complete stress strain curve, different failure developing stages are found in the intact rock, across jointed rock mass and intermittent jointed rock mass. There are four typical stages in the stress strain curve of intact rock, namely shear contraction stage, linear elastic stage, failure stage and residual strength stage. There are three typical stages in the across jointed rock mass, namely linear elastic stage, transition zone and sliding failure stage. Correspondingly, five typical stages are found in the intermittent jointed rock mass, namely linear elastic stage, sliding of joint, steady growth of post-crack, joint coalescence failure, and residual strength. According to strength analysis, the failure envelopes of intact rock and across jointed rock mass are the upper bound and lower bound separately. The strength of intermittent jointed rock mass can be evaluated by reducing the bandwidth of the failure envelope with geo-mechanics analysis. (4) Numerical test of rock mass Two sets of methods, i.e. the distinct element method (DEC) based on in-situ geology mapping and the realistic failure process analysis (RFPA) based on high-definition digital imaging, are developed and introduced. The operation process and analysis results are demonstrated detailedly from the research on parameters of rock mass based on numerical test in the Jinping First Stage Hydropower Station and Baihetan Hydropower Station. By comparison，the advantages and disadvantages are discussed. Then the applicable fields are figured out respectively. (5) Intelligent evaluation based on artificial neural network (ANN) The characters of both ANN and parameter evaluation of rock mass are discussed and summarized. According to the investigations, ANN has a bright application future in the field of parameter evaluation of rock mass. Intelligent evaluation of mechanical parameters in the Jinping First Stage Hydropower Station is taken as an example to demonstrate the analysis process. The problems in five aspects, i. e. sample selection, network design, initial value selection, learning rate and expected error, are discussed detailedly.

大型反倾岩体变形破坏机制及稳定性分析———以金沙江宽谷坝址龙蟠边坡为例

A large number of catastrophic accidents were aroused by the instability and destruction of anti-dip rock masses in the worldwide engineering projects, such as hydropower station, mine, railways and so on. Problems in relation to deformation and failure about anti-dip rock slopes are significant for engineering geology research. This dissertation takes the Longpan slope in the Jinsha River as a case to study the deformation mechanism of large-scale anti-dip rock masses and the slope stability analysis method. The primary conclusions are as follows. The Dale Reach of Jinsha River, from Longpan to the debouchment of Chongjiang tributary, is located in the southeastern margin of the Qinghai-Tibet Plateau. Longpan slope is the right embankment of Dale dam, it is only 26 km to the Shigu and 18 km to Tiger Leaping Gorge. The areal geology tectonic structures here area are complicated and blurry. Base on the information of geophysical exploration (CSAMT and seismology) and engineering geological investigation, the perdue tectonic pattern of Dale Reach is put forward for the first time in this paper. Due to the reverse slip of Longpan fault and normal left-rotation of Baihanchang fault, the old faulted valley came into being. The thick riverbed sediments have layered characters of different components and corresponding causes, which attribute to the sedimentary environments according with the new tectonic movements such as periodic mountain uplifting in middle Pleistocene. Longpan slope consists of anti-dip alternate sandstone and slate stratums, and the deformable volume is 6.5×107m3 approximately. It was taken for an ancient landslide or toppling failure in the past so that Dale dam became a vexed question. Through the latest field surveying, displacement monitoring and rock masses deforming characters analyses, the geological mechanism is actually a deep-seated gravitational bending deformation. And then the discrete element method is used to simulate the deforming evolution process, the conclusion accords very well with the geo-mechanical patterns analyses. In addition strength reduction method based on DEM is introduced to evaluate the factor of safety of anti-dip rock slope, and in accordance with the expansion way of the shear yielding zones, the progressive shear failure mechanism of large-scale anti-dip rock masses is proposed for the first time. As an embankment or a close reservoir bank to the lower dam, the stability of Longpan slope especially whether or not resulting in sliding with high velocity and activating water waves is a key question for engineering design. In fact it is difficult to decide the unified slip surface of anti-dip rock slope for traditional methods. The author takes the shear yielding zones acquired form the discrete element strength reduction calculation as the potential sliding surface and then evaluates the change of excess pore pressure and factor of stability of the slope generated by rapid drawdown of ponded water. At the same time the dynamic response of the slope under seismic loading is simulated through DEM numerical modeling, the following results are obtained. Firstly the effective effect of seismic inertia force is resulting in accumulation of shear stresses. Secondly the discontinuous structures are crucial to wave transmission. Thirdly the ultimate dynamic response of slope system takes place at the initial period of seismic loading. Lastly but essentially the effect of earthquake load to bringing on deformation and failure of rock slope is the coupling effect of shear stresses and excess pore water pressure accumulation. In view of limitations in searching the critical slip surface of rock slope of the existing domestic and international software for limit equilibrium slope stability analyses, this article proposes a new method named GA-Sarma Algorithm for rock slope stability analyses. Just as its name implies, GA-Sarma Algorithm bases on Genetic Algorithm and Sarma method. GA-Sarma Algorithm assumes the morphology of slip surface to be a broken line with traceability to extend along the discontinuous surface structures, and the slice boundaries is consistent with rock mass discontinuities such as rock layers, faults, cracks, and so on. GA-Sarma Algorithm is revolutionary method that is suitable for global optimization of the critical slip surface for rock slopes. The topics and contents including in this dissertation are closely related to the difficulties in practice, the main conclusions have been authorized by the engineering design institute. The research work is very meaningful and useful for the engineering construction of Longpan hydropower station.

岩石磨蚀性和TBM滚刀磨损机理研究

Using the popular CERCHAR testing to measure the abrasiveness of rock which is CERCHAR abrasiveness index(CAI). The digital imagine processing program IPP is used to quantify the rock texture such as the grain size, the shape of grain and the index of grain homogeneity. And the rock mechanical testing machine are used to measure the strength, hardness and elastic modulus. Basic on these three experiments, this paper finds the relationship between the CAI and physical and mechanical properties of rock. They are both the mesostructure and macroscopical properties of rock. According to the theory of tribology and wear, this paper finds the disc cutter wear mechanism during the machine and rock interaction process. The detail research results are as follows: (1) The size and form of the mineral grains constituting the rocks affect the abrasiveness of the rock. The rock abrasiveness CAI is a function of the product of the texture coefficient(TC) multiplying equivalent quarts content(Q%). (2) There is no obvious relationship between the rock abrasiveness CAI and the single macroscopical property of rock such as hardness, unconfined compressive strength, tensile strength and elastic modulus. But when taking the texture coefficient(TC) and the mineral composition in consideration, it shows that the rock abrasiveness CAI is relative to the combination of the rock mechanical property, the texture coefficient(TC) and the mineral composition. That is to say various factors which are from the mesostructure feature to the macroscopical property of rock control the rock abrasiveness. (3) The disc cutter penetrating into rock is a machine/rock interaction process. During this interaction, the wear of disc cutter is mainly coming from the abrasive of abrasiveness matters. First, the surface of the cutter ring is hunched, and then the material of the cutter ring is being wiped off during the iterative interaction. Second, the hard mineral in the rock and the muck will microcosmic cutting the surface material of cutter ring. (4) The disc cutters consumption is determined by the machine parameters and the geology condition. The machine parameters include the thrust and the revolution rate of the cutterhead. The geology condition include two aspects: the macroscopical properties which are the strength and/or hardness of rock, the presence of discontinuities in rock mass, the hardness, sharp, edge and size of the muck and so on. And the mesostructure features which are the hard mineral composition, the sharp and size of the grain of the rock.

基于GIS的滑坡危险度区划定量研究

Abstract With the Development of the West Regions, the contradiction between economy and geological hazards was once again brought to our face in the Loess Plateau where was ,and is liable to geological hazards for the unique conditions of geology, hydrogeology, geography and meteorology. The goal to realize harmonious development between human and the earth was always there, and landslide hazard zoning provided us an effective way against geological hazards and damage. In the background of the construction of 750KV transformer substation in TianShui, we summarized some theories, methods and development of landslide hazard zoning and discussed the application of information value model in landslide hazard zoning. A called “judgement matrix” like in AHP was introduced to the information value model to solve the key point of landslide hazard zoning — choice of factors and weight of each factor. GIS was applied in the landslide hazard zoning, with its comprehensive function on data management, spatial analysis and mapping. A zonation map of landslide hazard was worked out on MAPGIS aimed to have something of reference and instruction on the construction of the transformer substation. Key words: landslide; hazard zoning; information value model; GIS; judgement matrix

叠前时间偏移：各向异性、多次波衰减及应用

At present, in order to image complex structures more accurately, the seismic migration methods has been developed from isotropic media to the anisotropic media. This dissertation develops a prestack time migration algorithm and application aspects for complex structures systematically. In transversely isotropic media with a vertical symmetry axis (VTI media), the dissertation starts from the theory that the prestack time migration is an approximation of the prestack depth migration, based on the one way wave equation and VTI time migration dispersion relation, by combining the stationary-phase theory gives a wave equation based VTI prestack time migration algorithm. Based on this algorithm, we can analytically obtain the travel time and amplitude expression in VTI media, as while conclude how the anisotropic parameter influence the time migration, and by analyzing the normal moveout of the far offset seismic data and lateral inhomogeneity of velocity, we can update the velocity model and estimate the anisotropic parameter model through the time migration. When anisotropic parameter is zero, this algorithm degenerates to the isotropic time migration algorithm naturally, so we can propose an isotopic processing procedure for imaging. This procedure may keep the main character of time migration such as high computational efficiency and velocity estimation through the migration, and, additionally, partially compensate the geometric divergence by adopting the deconvolution imaging condition of wave equation migration. Application of this algorithm to the complicated synthetic dataset and field data demonstrates the effectiveness of the approach. In the dissertation we also present an approach for estimating the velocity model and anisotropic parameter model. After analyzing the velocity and anisotropic parameter impaction on the time migration, and based on the normal moveout of the far offset seismic data and lateral inhomogeneity of velocity, through migration we can update the velocity model and estimate the anisotropic parameter model by combining the advantages of velocity analysis in isotropic media and anisotropic parameter estimation in VTI media. Testing on the synthetic and field data, demonstrates the method is effective and very steady. Massive synthetic dataset、2D sea dataset and 3D field datasets are used for VTI prestack time migration and compared to the stacked section after NMO and prestack isotropic time migration stacked section to demonstrate that VTI prestack time migration method in this paper can obtain better focusing and less positioning errors of complicated dip reflectors. When subsurface is more complex, primaries and multiples could not be separated in the Radon domain because they can no longer be described with simple functions (parabolic). We propose an attenuating multiple method in the image domain to resolve this problem. For a given velocity model，since time migration takes the complex structures wavefield propagation in to account, primaries and multiples have different offset-domain moveout discrepancies, then can be separated using techniques similar to the prior migration with Radon transform. Since every individual offset-domain common-reflection point gather incorporates complex 3D propagation effects, our method has the advantage of working with 3D data and complicated geology. Testing on synthetic and real data, we demonstrate the power of the method in discriminating between primaries and multiples after prestack time migration, and multiples can be attenuated in the image space considerably.

内蒙古龙头山Ag-Pb-Zn多金属矿床成矿模式及找矿模型

The recent years research indicated that middle-south section of Da Hinggan Mountains metallogenic belt has two periods(Hercynian and Yanshanian) characteristics of metallogenesis, as well as the most of ore deposits in the area closely relate to Permian strata. Longtoushan ore deposit discovered in 2004 is an Ag-Pb-Zn polymetallic ore deposit born in Permian and located in the east hillside of the metallogenic belt, which has considerable resources potentials. It has important research value for its good metallogenic location and blank research history. Base on the detail field geology studies, the geology characteristics of "two stages and three kinds of metallogensis" has established. According to further work through geochemistry research including trace element, REE, S, Pb and Sr isotope, as well as petrography, microtemperature measurement, Laser Raman analysis and thermodynamics calculation of fluid inclusion, origin and characteristic of the ore-forming material and fluid has been discussed. And a new technology of single pellet Rb-Sr isochrones has been tried for dating its born time. Bae on above work, study of ore deposit comparison has been carried out, and metallogesis controlling factor and geological prospecting symbol have been summarized. Finally, metallogenic model and prospecting model have been established. According to above, the next step work direction has been proposed. Main achievement of the paper are listed as follow: 1.Longtoushan ore deposit has experienced two metallogenic periods including hot-water sedimentation period and hydrothermal reformation period. There are three kinds of metallizing phase: bedded(or near-bedded) phase, vein-shaped phase and pipe-shaped phase. The mian metallogenic period is hot-water sedimentation period. 2.Ore deposit geochemistry research indicated that the metal sulfides have charcateristic of hot-water sedimentation metallogensis, but generally suffered later hydrothermal transformation. The barite mineral isotope content is homogenous, showing the seabed hot-water sedimentation origin characteristic. Wall rock, such as tuff is one of metallogenic material origins. Both of Pb model age and Rb-Sr isochrone research older age value than that of strata, possibly for been influenced by hydrothermal transformation, and interfusion of ancient basis material. 3.There are two kinds of main metallogenic fluid inclusion in barite of the Longtoushan ore deposit, which are rich gas phase( C type) and liquid phase (D type). Their size is 2～7um, and principal components is H2O. Both kinds of fluid inclusion have freezing point temperature -7.1～-2.4℃ and -5.5～-0.3℃, salinity 4.0～10.6wt% and 0.5～8.5wt%, homogeneous temperature 176.8～361.6℃ and 101.4～279.9℃, which peak value around 270℃ and 170℃, respectively. Density of the ore-forming fluid is 0.73～0.97g/cm3, and metallogenic pressure is 62.3×105～377.9×105Pa. Above characteristic of the fluid inclusion are well geared to that of ore deposit originated in seabed hot-water sedimentation. 4.Through the comparison research, that Longtoushan ore deposit has main characteristic of hot-water sedimentation ore deposit has been indicated. Ore-forming control factor and prospecting symbol of it has been summarized, as well as metallogenic model and prospecting model. Next step work direction about prospecting has also been proposed finally.

北山及邻区古生代-早中生代增生与碰撞大地构造格局

The Beishan orogenic collage locates at the triple-joint among Xinjiang, Gansu, and Inner Mongolia Provinces, at which the Siberian, Tarim and North China plates join together. It also occupies the central segment of the southern Central Asian Orogenic Belt (CAOB). The main study area in the present suty focused on the southwest part of the Beishan Mountain, which can be subdivided into four units southernward, the Mazhongshan continental block, Huaniushan Arc, Liuyuan suture zone and Shibanshan-Daqishan Arc. 1. The Huaniushan Arc was formed by northernward dipping subduction from the Orcovician to Permian, in which volcanic rocks ranging from basic to acidic with island arc affinity were widely developed. The granitiod intrusions become smaller and younger southward, whichs indicates a southward rollback of slab. The granitiod intrusions are mainly composed of I type granites, and their geochemical compositions suggest that they have affinities of island arc settings. In the early Paleozoic（440Ma-390Ma）. The Shibanshan-Daqishan Arc, however, were produced in the southernward dipping subduction system from Carboniferous to Permian. Volcanic rocks from basic to acidic rocks are typical calcic-alkaline rocks. The granitiod intrusions become smaller and younger northernward, indicating subdution with a northernward rollback. The granitiod intrusions mainly consist of I-type granites, of which geochemical data support they belong to island arc granite. 2. Two series of adakite intrusions and eruptive rocks have been discovered in the southern margin of the Huaniushan Island Arc. The older series formed during Silurian (441.7±2.5Ma) are gneiss granitoid. These adakite granites intruded the early Paleozoic Liuyuan accretionary complex, and have the same age as most of the granite intrusions in the Huanniushan Arc. Their geochemical compostions demonstrate that they were derived from partial melting of the subudcted oceanic slab. These characteristics indicate a young oceanic crust subduction in the early Paleozoic. The late stage adakites with compositons of dacites associate with Nb-enriched basalts, and island arc basalts and dacites. Their geochemistries demonstrate that the adakites are the products of subducted slab melts, whereas the Nb-enriched basalt is products of the mantle wedge which have metasomatized by adakite melts. Such a association indicates the existences of a young ocean slab subduction. 3. The Liuyuan suture zone is composed of late Paleozoic ophiolites and two series of accretionary complexes with age of early Paleozoic. The early Paleozoic accretionary complex extensively intruded by early Palozioc granites is composed of metamorphic clastics, marble, flysch, various metamorphic igneous rocks (ultramafic, mafic and dacite), and eclogite blocks, which are connected by faults. The original compositions of the rocks in this complex are highly varied, including MORB, E-MORB, arc rocks. Geochronological study indicates that they were formed during the Silurian (420.9±2.5Ma and 421.1±4.3Ma). Large-scale granitiods intruded in the accretionary complex suggest a fast growth effect at the south margin of the Huaniushan arc. During late Paleozoic, island arc were developed on this accretionary complex. The late Paleozoic ophiolite has an age of early Permian (285.7±2.2Ma), in which the rock assemblage includes ultra-mafic, gabbros, gabbros veins, massive basalts, pillow basalt, basaltic clastic breccias, and thin layer tuff, with chert on the top.These igneous rocks have both arc and MORB affinities, indicating their belonging to SSZ type ophiolite. Therefore, oceanic basins area were still existed in the Liuyuan area in the early Permian. 4. The mafic-ultramafic complexes are distributed along major faults, and composed of zoned cumulate rocks, in which peridotites are surrounded by pyroxenite, hornblendites, gabbros norite and diorite outward. They have island-arc affinities and are consistent with typical Alaska-type mafic-ultramafic complexes. The geochronological results indicate that they were formed in the early Permian. 5. The Liuyuan A-type granite were formed under post-collisional settings during the late Triassic (230.9±2.5Ma), indicating the persistence of orogenic process till the late Triassic in the study area. Geochronological results suggested that A-type granites become younger southward from the Wulungu A-type granite belt to Liuyuan A-type granite belt, which is in good agreement with the accretionary direction of the CAOB in this area, which indicate that the Liuyuan suture is the final sture of the Paleo-Asin Ocean. 6. Structural geological evidence demonstrate the W-E spreading of main tectonic terrenes. These terrenes had mainly underwent through S-N direction contraction and NE strike-faulting. The study area had experienced a S-N direction compression after the Permian, indicating a collisional event after the Permian. Based on the evidene from sedimentary geology, paleontology, and geomagnetism, our studies indicate that the orogenic process can be subdivided into five stages: (1) the pre-orogenic stage occurred before the Ordovicain; (2) the subduction orogenic stage occurred from the Orcovician to the Permian; (3) the collisional orogenic stage occurred from the late Permian to the late Triassic; (4) the post-collision stage occurred after the Triassic. The Liuyuan areas have a long and complex tectonic evolutional history, and the Liuyuan suture zone is one of the most important sutures. It is the finally suture zone of the paleo-Asian ocean in the Beishan area.