668 resultados para Bunter sandstone


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The topic of Dynamic reservoir model and the distribution of remaining oil after polymer injection of Shengtuo oilfield is a front problem of "the 11th Five-Year Plan" scientific and technological disciplines of Sinopec Corporation. Reservoirs in study area is distributary channel sandstone. After 34 years of water-injection exploitation and 7 years of polymer injection pilot experiments, a highly complex heterogeneous dynamic evolution has been occurred in macro and micro parameters of reservoir model, together with its flow field. Therefore, it’s essential to construct completed reservoir dynamic model for a successfully prediction of the distribution of remaining oil. With a comprehensive application of multidisciplinary theory and technique, using a variety of data and information to maximize the use of computer technology, combining a static and dynamic, macro and micro and 1~4D integration, the research reveals main features, evolution and mechanism, types of geological disasters and their destructivity of reservoir flow field, the macro field, the micro field, the flow field and reservoir development hydrodynamic geological function in different development periods after a long term of polymer injection in Es2 in Shengtuo oilfield. The principle innovation achievements obtained are: 1. Established A, B, C, D four flow units in target formations, revealed the various features and distribution of flow units. 2. Stated environmental pollution and geological disasters induced during oilfield exploitation in study area, and also explained their formation mechanism, controlling factors, destructivity and approaches to disaster reduction. 3. Established dynamic evolution of the macro parameter model, micro-matrix field, pore network field, clay minerals field, seepage dynamic evolution model of six different exploitation stages in study area, also revealed reservoir flow evolution, the law of evolution mechanism after polymer injection. 4. Established macro and micro distribution model of remaining oil after three mining polymer injection during different water cut periods in study area, revealed the formation mechanism and distribution of remaining oil. 5. Established remaining oilforecasting model in study area, and forecasted the formation and distribution of remaining oil in the following six years. 6. It is proposed that reservoir fluid dynamic geological processes are major driving forces for the evolution of different water cut periods, reservoir macro field after the polymer injection and micro seepage field. 7. Established a dynamic reservoir model, proposed matching theory, methods and technology for the description of the remaining oil characterization and prediction, which can deepen the theory and techniques of continental rift basin development geology. Key words: Polymer reservoir; Geological disasters; Dynamic model; Residual oil forecast

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It has been long known that intense multiple Mesozoic-Cenozoic intracontinental deformations have controlled the grand scale basin-range structural evolution of the Tianshan and its adjacent basins. So it is important to study the sedimentary records of the piedmont basins along the two sides of the Tianshan synthetically for the continental geodynamic research.We carried out a magnetostratigraphy study on Cretaceous- Tertiary succession and U-Pb dating analysis of detrital zircons from the representative sandstone samples of the Mesozoic-Cenozoic deposits in Kuqa Subbasin, northern Tarim Basin, combining our previous results of multiple depositional records from different profiles including paleocurrent data, conglomerate clast, sandstone framswork grains, detrital heavy minerals and geochemistry analysis, so the multiple intracontinental tectonic processes of Tianshan and their depositional response in the Kuqa Subbasin can be revealed. The results show that the tectonic evolution of the Tianshan Orogen and the sedimentary processes of the Kuqa Subbasin can be divided into four periods: early Triassic(active period), from middle Triassic to late Jurassic(placid period), from early Cretaceous to Tertiary Paleocene(active period) and from Neogene to present (intensely active period). Simultaneously,the depositional records reveal the provenance types and tectonic attributes in different periods. As follows, the lower Triassic with a dominant age ranging from 250 to 290Ma of the Zircons, which were principally derived from alkali feldspar granites and alkaline intrusion obviously, relative to the magma activity in Permian. In middle Triassic-late Jurassic, the two samples collected from the Taliqike formation and the Qiakemake formation respectively show the age peak at 350~450Ma, which was relative to the subduction of the Tarim Block to Yili-Central Tianshan Plate. In this period the provenance of the Kuqa deposits was the Central Tianshan arc orogenic belts distantly with little height predominance.During early Cretaceous-Paleogene, two major zircons age spectra at 240~330Ma and 370~480Ma have been acquired, with some other not dominant age ranges, indicating complicated provenance types. In Neogene, the detrital zircons age dating ranges from 460 to 390 Ma primarily. What’s more, the newer chronology of the stratigraphy and the older source age, indicating that Tianshan was uplifted and exhumated further strongly. Further study on the heavy mineral and the detrital zircons age dating of the Mesozoic-Paleogene representative profiles in southern Junggar Basin, combined with the published results of the sandstone framework grains, we consider that it occurred obvious sedimentary and tectonic changes occurred in the inside of Jurassic, from late Jurassic to early Cretaceous and form early Cretaceous to late Cretaceous. On this faces, there are remarkable changes of the steady minerals and unstable minerals, the sandstone maturity and the age spectra of the detrital zircons. Compared the sedimentary records from the two sides of the Tianshan, We find that they are different obviously since Middle Jurassic. It can be concluded that Tianshan have uplifted highly enough to influence the paleo-climatic. According to the current strata division, the structural activity apparently showed a migration from north to south. That is to say, the South Tianshan uplift later than the north, especially from late Jurassic to early Cretaceous , but it was uplifted and exhumated more strongly. Furthermore, correlating the depositional records and tectonic styles in the Kuqa-South Tianshan basin-range conjugation site in the east with the west, the obvious differentiation between the west and the east from the Cretaceous especially in Tertiary along the Tianshan-Kuqa belt was revealed, probably showing earlier uplifting in the east while greater exhumation depth and sediment rates in the west. In addition, the contacting style of Kuqa subbasin to the Tianshan Orogenic belts and the basement structure are also inconsistent at different basin-range conjugation sites. It is probably controlled by a series of N-S strike adjusting belts within the Kuqa subbasin, or probably correlated with the material difference at the complicated basin-range boundary. The research on the Mesozoic-Cenozoic tectonic-depositional response in the piedmont basins along the two sides of the Tianshan shows that the basin-filling process was controlled by the intracontinental multicyclic basin-range interactions, especially affected by the intense tectonic differentiations of basin-range system, which can’t be illuminated using a single evolutionary model.

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With the deeply development of exploration and development in petroleum in China, new increasing reserves are found in old oil fields and the verge of the old ones through re-study of geological property. It is more and more important to discovery and develop thin layer or thin inter-bedded layers reservoirs. All of the targets are thin sand-shale inter-bedded reservoirs and the core technology is reservoir predictions between wells in thin sand-shale inter-bedded layers. The continuity of the thin sand-shale inter-bedded layers in space or separating and heterogeneity is the key of reservoir geology research. The seismic reflection, high resolution analysis method and inversion method to thin sand-shale inter-bedded layers are thorough discussed and deeply studied in this paper to try to find the methods and resolutions of reservoir geology research. The below is followed. 1. Based on the pre-research of other people, five models are created: the sand sphenoid body, interlay sandstone and interlay shale of the equal thickness, interlay sandstone of the equal thickness and interlay shale of the unequal thickness, interlay sandstone of the unequal thickness and interlay shale of the unequal thickness, interlay sandstone of the changing thickness in sequence and interlay shale of the changing thickness in sequence. Then the study of the forward modeling are conducted on the thin layer and thin inter-bedded layers geological characters and seismic reflections including amplitude, frequency, phase, wave shape and time-frequency responding in the domains of time and frequency. The affect of petro-physics difference of layers, single thin layer thickness, thickness of inter-bedded, layer number of inter-bedded, incident wavelet domain frequency and types, sample interval to seismic reflection characters, frequency spectrum and time-frequency respond of reflectivity is theoretically discussed. 2. Qualitatively analyzing the sedimentary rhythm of the thin inter-bedded layers in vertical orientation and computing the single layer thickness or the average thickness with the method of generalized S transform. Identifying the reflecting interface or lithology interface using the amplitude value of amplitude spectrum domain frequency. 3. Based on the seismic respond of thin sand-shale inter-bedded layers, bring out the high resolution analysis method of seismic data in thin sand-shale inter-bedded layers using wavelet analysis and the idea of affecting low and high frequency with middle frequency. Then analyzing the effect to the method and testing some wavelets in the method. This method is applied to the theoretical models and the field data. 4. Bring forward one improved very fast simulated annealing method (IVFSA) to resolve the problem nonlinearity and multi-parameters of the inversion in thin inter-bedded layers. And IVFSA is more productive and higher precision than general ways. 5. New target constrained function is used in the inversion based on the property of the inversion in thin inter-bedded layers. 6. Making the full use of geological and logging information, IVFSA and the new function are applied in the non-linear inversion to improve reservoir prediction and evaluation in thin inter-bedded formations combined with the idea of logging and seismic inversion. This method was applied to the field data and got good results.

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Luo Ning ( Mineralogy, Petrology, Deposit Mineralogy) Directed by Fu Liyun With the increase of the level of exploration and development, North China field, as one of the maturing fields in the east, has gradually turned their prospecting targets to frontiers such as deep zones, lithologic hydrocarbon reservoirs, low permeable layers, special lithostromes, etc, which propose new challenges to mating technique of exploration engineering. In it, the special lithostrome of clay carbonate in Shu-Lu cave in Middle Flank exploration area locates in Es_3 generating rock. The area distribution is large, formation thickness is over 100 meters, the oil accumulation condition is excellent, prognostic reserves is over 80,000,000 tons, but how to effectively stimulate the special low permeable and fractured reservoir has become the bottle neck problem of stimulation and stable yields. In this thesis, through comprehensive evaluation and analysis of lithology, lithomechanics, hydrocarbon reservoir characteristics, the characteristics of fluid flow through porous medium and the stimulation measures in the past, we acquire new cognition of clay carbonate reservoirs, in addition, the research and application of first hydraulic fracturing has gained positive effect and formed commensurable comprehensive reservoir evaluation technique and mating engineering technique of hydraulic fracturing. The main cognitions and achievements are as follows: 1.Study of geological information such as lithololy analysis and nuclear magnetic logging, etc, indicates that clay carbonate formation of Shu-Lu cave is anisotropic, low permeable with high shale content, whose accumulation space gives priority to microcracks. 2.The analysis of lithomechanics of clay carbonate indicates that the hardness is moderate, Young’s modulus is between that of sandstone and limestone, clay carbonate presents plastic property and its breakdown pressure is high because of the deep buried depth. 3.The analysis of the drillstem test curves indicates that the flow and build-up pressure curve of clay carbonate of Shu-Lu cave mainly has three types: formation contamination block-up type, low permeable type, formation energy accumulation slowness type; the reservoir characteristics presents double porosity media, radial compounding, uniform flow vertical fracture, isotropy, moniliform reservoir type. The target well Jingu 3 belongs to moniliform reservoir type. 4.Through recognition and re-evaluation of the treatment effect and technologic limitations of acidizing, acid fracturing and gelled acidizing in the past, based on the sufficient survey and study of hydraulic fracturing home and abroad, combined with comprehensive formation study of target well, we launched the study of the optimization of hydraulic fracturing technique, forming the principal clue and commensurable mating technology aimed at clay carbonate formation, whose targets are preventing leak off, preventing sand bridge, preventing embedment, controlling fracture height, forming long fracture. 5. Recognition of stimulation effect evaluation.

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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.

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In this thesis, detailed studies on the sedimentology and petrophysical properties of reservoir rocks in the Shan#2 Member of Shanxi Formation, Zizhou gas field of Ordos Basin, are carried out, based on outcrop description, core description, wireline log interpretation and analysis of petrophysical properties. In the context of stratigraphic division scheme of the Upper Paleozoic in Ordos Basin, the Shan#2 Member is further divided into three subintervals: the Shan#23, Shan#22 and Shan#21, based on the marker beds,depositional cycles, wireline log patterns. Subaqueous deltaic-front distributary channels, distributed from the south to north, is identified,which is the main reservoir sand bodies for gases of Shan#2 Member at Zizhou gas field. Quartzose and lithic-quartzose sandstones, commonly with a high volume of cement, but a low volume of matrix, are the major reservoir rocks in the studied area. All sandstones have been evolved into the late diagenetic stage (referred to as diagenetic stage B) during the burial, experiencing compaction, cementation, replacement and dissolution, in which the compaction and cementation could have reduced the porosity, while dissolution could have improved the petrophysical properties. The pore types in the reservoirs are dominated by intergranular-solutional, intergranular-intercrystal and intercrystal-solutional porosity. According to the parameters and capillary pressure curves of test samples, five types of pore texture (I-V) are differentiated, in which types II and III pore textures displayed by low threshold pressure-wide pore throat and moderate threshold pressure-moderately wide pore throat, exist widespread. Sandstone reservoirs in the studied area are characterized by exceptionally low porosity and permeability, in which the petrophysical properties of those in Shan#23 horizon are relatively better. The petrophysical property of reservoirs was influenced both by the sedimentation and diagenesis. In general, the coarse quartzose sandstones deposited in subaqueous distributary channels show the best petrophysical property, which tends to be worse as the grain size decreases and lithic amount increases. Three types of gas reservoirs in Shan#23 horizon are classified according to petrophysical properties (porosity and permeability), which could have been influenced by the initial depositional facies, diagenesis and tectonics. On the basis of the study on the geological conditions of reservoirs in the area, it is concluded that sedimetary facies, diagenesis and tectonic actions can provide an important foundation for gas pool formation, which can also control the accumulation and distribution of gas reservoirs.

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The Huade Group, consisting of low-grade and un-metamorphosed sedimentary rocks with no volcanic interlayer, is located at the northern margin of the North China craton and adjoining the south part of the Central Asian Orogenic Belt. It is east to the Paleo- to Meso-Proterozoic Bayan Obo and Zhaertai-Langshan rifts and northwest to the Paleo- to Neo-proterozoic Yanshan aulacogen, in which the typical Changcheng, Jixian and Qingbaikou systems are developed. The Huade Group are mainly composed of pebbly sandstones, sandstones, greywackes,shales,calc-silicate rocks and limestones, partly undergoing low-grade metamorphism and being changed to meta-sandstones, schists, phyllites, slates and crystalline limestones or marbles. The stratigraphic sequences show several cycles of deposition. Each of them developed coarse clastic rocks – interbedded fine clastic rocks and pelites from bottom upward or from coarse clastic rocks to interbedded fine clastic rocks and pelites to carbonate rocks. The Tumen Group outcrop sporadically around or west to the Tanlu faults in western Shandong. They are mainly composed of pebbly sandstones, sandstones, shales and limestones. This thesis deals with the characteristics of petrology, geochemistry and sedimentary of the Huade Group and the Tumen Group, and discusses the LA-ICP-MS and SIMS U-Pb ages, Hf isotope and trace element composition of the detrital zircons from 5 meta-sandstone samples of the Huade Group and 3 sandstone samples of the Tumen Group. The age populations of the detrital zircons from the Huade Group are mainly ~2.5 Ga and ~1.85 Ga, and there are also minor peaks at ~2.0 Ga, ~1.92 Ga and ~1.73 Ga. Most of the detrital zircon grains of 2.47-2.57 Ga and a few of 1.63-2.03 Ga have Hf crust model ages of 2.7-3.0 Ga, and most of the detrital zircon grains of 1.63-2.03 Ga have Hf crust model ages of 2.35-2.7 Ga, with a peak at 2.54 Ga. The main age peaks of the detrital zircons from the Tumen Group are ~2.5 Ga、~1.85 Ga, 1.57 Ga, 1.5 Ga, 1.33 Ga and 1.2 Ga. Different samples from the Tumen Group have distinct Hf isotopic characteristics. Detrital zircon grains of ~2.52 Ga from one sandstone sample have 2.7-3.2 Ga Hf crust model ages, whereas zircon grains of 1.73-2.02 Ga and 2.31-2.68 Ga from another sample have Hf crust model ages of 2.95-3.55 Ga. Detrital zircon grains of Mesoproterozoic ages have Paleoproterozoic (1.7-2.25 Ga) crust model ages. Through detailed analyses of the detrital zircons from the Huade and Tumen Group and comparison with those from the sedimentary rocks of similar sedimentary ages, the thesis mainly reaches the following conclusions: 1. The youngest age peaks of the detrital zircons of 1.73 Ga constrains the sedimentary time of the Huade Group from late Paleoproterozoic to Mesoproterozoic. 2. The age peaks of detrital zircons of the Huade Group correspond to the significant Precambrian tectonic-thermal events of the North China craton. The basement of the North China craton is the main provenance of the Huade Group, of which the intermediate to high grade metamorphic sedimentary rocks are dominant and provide mainly 1.85-1.92 Ga sediments. 3. The Huade basin belongs to the North China craton and it is suggested that the northern boundary of the North China craton should be north to the Huade basin. 4. The stratigraphic characteristics indicate the Huade Group formed in a stable shallow-hypabyssal sedimentary basin. The rock association and sedimentary time of the Huade Group are similar to those of the Banyan Obo Group and the Zhaertai Group, and they commonly constitute late Paleoproterozoic to Mesoproterozoic continental margin basins along the northern margin of the North China craton. 5. The continental margin basins would have initiated coeval with the Yanshan and Xiong’er aulacogens. 6. The ages of the detrital zircons from the Tumen Group and the Penglai Group at Shandong peninsula and the Yushulazi Group at south Liaoning are similar, so their sedimentary time is suggested to be Neoproterozoic,coeval with the Qingbaikou system. The detrital zircon ages of 1.0-1.2 Ga from the Tumen Group, the Penglai Group and the Yushulazi Group indicate that there have being 1.0-1.2 Ga magmatic activities at the eastern margin of the North China craton. 7. The U-Pb age populations of the detrital zircons from the late Paleoproterozoic to Neoproterozoic sedimentary rocks suggest that the main Precambrian tectonic-thermal events of the North China craton happened at ~2.5 Ga and ~1.85 Ga. But the events at 2.7 Ga and 1.2 Ga are also of great significance. Hf isotope characteristics indicate that the significant crust growth periods of the North China craton are 2.7-3.0 Ga and ~2.5 Ga.

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Migration carriers act as the “Bridges” connecting source rock and traps and play important roles in petroleum migration and accumulation system. Among various types of carriers, sandstone carrier constitutes the basis of carrier system consisting of connected sandstone bodies, of sand-bodies connected with other carriers, such as faults and/or unconformities. How do we understand sandstone carrier beyond the traditional reservoirs concept? How could we characterize quantitatively this kind of carriers for petroleum migration? Such subjects are important and difficult contents in dynamic studies on hydrocarbon migration and accumulation. Sandstone carrier of Chang 8 member in Longdong area of Ordos Basin is selected as the research target in this thesis. Through conducting integrated reservoir analysis on many single wells, the correlation between single sandstone thickness and oil thickness seems good. Sketch sandstone is defined in this thesis as the principal part of carrier based on systematical analysis on lithology and sandstone thickness. Geometry connectivity of sandstone bodies was identified by the spatial superposition among them and was proved by the oil property features in oilfields. The connectivity between sandstone carriers is also hydrodynamically studied by observing and analyzed various diagenetic phenomena, especially the authigenic minerals and their forming sequence. The results were used to characterize transporting capability of sandstone carriers during the key petroleum migration periods. It was found that compaction and cementation are main causes to reduce pore space, and resolution may but not so importantly increases pore space after the occurrence of first migration. The cements of ferrocalcite and kiesel seem like the efficient index to demonstrate the hydraulic connection among sandy bodies. Diagenetic sequence and its relationship with petroleum migration phases are analyzed. Sandstone carrier of Chang 8 member was then characterized by studying their pore space and permeable properties. The results show an average porosity and permeability of Chang 8 carriers are respectively 8% and 0.50md, belongs to low porosity - low permeability reservoirs. Further, the physical properties of Chang 81 member are commonly better than those of Chang 82 member. Methods to reconstruct property of sandstone carrier during petroleum migration phase (late Jurassic) are built based on diagenetic sequence. Planal porosity, porosity and permeability of sandstone carrier in this period are statistically analyzed. One combining index - product of thickness and ancient porosity - is selected as the idea parameter to characterize sandstone carrier of late Jurassic after contrast with other parameters. Reservoirs of Chang 8 member in Longdong area are lithological reservoir controlled by sand body in which oil layers in middle part are clamped with dry layers in upper and lower parts, in a sandwich way. Based a newly proposed “migration-diagensis-remigration” model in low permeability sandstone of Chang 8 member in Longdong area, oil migration and accumulation processes during different periods are simulated with the reconstructed sandstone carriers system. Results match well with current reservoir distributions. Finally, suggestions for next favorable exploration areas are given based on all research achievements.

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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.

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Nowadays, with the development of reservoir exploration, the method of exploration is growing. Together with well information and laboratory results, seismic information with high quality can predict reservoir successfully. Hydrocarbon Indicator is a method, which picks the most sensitive rock properties of hydrocarbons, scans the aim area with rock physics tools, and then indicates the area of reservoir. Obviously, the more is the difference between brine and oil/gas, the better this method works. Which parameter can be used as the Optimal Hydrocarbon Indicators is still in discussion. The author introduced several kinds of Hydrocarbon Indicators in this thesis. After analyzing the response of different parameter to reservoir, together with seismic information, the reservoir can be predicted. In this paper, the reservoir of Zhunge’er is studied to prove this kind of method is suitable for real exploration in China. Besides, the author chose Haila’er reservoir to testify whether this method could be used in metamorphic reservoir other than sandstone reservoir. The results highlighted the meaning of Optimal Hydrocarbon Indicators on reservoir identification. The author also mentioned some thoughts for the development of hydrocarbon indicators in the future.

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In order to carry out high-precision three-dimensional "integration" for the characteristics of the secondary seismic exploration for Biyang Depression, in the implementation process, through a combination of scientific research and production, summed up high-precision seismic acquisition, processing and interpretation technologies suitable for the eastern part of the old liberated areas, achieved the following results: 1. high-precision complex three-dimensional seismic exploration technology series suitable for shallow depression Biyang block group. To highlight the shallow seismic signal, apply goal-based observing system design, trail from the small panel to receive and protect the shallow treatment of a range of technologies; to explain the use of three-dimensional visualization and coherent combination of full-body three-dimensional fine interpretation identification of the 50-100 m below the unconformity surface and its formation of about 10 meters of the distribution of small faults and improve the small block and stratigraphic unconformity traps recognition. 2. high-precision series of three-dimensional seismic exploration technology suitable for deep depression Biyang low signal to noise ratio of information. Binding model using forward and lighting technology, wide-angle observation system covering the design, multiple suppression and raise the energy of deep seismic reflection processing and interpretation of detailed, comprehensive reservoir description, such as research and technology, identified a number of different types of traps. 3. high-precision seismic exploration technology series for the southern Biyang Depression high steep three-dimensional structure. The use of new technology of seismic wave scattering theory and high-precision velocity model based on pre-stack time migration and depth migration imaging of seismic data and other high-precision processing technology, in order to identify the southern steep slope of the local structure prediction and analysis of sandstone bedrock surface patterns provide a wealth of information.

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Reservoir prediction techniques from prestack seismic are among the most important ones for exploration of lithologic hydrocarbon reservoir. In this paper, we set the turbidite fan sandstone reservoir in Liao-Zhong depress as our researching target, and aims to solve the apllication difficulties on pre-stack inversion in the area, where the drilling data is scarce and the reservoir is lateral varied. Meanwhile, AVO analysis and pre-stack inversion for gas-bearing detection is systematically researched. The seismic reflection characters of gas-bearing sandstone in turbidite fan with different fluid content are defined, after analyzing results from AVO seismic simulation and porous fluid replacement of real log data, and under the guides of the seismic characters from classical gas-bearing sandstone reservoir and numerical simulation for complicate gas-bearing sandstone. It is confirmed that detecting gas-bearing sandstone in turbidite fan via AVO technologies is feasible. In terms of AVO analysis, two AVO characters, fluid detection factor and product of intercept and gradient, can effectively identify top and bottom boundaries and lateral range of tuibidite gas sand by comparing real drilling data. Cross-plotting of near and far angle stack data could avoid the correlation existing in P-G analysis. After comparing the acoustic impedance inversions with routine stacked data and AVO intercept, impedance derived from AVO intercept attribute could reduce the acoustic impedance estimating error which is caused by AVO. On the aspect of elastic impedance inversion, the AVO information in the pre-stack gathers is properly reserved by creating partial angle stack data. By the far angle elastic impedance alone, the gas sand, with abnormally low range of values, can be identified from the background rocks. The boundary of gas sand can also be clearly determined by cross-plotting of near and far angle elastic impedances. The accuracy of far angle elastic impedance is very sensitive to the parameter K, and by taking the statistical average of Vp/Vs on the targeted section in key wells, the accuracy of low frequency trends is gurranteed; the intensive absorsion within the area of the gas sand, which tends to push the spectral of seismic data to the lower end, will cause errors on the inversion result of elastic impedance. The solution is to confine the inversion on the interested area by improving the wavelet. On the aspect of prestack AVA simultaneous inversion, the constraint of local rock-physical trends between velocities of P-wave、S-wave and density successfully removes the instability of inversion, thus improves the precision of the resulting elastic parameters. Plenty of data on rock properties are derived via AVO analysis and prestack seismic data inversion. Based on them, the fluid anomaly is analysized and lithological interpretation are conducted. The distribution of gas sand can be consistently determined via various of ways, such as cross-plotting of P and G attributes, near and far partial angle stack data, near and far angle elastic impedances, λρ and Vp/Vs, etc. The shear modulo and density are also reliable enough to be used for lithological interpretation. We successfully applied the AVO analysis and pre-stack inversion techniques to gas detecting for turbidite fan sand reservoir in Liao-Zhong depression.

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Sedimentary provenance direction,sedimentary facies,reservoir geological characteristic,pore structure; physical property characteristic,reservoir classification and evaluation ,forthermore,favorable area area are forecasted of Yanchang formation in ZhiDan region, by mainly study on the data of field section observation ,core observation, well logging explaination and routine microscope slice identification,scanning Electron Microscope and reservoir analysis of lithology and physical property , Under the guidance of such advanced theories and methods as sedimentology,reservoir sedimentology,lithological oil pool and so on,in the thesis. The following fruits are mainly achieved in this paper: Yanchang formation stratum is divided and correlated in this entire region, and the characteristic of oil layer unit is detailed discussed , respectively. According to main marker bed and supplementary ones.and research result shows that the source of provenance direction during Yanchang Formation mianly is north-east. Delta and lake are mainly developed in study area ,sub-facies and micro-facies are divided,distribution of sedimentary micro-facies in plane and palaeogeographic evolution are described,and gentle slope type- shallow water delta depositional model is established. Fine-grain arkose sandstone is the main reservoir,and which have experienced such different degree diagenesis as compaction, cementation, replacement and dissolution, and in which compaction and cementation are mainly factors to reduce sandstone physical property and dissolution effectively improved physical property during burial diagenesis procedure. All reservoirs of Yanchang Formation have entered A period of late diagenetic stage according to scheme of diagenesis period division . Intergranular porosity,dissolution porosity,fissure porosity are main pore types. And porosity structure are analyse by mercury penetration capillary pressure parameter,fine-shortness type and fine- length throat type are mainly developed. as a whole,the reservoir, with the characteristic of porosity and permeability altering apparently,strong inhomogeneity , is a medium- porosity and medium permeability one. In plane,higher- porosity and higher-permeability are corresponded well with distributary channel area, physical property and inhomogeneity are affected by both deposition and diagenesis,and distributary channel and underwater distributary channel are favorable facies . According to such characteristic as lithology,physical property,pore structure ,diagenesis and sandstone distribution, the sandy reservoir can be classified 4 types, and the main sandy in every oil layer unit are evaluated according to the standard. The analysis result of petroleum concentration rule shows that Yanchang Formation are with not only favourable oil source rock,reservoir,covering combination ,but also good entrapment condition in study area. Lithology and structure-lithology oil pool are mainly developed ,based on condition of favorable reservoir developments,accounting for deliverability and sandstone superface elevation,zone of profitabilitis are forecasted.

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Lower member of the lower Ganchaigou Formation in the southwestern of Qaidam Basin is one of the main targeted exploration zones. With the advancement of exploration, the targets are gradually switching into the lithologic reservoirs and it is urgent to gain the more precise research results in distribution of sedimentary facies and sandstones. Guided by the theory of sequence stratigraphy and sedimentology as well as on the basis of many logging data, drillings, seismic data and chemical tests, the paper comprehensively analyzes the sedimentary facies and sandstones in the lower member of lower Ganchaigou Formation in the southern of Chaixi. According to the identification marks of the key interface in sequence stratigraphy, the key interfaces in lower member of lower Ganchaigou Formation in the southwestern of Qaidam Basin are identified as two third-order sequences SQ1、SQ2. By calibrating the synthetic seismogram, the seismic sequence, well drilling and logging sequences are united. Based on the works above, this paper chooses seven primary cross-sections and builds connecting-well stratigraphic correlation of seven main connecting-well sections. Ultimately, the high-resolution sequence stratigraphic frameworks in the lower member of the lower Ganchaigou Formation, which are uniform to logging and seismic data, are figured out. In terms of study on each sequence features, the main style of the base-level cycle overlay which forms the third-order sequence is confirmed. It contains asymmetric “becoming deep upward” style and symmetry style. Researching on the spreading characters of sequence stratigraphy indicates that SQ1 and SQ2 are rather thicker near northwest well Shashen 20 and Shaxin1 while they are quite thiner near Hongcan 1, Yuejin, Qie 4 and Dong8-Wu3, and the thickness of SQ1 is thicker than SQ2.Based on the deep analysis of the marks for depositional facies, it is proposed that the lake facies and braid river deltas facies mainly occurred in study areas. Besides, the sorts of sub-facies and micro-facies model are divided and described. Under the control of high-resolution sequence stratigraphic framework, three source directions from Arlarer Mountain、Qimantage Mountain and Dongchai Mountain are identified by using the features of heavy mineral assemblage and paleogeomorphy. In addition, regularities of distribution sedimentary facies in sequence stratigraphic framework are studied in accordance with research thinking of the "point" (single well) "line" (section) "face" (plane). In the stage of lower member in the lower Ganchaigou Formation in the southwestern of Qaidam Basin, it is at the early phrase of evolution of the lake basin with the gradual outspread and the rise of the lake level. Combined with physical analysis of reservoir sands formed in different sedimentary environment, the paper studies the style of favorable sandstone bodies that are underwater distributary channel of braided rive delta front, coarse sand in mouth bar and the sand body in sand flat of shore-shallow lacustrine facies. Finally, this article comprehensively analyzes the distribution relationship between sedimentary facies and favorable sandstone body and proposes the ideas that sequence SQ1 Yuejin area, well east 8-wu3 area, well qie4-qie1 area and well hongcan2 area are distributed areas of favorable sandstone.

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Tethyan Himalayan Sequence (THS) is located at the frontier of the India-Asia collision zone, which can preserve critical information about collision. This paper reports detailed petrology, geochemistry, spinels electron microprobe data, and in situ U-Pb ages and Lu-Hf isotopic data on detrital zircons from the late Cretaceous to early Eocene strata in Gyantze and Gamba area, south Tibet that provide important constraints on the early tectonic evolution of the India-Asia collision. In Gyantze, the lithic arkose in Zongzhuo mélange is characterized by, SiO2 =80.4%, Al2O3=8.6%, Na2O=1.6%, K2O=1.1%, LaN/YbN=8.90, and εNd (0) =-10.27. Spinels compositions are characterized by low TiO2 (generally <0.1%) and a Cr number mainly between 70 and 80. The largest population of detrital zircons is within the 73-169Ma range with high εHf (t) and > 500 Ma with complex εHf (t) values. The lithic arkose in Rilang conglomerate is characterized by, SiO2 =56.5%, Al2O3=15.6%, Na2O=4.7%, K2O=0.6%, LaN/YbN=5.00-5.29, and εNd (0) =1.92. Spinels of 2006T98 display high TiO2 (generally >0.2%) and a Cr number mainly between 70 and 85, other spinels are characterized by low TiO2 (generally <0.2%) and a Cr number mainly between 60 and 90. The largest population of detrital zircons is within 90-146 Ma range with high εHf (t). The lithic arkose in Jiachala formation is characterized by, SiO2 =64.6%, Al2O3=12.1%, Na2O=1.9%, K2O=1.8%, LaN/YbN=7.73-9.13, and εNd (0) =-5.52~-8.43. Spinels in the Jiachala formation have low TiO2 (generally <0.2%) and a Cr number between 39 and 88. Detrital zircons have a wide range of age distribution of 82-3165Ma with complex εHf (t). In Gamba, The quartze sandstone in Jidula formation is characterized by, SiO2=97.4%, Al2O3=0.9%, Na2O=0.03%, K2O=0.18%, LaN/YbN=18.70-21.684, and εNd (0) between -13.1~-7.4. While the lithic arkose in Zhepure formation is characterized by, SiO2=68.4%, Al2O3=7.3%, Na2O=1.15%, K2O=0.52%, LaN/YbN=6.09-8.99, and εNd(0)=-5.8~-6.3. Based on our geochemical analysis, spinles electron microprobe data, U–Pb ages and Hf isotope data for detrital zircons of the late Cretaceous-Eocene strata in Gyantze and Gamba, southern Tibet, the following major conclusions can be drawn: 1. In Gyantze, the Zongzhuo mélange was mainly derived from accretionary prism/THS of continental slop and Gangdese arc. Rilang conglomerate was totally from Gangdese arc. The Jiachala formation was derived from THS, suture zone and Gangdese arc. 2. In Gamba, the Jidula formation was from India craton, while the Zhepure formation was derived from THS, suture zone and Gangdese arc. 3. The deposite of Zongzhuo mélange and Rilang conglomerate (73-55Ma) marks the collision between India and Asia. 4. Late Paleocene-Eocene tectonic evolution is consistent with foreland basin system.