102 resultados para Oil pollution of soils


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In this paper, the complex faulted-block oil reservoir of Xinzhen area in Dongying depression is systematically studied from basic conditions forming faulted-block oil and gas reservoir integrating geology, seismic, logging and reservoir engineering information and computer; guided by petroleum geology, geomechanics, structural geology and geophysics and other theories. Based on analysis of background condition such as regional strata, structure and petroleum geology, structural research on geometry, kinemaitcs and dynamics, oil-controlling fault research on the seal features, sealing mechanism and sealing pattern, and research on enrichment rules and controlling factors of complex faulted-block oil reservoir are carried out to give out the formation mechanics of oil reservoir of Xinzhen complex faulted-block oil reservoir. As a result, the reservoir formation pattern is established. At the same time, through dissecting the characteristics and hydrocarbon enrichment law of complex faulted-block oil reservoir, and studying its distribution law of remaining oil after entering extra high water-cut period, a set of technologies are formed to predict complex faulted-block oil reservoir and its remaining oil distribution and to enhance oil recovery (EOR). Based on the time relationship between migration of hydrocarbon and trap formation, accumulating period of Xinzhen oil reservoir is determined. The formation of Xinzhen anticlinal trap was prior to the primary migration. This is favorable to formation of Xinzhen anticlinal hydrocarbon reservoir. Meanwhile, because anticline top caving isn't at the sane time as that of moving or faulted-trap forming inner anticline, oil and gas migrated many times and Xinzhen complex faulted-block oil reservoir formed from ES_3~(upper) to EG. Accumulating law and controlling factors of complex faulted-block reservoir are analyzed from many aspects such as regional structure background controlling hydrocarbon accumulating, plastic arch-open structure controlling oil-bearing series and reservoir types, sealing-opening of fault controlling hydrocarbon distribution and structure pattern controlling enriched trap types. Also, we established the structure pattern in Xinzhen a'ea: the arch-open of underlying strata cause expanding fracture. The main block groups developed here are shovel-like normal fault block group in the north area of Xinzhen and its associated graben block group. Block groups dominate the formation and distribution of reservoirs. We studied qualitatively and quantitatively the sealing characteristics, sealing history and sealing mechanism of faults, too. And, the sealing characteristics are evaluated and the distribution pattern of hydrocarbon controlled by faults is researched. Due to movement intensity of big faults, deep falling of downthrown block, high degree of repture and development of fracture, shallow layers close to the downthrown block of secondary faults are unfavorable to hydrocarbon accumulation. This is confirmed by the exploration practice in Xinzhen anticline. In terms of the downthrown blocks of sencondary contemporaneous faults lied in the south and north area of Xinzhen, hydrocarbon is poor close to fracture belt, while it is relatively abundant in tertiary companion faults. Because of long-term movement of faults that control hydrocarbon, fi'om ES3 to EG, six set of oil-bearing series formed. And their opening causes the inhomogeneity in hydrocarbon abundance among each block--in two flanks of anticline reservoirs are abundant while in the axial area, oil and gas are sporadic. There the sealing characteristics control oil-bearing area of oil/gas accumulation and the height of oil reservoir. Longitudinally, oil and gas are enriched in dip-flat areas in mid-plane of faults. It is established that there are four types of accumulating patterns in complex faulted-block oil reservoirs in Xinzhen. The first is accumulating pattern of lithologic oil reservoirs in E~S_3~(mid-lowwer), that is, self-generating-self-reserving-self-covering lithologic trap pattern. The second is drag-anticline accumulating pattern in Xinzhen. The structure traps are drag anticlines formed by the contemporaneous faults of the second basement in the north of Xinzhen, and the multiple source rocks involve Ek_2, Es_4, Es_3 and Es_1 members. The reservoirs are fluvial-delta sandstones of the upper member of Shahejie formation and Guantao formation, covered by regional thick mudstone of the upper member of Guantao formation and MingHuazhen formation. The third is the accumulating pattern of reverse listric fault, the third-degree fault of Xinzhen anticline limb and the reservoirs form reservoir screened by reverse listric faults. The forth is accumulating pattern of crossing faults which form closing or semi-closing faulted-blocks that accumulate hydrocarbon. The technologies of predicting remaining oil in complex faulted-block reservoir during the mid and late development stage is formed. Remaining oil in simple large faulted-blocks enriches in structural high, structural middle, structural low of thick bottom water reservoirs, points near bent edge-fault oftertiary faults and part the fourth ones with big falling displacement, microstructure high place of oil-sandbodies and areas where local well pattern isn't perfect. While that in small complex faulted-blocks enriches near small nose, small high point, angle of small faults, small oil-bearing faulted-blocks without well and areas with non-perfect well pattern. The technologies of enhancing recovery factor in complex faulted-block reservoir during the mid and late development stage is formed as follows: fine reservoir description, drilling adjust wells, designing directional wells, sub-dividing layer series of development, improving flooding pattern, changing water-injection direction and enhancing swept volume, cyclic waterflooding and gas-injection, etc. Here, directional wells include directional deflecting wells, lateral-drilling wells, lateral-drilling horizontal wells and horizontal wells. The results of this paper have been used in exploration and development of Shengli oilfield, and have achieved great social and economic profit, especially in predicting distribution of complex faulted-block reservoir, remaining oil distribution during middle and late stage of development, and in EOR. Applying the achievement of fault-closure research, new hydrocarbon-bearing blocks are discovered in flanks of Dongying central uplift and in complex blocks with proved reserves 15 million tons. With the study of remaining oil distribution law in complex faulted-block reservoirs, recovery factors are increased greatly in Dongxin, Xianhe and Linpan complex faulted-block reservoirs and accumulated oil production increment is 3 million tons.

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Mudstone reservoir is a subtle reservoir with extremely inhomogeneous, whose formation is greatly related to the existence of fracture. For this kind of reservoir, mudstone is oil source rock, cover rock and reservoir strata, reservoir type is various, attitude of oil layer changes greatly, and the distribution of oil and gas is different from igneous or clastic rock reservoir as well as from carbonate reservoir of self-producing and self-containing of oil and gas. No mature experience has been obtained in the description, exploration and development of the reservoir by far. Taking Zhanhua depression as an example, we studied in this thesis the tectonic evolution, deposit characteristics, diagenesis, hydrocarbon formation, abnormal formation pressure, forming of fissure in mudstone reservoir, etc. on the basis of core analysis, physical simulation, numerical simulation, integrated study of well logging and geophysical data, and systematically analyzed the developing and distributing of mudstone fissure reservoir and set up a geological model for the formation of mudstone fissure reservoir, and predicted possible fractural zone in studied area. Mudstone reservoir mainly distributed on the thrown side of sedimentary fault along the sloping area of the petroleum generatiion depression in Zhanhua depression. Growing fault controlled subsidence and sedimentation. Both the rate of subsidence and thickness of mudstone are great on the thrown side of growing fault, which result in the formation of surpressure in the area. The unlocking of fault which leads to the pressure discharges and the upward conduct of below stratum, also makes for the surpressure in mudstone. In Zhanhua depression, mudstone reservior mainly developed in sub-compacted stratum in the third segment of Shahejie formation, which is the best oil source rock because of its wide spread in distribution, great in thickness, and rich in organic matter, and rock types of which are oil source mudstone and shale of deep water or semi-deep water sediment in lacustrine facies. It revealed from core analysis that the stratum is rich in limestone, and consists of lamina of dark mudstone and that of light grey limestone alternately, such rock assemblage is in favor of high pressure and fracture in the process of hydrocarbon generation. Fracture of mudstone in the third segment of Shahejie formation was divided into structure fracture, hydrocarbon generation fracture and compound fracture and six secondary types of fracture for the fist time according to the cause of their formation in the thesis. Structural fracture is formed by tectonic movement such as fold or fault, which develops mainly near the faults, especially in the protrude area and the edge of faults, such fracture has obvious directivity, and tend to have more width and extension in length and obvious direction, and was developed periodically, discontinuously in time and successively as the result of multi-tectonic movement in studied area. Hydrocarbon generation fracture was formed in the process of hydrocarbon generation, the fracture is numerous in number and extensively in distribution, but the scale of it is always small and belongs to microfracture. The compound fracture is the result of both tectonic movement and hydrocarbon forming process. The combination of above fractures in time and space forms the three dimension reservoir space network of mudstone, which satellites with abnormal pressure zone in plane distribution and relates to sedimentary faces, rock combination, organic content, structural evolution, and high pressure, etc.. In Zhanhua depression, the mudstone of third segment in shahejie formation corresponds with a set of seismic reflection with better continuous. When mudstone containing oil and gas of abnormal high pressure, the seismic waveform would change as a result of absorb of oil and gas to the high-frequency composition of seismic reflection, and decrease of seismic reflection frequency resulted from the breakage of mudstone structure. The author solved the problem of mudstone reservoir predicting to some degree through the use of coherent data analysis in Zhanhua depression. Numerical modeling of basin has been used to simulate the ancient liquid pressure field in Zhanhua depression, to quantitative analysis the main controlling factor (such as uncompaction, tectonic movement, hydrocarbon generation) to surpressure in mudstone. Combined with factual geologic information and references, we analyzed the characteristic of basin evolution and factors influence the pressure field, and employed numerical modeling of liquid pressure evolution in 1-D and 2-D section, modeled and analyzed the forming and evolution of pressure in plane for main position in different periods, and made a conclusion that the main factors for surpressure in studied area are tectonic movement, uncompaction and hydrocarbon generation process. In Zhanhua depression, the valid fracture zone in mudstone was mainly formed in the last stage of Dongying movement, the mudstone in the third segment of Shahejie formation turn into fastigium for oil generation and migration in Guantao stage, and oil and gas were preserved since the end of the stage. Tectonic movement was weak after oil and gas to be preserved, and such made for the preserve of oil and gas. The forming of fractured mudstone reservoir can be divided into four different stages, i.e. deposition of muddy oil source rock, draining off water by compacting to producing hydrocarbon, forming of valid fracture and collecting of oil, forming of fracture reservoir. Combined with other regional geologic information, we predicted four prior mudstone fracture reservoirs, which measured 18km2 in area and 1200 X 104t in geological reserves.

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This article is an important part of "95" technological subject of SINOPEC. It has a large number of difficulties and workloads, and has significant theoretical meanings and practical value. The study area is composed of sandstone & conglomerate reservoir of alluvial fan & fan delta, which belong to Sha3 lower member and Sha4 upper member of lower tertiary of Yong'an Town Oilfield in Dongying Depression. The target stataum develops in the hanging wall of the synsedimentary fault in the scarp zone of Dongying Depression. The frequently intense movements result in the variation of sandstone and conglomerate reservoir and the evolution of the time and space of Sha3 lower member and Sha4 upper member in Yong'an Town Oilfield. As a result, it is difficult for the individual reservoir correlation at the root of fan, which bring about a tackle problem for the exploitation of oilfield. In this background, the research of fluid units will be more difficult. In this article, the new concepts, the new methods, and the new techniques of sedimentology, petroleum geology, reservoir geology, physics of crystal surface, dynamic & static state reservoir description and well logging geology are synthetically applied, and the computer technology are made full uses of, and the identifying, dividing and appraising of the two-formation-type sandstone & conglomerate reservoir fluid units of Sha3 lower member and Sha4 upper member systemically analyzed in Yong'an Town Oilfield, Dongying Depression. For the first time, the single-well model, the section model, the plane model, the nuclear magnetism log model, the microcosmic network model, the 4-D geology model and the simulation model of the two-formation-type reservoir fluid units of the of sandstone & conglomerate reservoir of Sha3 lower member and Sha4 upper member are established, and the formative mechanism and distributing & enrichment laws of oil-gas of the two type of sandstone and conglomerate reservoir fluid units are revealed. This article established the optimizing, identifying, classifying and appraising standard of the two-formation-type reservoir fluid units of the of sandstone and conglomerate reservoir of Sha3 lower member and Sha4 upper member, which settles the substantial foundations for static state model of the fluid units, reveals the macroscopic & microcosmic various laws of geometrical static state of the fluid units, and instructs the oil exploitation. This article established static state model of the two-formation-type sandstone and conglomerate reservoir fluid units by using the multi-subject theories, information and techniques, and reveals the geometrical configuration, special distribution and the oil-gas enrichment laws of the sandstone and conglomerate reservoir fluid units. For the first time, we established the nuclear magnetism log model of the two-formation-type sandstone and conglomerate reservoir of Sha3 lower member and Sha4 upper member, which reveals not only the character and distributing laws of the porosity and permeability, bat also the formation and distribution of the movable fluid. It established six type of microcosmic net model of the two-formation-type sandstone and conglomerate reservoir of Sha3 lower member and Sha4 upper member in the working area by using the advanced theories, such as rock thin section, SEM, image analysis, intrusive mercury, mold, rock C.T. measure & test image etc., which reveals the microcosmic characteristic of porosity & throat, filterate mode and microcosmic oil-gas enrichment laws of the sandstone and conglomerate reservoir. For the first time, it sets up the 4-D model and mathematic model of the sandstone and conglomerate reservoir, which reveals the distributing and evolving laws of macroscopic & microcosmic parameters of the two-formation-type sandstone and conglomerate reservoir and oil-gas in 4-D space. At the same time, it also forecasts the oil-gas distribution and instructs the oilfield exploitation. It established reservoir simulation model, which reveals the filterate character and distributing laws of oil-gas in different porosity & throat net models. This article established the assistant theories and techniques for researching, describing, indicating and forecasting the sandstone and conglomerate reservoir fluid units, and develops the theories and techniques of the land faces faulted basin exploitation geology. In instructing oilfield exploitation, it had won the notable economic & social benefits.

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The Grove Mountains, including 64 nunataks, is situated on an area about 3200km2 in the inland ice cap of east Antarctica in Princess Elizabeth land (72o20'-73°101S, 73°50'-75o40'E), between Zhongshan station and Dome A, about 450km away from Zhongshan station (69°22'S, 76°22'E). Many workers thought there was no pedogenesis in the areas because of the less precipitation and extreme lower temperature. However, during the austral summer in 1999-2000, the Chinaer 16 Antarctic expedition teams entered the inland East Antarctica and found three soil spots in the Southern Mount Harding, Grove Mountains, East Antarctica. It is the first case that soils are discovered in the inland in East Antarctica. Interestingly, the soils in this area show clay fraction migration, which is different from other cold desert soils. In addition, several moraine banks are discovered around the Mount Harding. The soil properties are discussed as below. Desert pavement commonly occurs on the three soil site surfaces, which is composed of pebbles and fragments formed slowly in typical desert zone. Many pebbles are subround and variegated. These pebbles are formed by abrasion caused by not only wind and wind selective transportation, but also salt weathering and thaw-freezing action on rocks. The wind blows the boulders and bedrocks with snow grains and small sands. This results in rock disintegration, paved on the soil surface, forming desert pavement, which protects the underground soil from wind-blow. The desert pavement is the typical feature in ice free zone in Antarctica. There developed desert varnish and ventifacts in this area. Rubification is a dominant process in cold desert Antarctic soils. In cold desert soils, rubification results in relatively high concentrations of Fed in soil profile. Stained depth increases progressively with time. The content of Fed is increasing up to surface in each profile. The reddish thin film is observed around the margin of mafic minerals such as biotite, hornblende, and magnetite in parent materials with the microscope analyzing on some soil profiles. So the Fed originates from the weathering of mafic minerals in soils. Accumulations of water-soluble salts, either as discrete horizons or dispersed within the soil, occur in the soil profiles, and the salt encrustations accumulate just beneath surface stones in this area. The results of X-ray diffraction analyses show that the crystalline salts consist of pentahydrite (MgSO4-5H2O), hexahydrite (MgSO4-6H2O), hurlbutite (CaBe2(PO4)2), bloedite (Na2Mg(S04)2-4H2O), et al., being mainly sulfate. The dominant cations in 1:5 soil-water extracts are Mg2+ and Na+, as well as Ca2+ and K+, while the dominant anion is SO42-, then NO3-, Cl- and HCO3-. There are white and yellowish sponge materials covered the stone underside surface, of which the main compounds are quartz (SiO2, 40.75%), rozenite (FeSOKkO, 37.39%), guyanaite (Cr2O3-1.5H2O, 9.30%), and starkeyite (MgSO4-4H2O, 12.56%). 4) The distribution of the clay fraction is related to the maximum content of moisture and salts. Clay fraction migration occurs in the soils, which is different from that of other cold desert soils. X-ray diffraction analyses show that the main clay minerals are illite, smectite, then illite-smectite, little kaolinite and veirniculite. Mica was changed to illite, even to vermiculite by hydration. Illite formed in the initial stage of weathering. The appearance of smectite suggests that it enriched in magnesium, but no strong eluviation, which belongs to cold and arid acid environment. 5) Three soil sites have different moisture. The effect moisture is in the form of little ice in site 1. There is no ice in site 2, and ice-cement horizon is 12 cm below the soil surface in site 3. Salt horizon is 5-10 cm up to the surface in Site 1 and Site 2, while about 26cm in site 3. The differentiation of the active layer and the permafrost are not distinct because of arid climate. The depth of active layer is about 10 cm in this area. Soils and Environment: On the basis of the characteristics of surface rocks, soil colors, horizon differentiation, salt in soils and soil depth, the soils age of the Grove Mountains is 0.5-3.5Ma. No remnants of glaciations are found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5Ma, and the ice cap was not much higher than present, even during the Last Glacial Maximum. The average altitude of the contact line of level of blue ice and outcrop is 2050m, and the altitude of soil area is 2160m. The relative height deviation is about 110m, so the soils have developed and preserved until today. The parental material of the soils originated from alluvial sedimentary of baserocks nearby. Sporepollen were extracted from the soils, arbor pollen grains are dominant by Pinus and Betula, as well as a small amount Quercus, Juglans, Tilia and Artemisia etc. Judging from the shape and colour, the sporepollen group is likely attributed to Neogene or Pliocene in age. This indicates that there had been a warm period during the Neogene in the Grove Mountains, East Antarctica.

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Aim at the variousness and complexity of the spatial distribution of Remaining Oil in the fluvial and delta facies reservoir in paper. For example, in the La-Sa-Xing oilfield of Daqing, based on the research of the control factor and formation mechanization of block, single layer, interlayer and micromechanism, synthesizing the theories and methods of geology, well logging, reservoir engineering, artificial intelligence, physical simulation test , and computer multidisciplinary; Fully utilizing the material of geology, well logging, core well, dynamic monitor of oil and water well, and experimental analysis, from macro to micro, from quality to quantity, from indoor to workplace, we predicted the potentiality and distribution according to the four levels of Block, single layer, interlayer and micromechanism, and comprehensively summarized the different distribution pattern of remaining oil in the fluvial and delta facies reservoir This paper puts forward an efficient method to predict the remaining recoverable reserves by using the water flooding characteristic curve differential method and neutral network; for the first time utilizes multilevel fuzzy comprehensive judgment method and expert neutral network technology to predict the remaining oil distribution in the single layer? comprehensively takes advantage of reservoir flowing unit, indoor physical simulation test, inspection well core analysis and well-logging watered-out layer interpretation to efficiently predict the distribution of remaining oil; makes use of core analysis of different periods and indoor water driving oil test to study the micro distribution of remaining oil and the parameters varying law of reservoir substance properties, rock properties, wetting properties. Based on above, the remaining oil distribution predicting software is developed, which contains four levels of block, single layer, interlayer and micromechanism. This achievement has been used inLa-Sa-Xing oil field of Daqing and good results have been received.

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This paper is belonging to Chinese Petrochemical Corporation's key project. Although it is difficult and great workload, it has important theoretical and practical value. Its targets is to establish 4 dimension stress fields of complex fault block groups, and then to predict the forming mechanism and distribution rule of petroleum pools, by applying the most advanced theories, methods and technology and the most sophisticated software in highly explored zones. By means of multi-discipline theories, methods, technologies and multi-source information, using computer with maximum efforts, investigating the strata framework, structure framework, petroleum pool forming mechanism and forming mode of complex fault block groups, several results have been achieved as following: The fastigiated mode of Xianhe complex fault block groups was established, pointed out the control function of pool accumulate in Xianhe complex fault block groups Xianhe fastigiated complex fault block groups are the results of combining stress of extending, slipping and reversing, which formed in early Shahejie stage, changed and perplexed during Dongying stage and that control the forming and destruction of petroleum pools. By measuring the earth stress and rock mechanics parameters in the research region, the model of 4 dimension stress field and potential fields of migrating fluids was established from ES3 stage to current, with their space distribution and time evolve and petroleum accumulate. The fault-sealing model in Xianhe complex fault block groups was established, which reveal the sealing mechanism of petroleum about control-fault, made for petroleum pool prediction in complex fault block. The petroleum pool forming mode and mechanism in complex fault block was established. Petroleum distribution were predicted in three stress inverse zones, and remaining oil were point out in the high points of 2 micro-structures and the region with strong fault-sealing capabilities. (6). A set of theories, technology and methods of complex fault block petroleum pool have been developed, bring on an improvement of the development geology theory in continental fault depression lake basin, good economic benefits have been obtained by applying on both east and west areas of our country.

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Based on the study of types, even temperature, the character of age-old fluid and fluid pressure of the reservoir fluid-inclusion in the Upper Paleozoic of Ordos Basin , combining with the diagenesis and character of gas geochemistry, reservoir sequence, cause of the low pressure reservoir formation and formation environment have been studied, the following knows are acquired: Abundant fluid-conclusions have developed in sandstone reservoir in Upper Paleozoic of Ordos Basin,and its kinds is numerous , also taking place some changes such as shrinking rock, cracking, stretching after formation. According to formation cause, fluid inclusion is divided into two types:successive and nonsuccessive inclusion. Nonsuccessive inclusion is further divided into brine inclusion, containing salt crystal inclusion, gaseity hydrocarbon conclusion and liquid hydrocarbon conclusion and so on. The gaseity hydrocarbon conclusion distributes at all the Basin, the liquid hydrocarbon conclusion mainly distributes at the East of Basin, and its two kinds of fluorescence color: blue and buff reflects at least two periods of oil filling and oil source of the different maturity. The study of diagenesis has indicated that five periods of diagenesis correspond to five periods inclusion's growth.The first and second period conclusions mainly distribute at the increasing margin of quartz, little amount and low even temperature, containing little gaseity hydrocarbon conclusion; The third and fourth conclusions are very rich, and having multiplicity forms, gaseity hydrocarbon conclusion of different facies, distributing at the increasing margin and crevice of quartz, its even temperature is between 85℃and 135℃;The fifth inclusion is relatively few ,mainly distributing at vein quartz and calcite, and developing few gaseity hydrocarbon conclusion. The fluid in the inclusion is mainly NaCl brine:low and high salinity brine fluid(containing salt crystal).The former salinity is between 0.18% and 18.55%,and mainly centralized distributing at three sectongs: from 0% to 4%, from 6% to 8%, from 10% to 14%, expressing that the alternation of the underground fluid was not intense, the conservation condition was good in different periods. The trapping pressure of the gaseity hydrocarbon conclusion calculated by PVTsim(V10)simulation is between 21.39 MPa and 42.58MPa,the average is 28.99MPa,mainlydistributes at between 24 MPa and 34MPa,and having a character of gradually lower from early to late time. The pressure of SuLiGe and WuShenQi dropped quickly in early time, and YuLin, ShenMu-MIZhi gas area dropped slowly in early and quickly in late time, ha portrait the change of trapping pressure can be divided into three old-age pressure systems: TaiYuan-ShanXi formation, low ShiHeZi formation and high ShiHeZi-ShiQianFeng formation. In plane, the trapping pressure dropped lowly from south to north in main reservoir period, and this reflects the gas migrating direction in the geohistory period. The analysis of gas component and monnmer hydrocarbon isotope indicates that the gas in Upper Paleozoic of Ordos Basin is coal-seam gas. The gas C_1-C_4 rnonnmer hydrocarbon isotopes has distinct differences in different stratums of different areas, and forming YuLin, SuLiGe and ShenMu-MIZhi three different distributing types. To sum up, gas reservoir combination in Upper Paleozoic of Ordos Basin can be divided into three sets of combination of reservoir formation: endogenesis type, near source type and farther source type,and near source gas combinations of reservoir formation is the main gas exploration area for its high gas filling intensity, large reservoir size.

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The Gangxi oil field has reached a stage of high water production. The reservoir parameters, such as reservoir physical characteristics, pore structure, fluid, have obviously changed. This thesis therefore carries out a study of these parameters that control reservoir characteristics, physical and chemical actions that have taken place within the reservoirs due to fluid injection, subsequent variations of reservoir macroscopic physical features, microscopic pore structures, seepages, and formation fluid properties. This study rebuilds a geologic model for this oil field, establishes a log-interpreting model, proposes a methodology for dealing with large pore channels and remnant oil distribution, and offers a basis for effective excavation of potential oil, recovery planning, and improvement of water-injection techniques. To resolve some concurrent key problems in the process of exploration of the Gangxi area, this thesis carries out a multidisciplinary research into reservoir geology, physical geography, reservoir engineering, and oil-water well testing. Taking sandstone and flow unit as objects, this study establishes a fine geologic model by a quantificational or semi-quantificational approach in order to understand the remnant oil distribution and the reservoir potential, and accordingly proposes a plan for further exploration. By rebuilding a geological model and applying reservoir-engineering methods, such as numerical simulation, this thesis studies the oil-water movement patterns and remnant-oil distribution, and further advances a deployment plan for the necessary adjustments and increase of recoverable reserves. Main achievements of this study are as follows: 1. The Minghazhen Formation in the Gangxi area is featured by medium-sinuosity river deposits, manifesting themselves as a transitional type between typical meandering and braided rivers. The main microfacies are products of main and branch channels, levee, inter-channel overflows and crevasse-splay floodplains. The Guantao Group is dominantly braided river deposit, and microfacies are mainly formed in channel bar, braided channel and overbank. Main lithofacies include conglomerate, sandstone, siltstone and shale, with sandstone facies being the principal type of the reservoir. 2. The reservoir flow unit of the Gangxi area can be divided into three types: Type I is a high-quality heterogeneous seepage unit, mainly distributed in main channel; Type II is a moderate-quality semi-heterogeneous seepage unit, mainly distributed in both main and branch channels, and partly seen within inter-channel overflow microfacies; Type III is a low-quality, relatively strong heterogeneous seepage unit, mainly distributed in inter-channel overflow microfacies and channel flanks. 3. Flow units and sedimentary microfacies have exerted relatively strong controls on the flowing of underground oil-water: (1) injection-production is often effective in the float units of Type I and II, whilst in the same group of injection-production wells, impellent velocity depends on flow unit types and injection-production spacing; (2) The injection-production of Type III flow unit between the injection-production wells of Type I and II flow units, however, are little effective; (3) there can form a seepage shield in composite channels between channels, leading to inefficient injection and production. 4. Mainly types of large-scale remnant-oil distribution are as follows: (1) remnant oil reservoir of Type III flow unit; (2) injection-production well group of remnant oil area of Type III flow unit; (3) remnant oil reservoirs that cannot be controlled by well network, including reservoir featured by injection without production, reservoir characterized by production without injection, and oil reservoir at which no well can arrive; (4) remnant oil area where injection-production system is not complete. 5. Utilizing different methods to deal with different sedimentary types, sub-dividing the columns of up to 900 wells into 76 chronostratigraphic units. Four transitional sandstone types are recognized, and contrast modes of different sandstone facies are summarized Analyzing in details the reservoirs of different quality by deciphering densely spaced well patterns, dividing microscopic facies and flow units, analyzing remnant oil distribution and its effect on injection-production pattern, and the heterogeneity. Theory foundation is therefore provided for further excavation of remnant oil. Re-evaluating well-log data. The understanding of water-flood layers and conductive formations in the Gangxi area have been considerably improved, and the original interpretations of 233 wells have changed by means of double checking. Variations of the reservoirs and the fluid and formation pressures after water injection are analyzed and summarized Studies are carried out of close elements of the reservoirs, fine reservoir types, oil-water distribution patterns, as well as factors controlling oil-gas enrichment. A static geological model and a prediction model of important tracts are established. Remaining recoverable reserves are calculated of all the oil wells and oil-sandstones. It is proposed that injection-production patterns of 348 oil-sandstones should be adjusted according to the analysis of adaptability of all kinds of sandstones in the injection-production wells.

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By applying multi-discipline theory and methods comprehensively and with full use of computer, the paper deeps into studying changing rule and control factor of fluid field of ES2 Shengtuo oil field during waterflood development, physical and chemical function, and stress. Matrix field, network field, fluid field, stress field and physical chemistry field and fluid model for dynamic function were established. Macroscopic and microscopic genesis mechanics, distribution rule and control factor of remaining oil were revealed. Remaining oil and emulate model were established. Macroscopic and microscopic distribution rule of mover remaining oil were predicted, several results were achieved as following: The distribution of remaining oil was controlled by micro-structure. At the same development stage, remaining oil saturation of the wells located in higher position of micro-structure is higher than the average saturation in the same layer. The water content ratio has same law. It is the enrichment district that the high position of micro-structure controlled by seal faults. The remaining oil distribution was affected by sedimentary micro-facies, micro-structure, fault sealing, reservoir heterogeneity and affusion-oil extraction. On the plane, the zone owning higher saturation of remaining oil is the area that at the edge miacro-facies and sand-body distribution discontinuously; on the section, the content of waterflood of the upper or middle-upper oil layer of positive rhythm and positive comprehensive rhythm is lower, middle and weak waterflood is main, remaining oil is in enrichment relatively. The remaining oil is relative enrichment at the zones of well network of affusion and oil extraction not affected. 4D dynamic model of reservoir of Es2in Shengtuo oil field was established. Macroscopic and microscopic forming mechanics, distribution rule and control factor were revealed. The emulate model of dynamic function of Shengtuo oil field was established, the space distribution of remaining oil were predicted. Reservoir flow field, matrix field, network field, seep field, physical and chemical field, stress field and fluid field models were established. Reservoir flow field character and distribution were revealed. An improvement of the development geology theory in continental fault depression continental basin was brought on.

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Through years of practice, reservoir management has already become the basic mode of foreign oil companies to realize the high-efficient development of the oil field. From the view of reservoir development and technological economy, reservoir management regards the study of the reservoir engineering, designs of reservoir projects and the dynamic analysis of the reservoir's performance as a system. In the fields of reservoir description, the establishment of the geological models and development models, the dynamic simulations of reservoir exploitation and the design of the oil engineering, reservoir management emphasizes the cooperation of the geology and the engineering, the combination of the engineering technology and the economic evaluation. In order to provide the means and basis for the reservoir geology study, reservoir evaluation, reserves calculation, numerical simulation, development plan and risk analysis, it adopts the reservoir management activities(team work) to make and implement the optimized oil field development management strategies so that secientific and democratic decision making can be achieved. Under the planned economic system for a long time, the purpose of Chinese reservoir development has been to fulfill the" mandatory" production task. With the deepening of the reform, the management organization of Chinese petroleum enterprises has been gradually going through the transition and reforms to the operational entity and the establishment of the mode of oil companies under the socialist market economy system. This research aims at introducing the advanced reservoir management technique from foreign countries to further improve the reservoir development results and wholly raise the economic benefits of Chinese mature land facieses sandstone reservoirs in the later stage of the water flooding. We are going to set up a set of modern reservoir management modes according to the reservoir features, current situation and existing problems of GangXi oil field of DaGang oil company. Through the study and implementation of the reservoir description and numerical simulation technology effectively, we plan to work out integrated adjustment projects, to study the related technology of oil recovery; to set up the effective confirmable data procedure and data management system of the reservoir management, to establish the coordinated model and workbench related to geology, engineering and economy in order to realize the real time supervision and evaluation on the process of reservoir development. We hope to stipulate modernization management tools for GangXi oil fields to rationally utilize various kinds of existing technological methods and to realize the economic exploitation and achieve the maximum benefits from the reservoir. The project of the modem reservoir management will be carried out on the GangXi oil field of DaGang oil company for this oil field is typical and has integrated foundamental materials and perfect networks. Besides, it is located in the good geographical position enjoying very convenient traffic. Implementing modern reservoir management will raise the recovery ratio, reduce the production cost and improve the working efficiency. Moreover, the popularization of modern reservoir management will improve the comprehensive benefits of DaGang oil company and even the whole Petro China. Through the reserch of this project, the following technical indicators can be reached: Establishing the concept of modern reservoir management. Establishing a set of integrated data information management system adapt to the features of GangXi reservoir. 3. Forming technical research modes of modern reservoir management suitable for mature reservoirs in the later developing stage. 4. Advancing projects of GangXi reservoir which are maxium optimized in engineering technique and economic benefits of oil exploitation. Besides, this set of technology, research principle and method can guide the mature reservoir of DaGang oil field and even the whole PetroChina to develop the further research of reservoir adjustment and improve the reservoir recovery factor and developing level constantly.

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Three soil spots were found in Grove Mountains, east Antarctica during 1999-2000, when the Chinare 16th Antarctic expedition teams entered the inland Antarctica. The characteristics of soils in Grove Mountains are desert pavement coating the surface, abundant water soluble salt, negligible organ matter, and severe rubification and salinization, scarces of liquid water, partly with dry permafrost, corresponding with the soils of McMurdo, Transantarctic. The soils age of Grove Mountains is 0.5-3.5Ma. Podzolization and redoximorphism are the main features in coastal Wilks region, in addition, there is strong enrichment of organic matter in many soils of this region. The main soil processes of Fildes Peninsula of King George Island include the intense physical weathering, decalcification and weakly biochemical processes. Peat accumulation is the main processes in Arctic because of humid and cold environment.Based on synthesis of heavy minerals, particle size, quartz grain surface textures, as well as pollen in soils, the soils parent materials of Grove Mountains derived from alluvial sediment of the weathering bedrocks around soils, and formed during the warm period of Pliocene. The detailed information is followed .l)The results of heavy minerals particle size showed the parent minerals derived form the weathering bedrocks around soils. 2)The quartz sand surface textures include glacial crushing and abrasion such as abrasive conchoidal fractures and grain edges, abrasive subparallel linear fractures and angularity, subaqueous environments produce V-shaped and irregular impact pits, polished surface, and chemical textures, such as beehive solution pits, which showed the water is the main force during the sediment of the soil parent minerals. 3)The pollen consist of 40 plant species, of which at least 5 species including Ranunculaceae, Chenopodiaceae, Artemisia, Gramineae, Podocarpus belong to the Neogene vegetation except the species from the old continent. Compared with Neogene vegetation of Transantarctic Mountains, Antarctic, we concluded that they grow in warm Pliocene.

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为了有效解决复杂断块带油气藏滚动勘探开发中的难点问题,论文在九五攻关项目“东濮凹陷油气藏发育机理研究”和中石化中原油田分公司重点项目“胡庆油田复杂断块带油气藏成藏条件与油气富集规律研究”等课题研究成果的基础上,结合当前国内外复杂断块带油气成藏机理研究的最新成果与先进的分析技术方法,以应力场分析为切入点,全面解剖东濮凹陷西斜坡断裂分布规律、油气藏形成过程、动力学特征与分布规律,以深化含油气系统研究在我国断陷盆地中的应用,为复杂断块带油气藏勘探和我国东部老油区的油气挖潜提供有效的分析方法和理论依据。并取得了6项创新性成果。