黄土中主要温室气体组分特征

Scientists have paid much attention to the greenhouse effects and the greenhouse gases for the fact of global warming. There are many uncertainties in the prediction of future climatic change. One of the important reasons causing the uncertainties is insufficient researches of the sources and sinks of greenhouse gases, especially, there is a missing sink in the global carbon cycle. The recent researches proposal that there may be an important carbon sink in the middle-latitude terrestrial ecosystems (vegetation and soil) in the North Hemisphere, despite that there is much disputation about its position and amplitude. Chinese loess is located in the middle latitude area in the North Hemisphere, what kind of role does it play in and how does it influence on the balance of the global greenhouse gases budget? For this reason, many samples were taken and analyzed from wide range and multi-stratum of Chinese loess to understand characteristics of major greenhouse gases in loess and loess possible effect on global greenhouse gas budget. Using self-made spiral corer, we totally took 81 gas samples and 65 soil samples from 7 loess profiles in China such as Zhaitang loess section of Beijing, Pianguan, Xingxian, Lishi, Puxian, Jishan loess section of Shanxi Province, and Luochuan loess section of Shaanxi Province. The gas concentrations for CO_2, CH_4 and N_2O, the contents of N_2, O_2 and carbonate, and the carbon isotopic compositions of CO_2 and carbonate in loess strata sequences are observed and measured. In addition, 19 gas samples data of the Weinan loess section, Shaanxi Province are combination with this research to study characteristics of greenhouse gases in loess. This research indicates that (1) the free gases in loess are neither paleo-atmospheric gases nor modern atmospheric gases; (2) the concentrations of CO_2, CH_4 and N_2O in loess are higher than atmospheric level; (3) the δ~(13)C of loess CO_2 shows that the CO_2 in loess mainly comes from the oxygenolysis of organic matters, but because of isotopic exchange with carbonate in loess, the carbon isotopic exchange with carbonate in loess, the carbon isotopic compositions of loess CO_2 are much more heavier than organic original CO_2; (4) the concentration of CH_4 in Malan loess is lower because it is not favorable for the decomposition of anaerobic bacteria in the Malan Loess; (5) estimation of the total amount of the carbonate in loess reveals that loess is a huge carbon reservoir (about 850PgC). In addition, the impact of the deuterogenic carbonatization during the loess accumulation on the global carbon cycle was discussed, and the preliminary conclusion is that the research work is still not enough to evaluate the effect of loess on the sources and sinks of the anthropogenic CO_2.

沾化凹陷火成岩油气藏形成条件和分布规律研究

As a kind of special lithologic ones, Igneous rock oil and gas pool is more and more paid attention, and it has different forming condition and distribution from conventional ones, such as various terrane distribution types, serious reservoir anisotropy, complicated hydrocarbon-bearing, so there is not successful experience to follow for exploration and development of this complex subtle oil and gas pool at present. For an example of Igneous oil and gas pool of Luo151 area in Zhanhua seg, Eastern China, this article study the difficult problem, including petrologic nd lithofacies analysis, Origin, invasion age and times of Igneous rock, reservoir anisotropy, Geological Modeling, Igneous reservoir synthesis evaluation. forming condition and distribution are studied synthetically, and an integrated method to predict igneous rock oil and gas pool is formed, which is evaluated by using development data. The Igneous rock is mainly diabase construction in Luo151 area of Zhanhua Sag, and petrologic types include carbonaceous slate, hornfels, and diabases. Based on analyzing synthetically petrologic component, texture and construct, 4 lithofacies zones, such as carbonaceous slate subfacies, hornfels subfacies containing cordierite and grammite, border subfacies and central subfacies, are divided in the diabase and wall rock. By studying on isotopic chronology, terrane configuration and imaging logging data, the diabase intrusion in Zhanhua Sag is formed by tholeiite magma emplacing in Shahejie formation stratum on the rift tension background Lower Tertiary in North China. The diabase intrusion of Luo151 is composed possibly of three periods magma emplacement. There is serious anisotropy in the diabase reservoirs of Luo151 in Zhanhua Sag. Fracture is primary reservoir space, which dominated by tensile fracture in high obliquity, and the fracture zones are mainly developed round joint belt of igneous rock and wall rock and position of terrane thickness changing rapidly. The generation materials of the reservoirs in Luo151 igneous oil pools consist of Intergranular micropore hornfels, condensate blowhole-solution void diabase condensate edge, the edge and center of the condensate seam diabase, of which are divided into horizontal, vertical and reticulated cracks according fracture occurrence. Based on the above research, a conceptual model of igneous rock reservoir is generated, which is vertically divided into 4 belts and horizontally 3 areas. It is built for the first time that classification evaluation pattern of igneous rock reservoir in this area, and 3 key wells are evaluated. The diabase construction is divided into grammite hornfels micropore type and diabase porous-fracture type reservoirs. The heavy mudstone layers in Third Member of Shahejie formation (Es3) provide favorable hydrocarbon source rock and cap formation, diabase and hornfels belts serve as reservoirs, faults and microcracks in the wall rocks as type pathways for oil and gas migration. The time of diabase invasion was about in the later deposition period of Dongying Formation and the middle of that of Guantao Formation, the oil generated from oil source rock of Es3 in the period of the Minghuazhen formation and is earlier more than the period of diabase oil trap and porous space forming. Based on geological and seismic data, the horizon of igneous rocks is demarcated accurately by using VSP and synthetic seismogram, and the shape distribution and continuity of igneous rocks are determined by using cross-hole seismic technology. The reservoir capability is predicted by using logging constraining inversion and neural network technology. An integrated method to predict igneous rock oil and gas pool is formed. The study is appraised by using development data. The result show the reservoir conceptual model can guide the exploration and development of oil pool, and the integrated method yielded marked results in the production.

博兴洼陷西部砂体成因与油气成藏研究

Based on achievements of thirty years of hydrocarbon exploration, this paper uses the modern theories and methods of sedimentology and oil accumulation to study the origin and distribution features of four sandbodies of Gaoqing, Fanjia, Zhenglizhuang and Jinjia from the third member to the lower second member of Shahejie Formation in detail. Various geophysical methods are also used to explain and to predict the spatial distribution of sandbodies, which further shows mechanism and the model of oil accumulation and illuminates the disciplinarians of oil enrichment and its controlling factors in the study area. The most favourable oil pools predicted by this paper have significant economic and social benefits, which has been confirmed by the exploration. The main conclusions and knowledge includes: (1) Resolving the problems, which remain unresolvable for a long time in the western area of Boxing depression, about the original environment and the spatial distribution of sandbodies of Gaoqing, Fanjia, Zhenglizhuang and Jinjia, and illuminating their relationships. It is suggested that two deltas or delta-related sandbody sediments, which include the delta sandbodies of Jinjia and Gaoqing and their frontal turbidite fan sandbody, are developed in the second and third members of Shahejie Formation. The sandbodies of Fanjia, Gaoqing and Zhenglizhuang are components of Gaoqing delta and belong to the sediments of various periods in different part of the delta. Whereas, the sandbody of Jinjia belong to the Jinjia delta or fan-delta created by the uplift of the Western Shandong and in some areas shows the features of juxtaposition, superimposed deposition and fingeration with the sandbodies of Gaoqing and Zhenglizhuang. (2)Proposing that the sandbodies of different origins in the deltas of Gaoqing and Jinjia have obvious different reservoir qualities, among which the delta frontal bedded sandbodies in the second member of Shahejie Formation in Zhenglizhuang are the best ones and the turbidite sandbody of Fanjia is relatively worse. This shows the direction of further reservoir prediction. (3) According to modern petroleum system theory and continental pool-formation theory, the author divided the western area of Boxing depression into the Jinjia—Zhenglizhuang—Fanjia nose structure belt pool-formation system and the Gaoqing fracture belt pool-formation system. The study area is predominantly located in the former belt and subdivided into pool-formation sub-systems of Zhenglizhuang-Fanjia and Jinjia, which have the source rock of mudstone and oil shale from the upper forth member and the third member of Shahejie Formation in Boxing depression. The hydrocarbon migration and accumulation are controlled by Jinjia-Zhenglizhuang-fanjia nose structure and Gaoqing fracture. (4)Proposing that compared with the best developed sandbodies and traps in the west area of Boxing, the source from the Boxing depression is not sufficient, which is the fundamental reason that the hydrocarbon resources in mid-west area is less than in the east of Boxing. (5) Under the direction of the new theory (fluid compartments theory) and new method of modern pool-formation mechanism, two kinds of pool-formation model are established in study, i.e. inner-compartment model and outer-compartment model. The former has abnormal pressure and is the antigenic source seal pool-forming mechanism, whereas the latter has normal pressure and is of the allochthonous source opening pool-formation mechanism. (6)The study shows that the four sandbodies of Gaoqing, Fanjia, Jinjia and Zhenglizhuang sand are all very benefit for pool-formation, among which the Fanjia sandbody is the best favourable one and is likely to form lithological reservoir and fault-lithological reservoir. But the main step of exploration in Gaoqing, Zhenglizhuang sandbodies should be finding out the fault block, reversed roof and stratum-lithological oil reservoir. (7)Established a set of guidelines and techniques for the research and exploration in the large scale of sandbodies. Proposing that the various traps related to reversed fault and basin-ward fault should be found in step slopes and gentle slopes respectively, and the lithological oil reservoir should mainly be found in the sandstone updip pinch out. It is also suggested that Fanjia sandbody is most favourable to form the lithological and fault-lithological and the Gaoqing, Zhenglizhuang and Jinjia sandbodies have the potential of forming fault block, reversed roof and stratum-lithological oil reservoir. (8) Interpretation and prediction the spatial distribution of main sandbodies based on various geophysical methods suggestion that Fanxi, Gao28 south and Gao27 east have better exploration potential.

东营凹陷北部陡坡带砂砾岩体性油气藏形成机理及分布规律研究

The north steep slope zone of Dongying Depression has great potential in oil resource and as the usage of 3-d seismic data in the last decade, the exploration of oil and gas has get into the stage of sandy glavel body lithological oil-gas pool exploration. In this thesis, writer take the north steep slope zone of Dongying Depression as target area and take Sha-III and Sha-[V Menber as purpose stratum, study on sequence stratigraphy, depositional system, reservoir description, emphasesing on analyzing of forming of lithological oil-gas pool, especially the dynamics principle of oil and gas preliminary movement from the source rock to the reservoir form lithological oil-gas pools. The aim of this work is to give some quantitatively explanation for the mechanism of lithological oil-gas pool forming, and set up the theory of pool form with characteristic terrestrial faulted basin. There are main conclusions and views as follow. 1. Applying with principle of sequence stratigrapgy, according to the depositional cycles of Dongying Depression, the sequence stratigraphical partition of Tertiary was finished, stressing on dismembering Sha-III and Sha-IV Menber as 5system tracts. 2. The structure of Dongying Depression especially of the north steep slope zone has accomplished, including the analyzing the structural cortroling to depositional condition of the north steep slope zone of Dongying Depression, discussed relationship between the structure of the north steep slope zone and the pool-forming. 3. The horizontal and vertical exchanges of ancient climates and ancient physiognomy of the all stratum units and studies on characteristic of depositional system distribution have been finished, found that there are five depositional systems in the north steep slope zone of Dongying Depression as fluvial, delta (tan-delta), sub-water fluvial fan lacustrine, gravitive flow, and seven formations of sandy glavel body, and forecasting of all kinds of sandy glavel body has been made. 4. Seismic stratigraphy and log stratigraphy have been made, described and forecasted all kinds of reservoir of objective stratum by means of physical geography method, setup a series means of sandy glavel body description suit to target area. 5. The pool-forming system has been studied, analyzing all the elements in petroleum sub-system of Sha-III and Sha-IV Menber of Dongying Depression with view of source controlling, estimated the petroleum system applying source rock potential index combining with distribution ofreservior. 6.Through studying types of pool, the controlling factors of pool-forming of sandy glavel body were discussed by deposition stages, formation types, structure ect. as a conclusion that the characteristics of pool forming in the north steep slope zone of Dongying Depression are, the controlling factor of the pools is mainly lithology, petrophysics of oil sands vary greatly, with a large heterogeneity, all kind of reservoir with different formation has different pool-forming conditions, and as a result, formed various pools of sandy glavel body along the steep slope with regular combination, distribution and constituted the multiple petroleum accumulative pattern. 7. It's the first time to cauculate and estimate the fluid pressure in source rock of Dongying Depression, set up the stratum fluid pressure in Dongying Depression, and firstly use equivalent charging pressure and reservoir forming index to quantitatively evaluate the pool-forming condition of lithological pool.8. Above all studies, follow up the scent of the exploration combined with practice a lot of explorative targets were found, and got geat economic and social benefit.

沾化凹陷泥质岩油气藏成藏特征研究

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.

地震波场延拓+菲涅尔体叠加方法及成像效果

In the increasingly enlarged exploration target, deep target layer(especially for the reservoir of lava) is a potential exploration area. As well known, the reflective energy becomes weak because the seismic signals of reflection in deep layer are absorbed and attenuate by upper layer. Caustics and multi-values traveltime in wavefield are aroused by the complexity of stratum. The ratio of signal to noise is not high and the fold numbers are finite(no more than 30). All the factors above affect the validity of conventional processing methods. So the high S/N section of stack can't always be got with the conventional stack methods even if the prestack depth migration is used. So it is inevitable to develop another kind of stack method instead. In the last a few years, the differential solution of wave equation was hold up by the condition of computation. Kirchhoff integral method rose in the initial stages of the ninetieth decade of last century. But there exist severe problems in it, which is are too difficult to resolve, so new method of stack is required for the oil and gas exploration. It is natural to think about upgrading the traditionally physic base of seismic exploration methods and improving those widely used techniques of stack. On the other hand, great progress is depended on the improvement in the wave differential equation prestack depth migration. The algorithm of wavefield continuation in it is utilized. In combination with the wavefield extrapolation and the Fresnel zone stack, new stack method is carried out It is well known that the seismic wavefield observed on surface comes from Fresnel zone physically, and doesn't comes from the same reflection points only. As to the more complex reflection in deep layer, it is difficult to describe the relationship between the reflective interface and the travel time. Extrapolation is used to eliminate caustic and simplify the expression of travel time. So the image quality is enhanced by Fresnel zone stack in target. Based on wave equation, high-frequency ray solution and its character are given to clarify theoretical foundation of the method. The hyperbolic and parabolic travel time of the reflection in layer media are presented in expression of matrix with paraxial ray theory. Because the reflective wave field mainly comes from the Fresnel Zone, thereby the conception of Fresnel Zone is explained. The matrix expression of Fresnel zone and projected Fresnel zone are given in sequence. With geometrical optics, the relationship between object point in model and image point in image space is built for the complex subsurface. The travel time formula of reflective point in the nonuniform media is deduced. Also the formula of reflective segment of zero-offset and nonzero offset section is provided. For convenient application, the interface model of subsurface and curve surface derived from conventional stacks DMO stack and prestack depth migration are analyzed, and the problem of these methods was pointed out in aspects of using data. Arc was put forward to describe the subsurface, thereby the amount of data to stack enlarged in Fresnel Zone. Based on the formula of hyperbolic travel time, the steps of implementation and the flow of Fresnel Zone stack were provided. The computation of three model data shows that the method of Fresnel Zone stack can enhance the signal energy and the ratio of signal to noise effectively. Practical data in Xui Jia Wei Zhi, a area in Daqing oilfield, was processed with this method. The processing results showed that the ability in increasing S/N ratio and enhancing the continuity of weak events as well as confirming the deep configuration of volcanic reservoir is better than others. In deeper target layer, there exists caustic caused by the complex media overburden and the great variation of velocity. Travel time of reflection can't be exactly described by the formula of travel time. Extrapolation is bring forward to resolve the questions above. With the combination of the phase operator and differential operator, extrapolating operator adaptable to the variation of lateral velocity is provided. With this method, seismic records were extrapolated from surface to any different deptlis below. Wave aberration and caustic caused by the inhomogenous layer overburden were eliminated and multi-value curve was transformed into the curve.of single value. The computation of Marmousi shows that it is feasible. Wave field continuation extends the Fresnel Zone stack's application.

准噶尔盆地吉木萨尔凹陷含油气系统形成与分布研究

On the basis of the theory and method of petroleum system, by using formation analysis and multi-discipline ways, we study the formation and .distribution of petroleum system of the Jimusaer sag in the Zhungaer Basin. Through analysis and description of main formation factors, petroleum system is classified and subdivided into several ranks. At the same time, we describe the main elements of reservoir formation and the contribution to the petroleum system. By analyzing the process of reservoir formation, we define the quantitative relationship of petroleum sources, migration and oil accumulation. Through a comprehensive studying method, the next step is to build the reservoir formation model of petroleum system and confirm the exploration target. Finally, a method which fits to study the petroleum system formation and distribution in this type of basin is created. It broadens the quantitative theory of petroleum system. The following are the main conclusions. 1. The division of rank concept of petroleum system and the classification of multi-ranks combination are put forwarded for the first time. The petroleum system is classified into 5 ranks. These ranks, in an ascending order, are compounded petroleum system, independent petroleum system, sub-petroleum system, reservoir formation structure and the main factors of reservoir formation respectively. Therefore the Jimusaer sag is divided into 1 first ranked compounded petroleum system, 2 independent petroleum systems (The first is Jiang first member ~ Jiang second member+Pingdiquan member+ Wutonggou member petroleum system and the second Pingdiquan member - Wutonggou member+Triassic + Jurassic petroleum system) and 22 sub- petroleum systems. 2. The existence of the Jiangjunmiao member petroleum system in P_1 is put forwarded for the first time in the target zone except for Pingdiquan member hydro-source rock in P2 Both two hydro-source rock experience two evolvement movements, sub-mature and mature. It is estimated that there is the matured oil&gas in the sag. 3. By introduction of the basin simulation method, regaining and formation process of the different independent petroleum system are achieved. The sources, migration, accumulation and evolution rule are all indicated. It proposed that Jiang first member ~ Jiang second member+Pingdiquan member + Wutonggou member petroleum system formed primarily in Triassic and Jurassic. The oil&gas predominantly accumulated in layers of Jiang second member and Wutonggou member. Pingdiquan member ~ Wutonggou member+Triassic + Jurassic petroleum system formed in middle of Jurassic, and middle and late of the Kreaceous. In addition the oil&gas mostly accumulated in layers of Pingdiquan member and Wutonggou member. 4. By comprehensively analyzing the reservoir formation mechanism, it is proposed that oil&gas reservoir in this zone is formed in multiple periods. Major migration and accumulation power of oil&gas can be explained by an abnormal stratum pressure. There are six channels for the migration and accumulation -of oil&gas and therefore, can be considered as multi-circular distribution. 5. Combining the rank theory of petroleum system with mode identification method, we developed a quantitative evaluation method and judgment system for the exploration target. Using this technique, we confirmed three exploration target zones, four favorable oil&gas reservoir combinations, three exploration wells. Ji -15 well has been drilled and has provided a breakthrough on the oil&gas exploration.

东营凹陷沙三中亚段湖相浊积岩储层特征及油气成藏规律研究

Turbidity sandstone reservoirs have been an important field of hydrocarbon exploration and development in the basins all over the world, as well as in China. Lithologic pools are composed of turbidity sandstones and other sandstones are frequently found in the Jiyang Depression that is a Mesozoic-Cenozoic non-marine oil-bearing basin. The Dongying Sag lies in the sedimentary center of the basin. The subtle traps with turbidity reservoirs are generally difficult to be predicted and described by using current techniques. The studies on turbidity reservoirs plays thus an important theoretical and theoretical practical role in exploration and development in the Jiyang Depression. The attention is, in this thesis, focused on the petrologic properties and oil accumulating behaviors in lake turbidity sedimentary systems in the middle part of the third section of Shahejie Formation in the Dongying Sag, especially in Dongxin area, which lies on the central uplift of the Sag. The paper has disclosed the origin types of turbidity sandstones, distribution pattern and controlling factors of turbidity sandstones, and set up hydrocarbon accumulation patterns of the middle part of the third section of Shahejie Formation in Dongxin, based on nonmarine high resolution sequence stratigraphy, event sedimentology and new theories of hydrocarbon forming. By studying prediction method and technology of turbidity sandstone reservoirs, using precise geological model developing, new techniques of high resolution seismic inversion constrained by logging, the paper has forecast low permeability turbidity sandstone reservoirs and pointed out advantage exploration aims to progressive exploration and development. The paper has obtained mainly many productions and acknowledges as follows: 1.Turbidity sandstone reservoirs of the third section of Shahejie Formationin Dongying Sag are formed in such specifical geological background as rift and extension of basin. The inherited Dongying delta and transgression make up many turbidity distribution areas by overlaying and joining together. The hydrocarbon migrates from depression area to adjacent turbidity sandstone continuously. Accumulation area which is sufficient in oil is formed. 2.The paper has confirmed distinguishable sign of sequence boundary , established stratigraphic framework of Dongying Sag and realized isotime stratigraphic correlation. Es3 of Dongying delta is divided into eleven stages. Among them, the second period of the lower section in Es3, the sixth period of the middle section in Es3, the third period of the upper section in Es3 correspond to eleven sedimentary isotime surface in seismic profile, namely Es3 is classified into eleven Formations. 3.According to such the features of turbidity sandstone as deep in burial, small in area, strong in subtle property, overlaying and joining together and occurring in groups, management through fault and space variations of restriction quantum are realized and the forecast precision of turbidity sandstone by using precise geological model developing, new techniques of high resolution seismic inversion constrained by logging, based on the analysis of all kinds of interwell seismic inversion techniques. 4.According to the features of low permeable turbidity sandstone reservoirs, new method of log interpretation model is put forward. At the same time, distinguish technology of familiar low resistivity oil layer in the turbidity sandstone reservoirs is studied based on petrophysical laboratory work and "four properties" interrelationship between lithological physical Jogging and bearing hydrocarbon properties. Log interpretation model and reservoir index interpretation model of low resistivity oil layer are set up. So the log interpretation precision is improved. 5.The evolution law and its difference of the turbidity sandstone are embodies as follows: the source of sediments come from the south and east of the study area in the middle period of Es3. East source of sediments is pushed from west to east. However, the south source supply of sediments in the early and middle period of Es3 is in full, especially in Es3. subsequently, the supply is decreased gradually. Turbidity fan moves back toward the south and the size of fan is minished accordingly. The characteristic of turbidity sandstone in Dongying Sag is different in different structural positions. Dongxin in the middle-east of the central lift and Niuzhuang Sag He in Dongying delta front and prodelta deep lake subfacies. Although the turbidity sandstone of the two areas root in the Dongying delta sedimentary system, the sand body has different remarkably characteristic. 6.The sedimentary model of the turbiditys in study area have three types as follows: (1) collapse turbidity fan in respect of delta; (2) fault trench turbidity fan; (3) other types of microturbidity sandstone. Middle fan and outer fan, can be found mainly in sublacustrine fan. Middle fan includes braided channel microfacies, central microfacies and braided interchannel microfacies, which is main prospecting oil-bearing subfacies. The middle section of the third section of Shahejie Formation in study area (for example the central lift) can be divided into middle-lower and upper part. The middle-lower part is characteristic of turbidity fan. The upper part is sedimented mainly by delta-collapse fan. 7.The turbidity reservoirs of the middle part of the third section of Shahejie Formation in study area characterize by low maturity both in component and texture, strong in diagenesis and low in permeability. The reservoir can be classified into four types. Type III is the body of reservoir and comprises two types of H a and HI b. M a belongs to middle porosity - low permeability reservoir and distributes in the central lift. Hlb belongs to low porosity - low permeability and distributes in Haojia region. 8.A11 single sand body of lens turbidity reservoir of the middle part of the third section of Shahejie Formation in study area are surrounded by thick dark source rocks. The oil-water system is complex and behaves that every sandstone is single seal unit. The water body is 1/3-1-5 of the sand body. The edge water is not active. The gas exists in the top of reservoir in the form of mixed gas. For far-range turbidity fan with big scale channel, the area and volume of sand body is large and the gap is big in oil packing degree. There are lots of edge water and bottom water, and the latter increases rapidly during the course of development. 9.By exerting the modern hydrocarbon forming theories, the third section of Shahejie Formation in study area belongs to abnormally pressured fluid compartment. The lithological reservoir of the third section of Shahejie Formation is formed in the compartment. The reservoir-formed dynamic system belongs to lower self-source enclosed type. The result and the practice indicate that the form and accumulation of lithological oil reservoirs are controlled by the temperature and pressure of stratum, microfacies, thickness of sand body, fault and reservoir heterogeneity. 10. Based on studies above, the emphases focus on in south and north part of Dongying structure, west Dongxin region and south part Xinzhen structure in the application of production. The practice proves that the turbidity sandstone reservoirs in Ying 11 block and the fault-lithological reservoirs in Xin 133 block have been obtained significant breakthrough. The next target is still sandstone groups of the third section of Shahejie Formation in the bordering areas of Dongxin region for instance Xin 149 area, He 89 area, Ying 8 area etc.

陆相砂泥岩层序的高精度检测方法研究及应用

Ordos Basin is a typical cratonic petroliferous basin with 40 oil-gas bearing bed sets. It is featured as stable multicycle sedimentation, gentle formation, and less structures. The reservoir beds in Upper Paleozoic and Mesozoicare are mainly low density, low permeability, strong lateral change, and strong vertical heterogeneous. The well-known Loess Plateau in the southern area and Maowusu Desert, Kubuqi Desert and Ordos Grasslands in the northern area cover the basin, so seismic data acquisition in this area is very difficult and the data often takes on inadequate precision, strong interference, low signal-noise ratio, and low resolution. Because of the complicated condition of the surface and the underground, it is very difficult to distinguish the thin beds and study the land facies high-resolution lithologic sequence stratigraphy according to routine seismic profile. Therefore, a method, which have clearly physical significance, based on advanced mathematical physics theory and algorithmic and can improve the precision of the detection on the thin sand-peat interbed configurations of land facies, is in demand to put forward.Generalized S Transform (GST) processing method provides a new method of phase space analysis for seismic data. Compared with wavelet transform, both of them have very good localization characteristics; however, directly related to the Fourier spectra, GST has clearer physical significance, moreover, GST adopts a technology to best approach seismic wavelets and transforms the seismic data into time-scale domain, and breaks through the limit of the fixed wavelet in S transform, so GST has extensive adaptability. Based on tracing the development of the ideas and theories from wavelet transform, S transform to GST, we studied how to improve the precision of the detection on the thin stratum by GST.Noise has strong influence on sequence detecting in GST, especially in the low signal-noise ratio data. We studied the distribution rule of colored noise in GST domain, and proposed a technology to distinguish the signal and noise in GST domain. We discussed two types of noises: white noise and red noise, in which noise satisfy statistical autoregression model. For these two model, the noise-signal detection technology based on GST all get good result. It proved that the GST domain noise-signal detection technology could be used to real seismic data, and could effectively avoid noise influence on seismic sequence detecting.On the seismic profile after GST processing, high amplitude energy intensive zone, schollen, strip and lentoid dead zone and disarray zone maybe represent specifically geologic meanings according to given geologic background. Using seismic sequence detection profile and combining other seismic interpretation technologies, we can elaborate depict the shape of palaeo-geomorphology, effectively estimate sand stretch, distinguish sedimentary facies, determine target area, and directly guide oil-gas exploration.In the lateral reservoir prediction in XF oilfield of Ordos Basin, it played very important role in the estimation of sand stretch that the study of palaeo-geomorphology of Triassic System and the partition of inner sequence of the stratum group. According to the high-resolution seismic profile after GST processing, we pointed out that the C8 Member of Yanchang Formation in DZ area and C8 Member in BM area are the same deposit. It provided the foundation for getting 430 million tons predicting reserves and unite building 3 million tons off-take potential.In tackling key problem study for SLG gas-field, according to the high-resolution seismic sequence profile, we determined that the deposit direction of H8 member is approximately N-S or NNE-SS W. Using the seismic sequence profile, combining with layer-level profile, we can interpret the shape of entrenched stream. The sunken lenticle indicates the high-energy stream channel, which has stronger hydropower. By this way we drew out three high-energy stream channels' outline, and determined the target areas for exploitation. Finding high-energy braided river by high-resolution sequence processing is the key technology in SLG area.In ZZ area, we studied the distribution of the main reservoir bed-S23, which is shallow delta thin sand bed, by GST processing. From the seismic sequence profile, we discovered that the schollen thick sand beds are only local distributed, and most of them are distributary channel sand and distributary bar deposit. Then we determined that the S23 sand deposit direction is NW-SE in west, N-S in central and NE-SW in east. The high detecting seismic sequence interpretation profiles have been tested by 14 wells, 2 wells mismatch and the coincidence rate is 85.7%. Based on the profiles we suggested 3 predicted wells, one well (Yu54) completed and the other two is still drilling. The completed on Is coincident with the forecastThe paper testified that GST is a effective technology to get high- resolution seismic sequence profile, compartmentalize deposit microfacies, confirm strike direction of sandstone and make sure of the distribution range of oil-gas bearing sandstone, and is the gordian technique for the exploration of lithologic gas-oil pool in complicated areas.