125 resultados para Airflow resistivity


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The effect of oxygen content on superconductivity of the 2212 and 2223 phase has been studied. By comparing the excess oxygen, the modulation vector, the XRD patterns, and the electric resistivity of 2212 and 2223 phase samples obtained with different post-annealing conditions, i.e., annealing at 600-degrees-C or quenching from 860-degrees-C, it was found that the superconductivity is markedly influenced by both the defect distribution in non-Bi layers and the interstitial oxygens incorporated in the Bi-O layers. A tentative explanation for this is given.

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New compounds LaSr2-xCa-(x)V3O9+/-y (x = 0.0, 0.67, 1.0, 1.33 and 2.0) have been synthesized with a simple new method X ray powder diffraction results indicate that they are single compound. Their lattice constants are calculated. The structure of LaSr2-xCa(x)V39+/-y changed from cubic to orthorhombic and back to cubic with the increase of calcium content. The results of weight gain in TG and XPS curves show that vanadium with lower valent state is oxidized to higher valent state at higher temperature. The oxygen content of new compounds are calculated from the weight gain. It is shown that V3+ and V4+ may coexist in LaSr2-xCa(x)V3O9+/-y. These compounds show that low resistivity.

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The electrical and magnetical properties of LaSr(2-x)Ca(x)V3O9 +/- y have been investigated. The compounds are antiferromagnetic. They show a metallic conduction other than semiconductivity. The trivalent and tetravalent vanadium ions coexist in the system. The magnetic susceptibility increases and the resistivity decreases at room temperature with the increase of x value. It is shown that the change of the valency state of vanadium obviously influences the electrical and magnetical properties of the system.

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The passive northern continental margin of the South China Sea is rich in gas hydrates, as inferred from the occurrence of bottom-simulating reflectors (BSR) and from well logging data at Ocean Drilling Program (ODP) drill sites. Nonetheless, BSRs on new 2D multichannel seismic reflection data from the area around the Dongsha Islands (the Dongsha Rise) are not ubiquitous. They are confined to complex diapiric structures and active fault zones located between the Dongsha Rise and the surrounding depressions, implying that gas hydrate occurrence is likewise limited to these areas. Most of the BSRs have low amplitude and are therefore not clearly recognizable. Acoustic impedance provides information on rock properties and has been used to estimate gas hydrate concentration. Gas hydrate-bearing sediments have acoustic impedance that is higher than that of the surrounding sediments devoid of hydrates. Based on well logging data, the relationship between acoustic impedance and porosity can be obtained by a linear regression, and the degree of gas hydrate saturation can be determined using Archie's equation. By applying these methods to multichannel seismic data and well logging data from the northern South China Sea, the gas hydrate concentration is found to be 3-25% of the pore space at ODP Site 1148 depending on sub-surface depth, and is estimated to be less than values of 5% estimated along seismic profile 0101. Our results suggest that saturation of gas hydrate in the northern South China Sea is higher than that estimated from well resistivity log data in the gas hydrate stability zone, but that free gas is scarce beneath this zone. It is probably the scarcity of free gas that is responsible for the low amplitudes of the BSRs.

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On the basis of analyzing the principle and realization of geo-steering drilling system, the key technologies and methods in it are systematically studied in this paper. In order to recognize lithology, distinguish stratum and track reservoirs, the techniques of MWD and data process about natural gamma, resistivity, inductive density and porosity are researched. The methods for pre-processing and standardizing MWD data and for converting geological data in directional and horizontal drilling are discussed, consequently the methods of data conversion between MD and TVD and those of formation description and adjacent well contrast are proposed. Researching the method of identifying sub-layer yields the techniques of single well explanation, multi-well evaluation and oil reservoir description. Using the extremum and variance clustering analysis realizes logging phase analysis and stratum subdivision and explanation, which provides a theoretical method and lays a technical basis for tracing oil reservoirs and achieving geo-steering drilling. Researching the technique for exploring the reservoir top with a holdup section provides a planning method of wellpath control scheme to trace oil and gas reservoir dynamically, which solves the problem of how to control well trajectory on condition that the layer’s TVD is uncertain. The control scheme and planning method of well path for meeting the demands of target hitting, soft landing and continuous steering respectively provide the technological guarantee to land safely and drill successfully for horizontal, extended-reach and multi-target wells. The integrative design and control technologies are researched based on geology, reservoir and drilling considering reservoir disclosing ratio as a primary index, and the methods for planning and control optimum wellpath under multi-target restriction, thus which lets the target wellpath lie the favorite position in oil reservoir during the process of geo-steering drilling. The BHA (bottomhole assembly) mechanical model is discussed using the finite element method, and the BHA design methods are given on the basis of mechanical analyses according to the shape of well trajectory and the characteristics of BHA’s structure and deformation. The methods for predicting the deflection rate of bent housing motors and designing their assemblies are proposed based on the principle of minimum potential energy, which can clearly show the relation between the BHA’s structure parameters and deflection rate, especially the key factors’ effect to the deflection rate. Moreover, the interaction model between bit and formation is discussed through the process of equivalent formation and equivalent bit considering the formation anisotropy and bit anisotropy on the basis of analyzing the influence factors of well trajectory. Accordingly, the inherence relationship among well trajectory, formation, bit and drilling direction is revealed, which lays the theory basis and technique for predicting and controlling well trajectory.

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So far, there is no methods of logging interpretation effective enough to identify a low resistivity payzone since its resistivity value almost equals to that of an aquifer although many low-resistivity payzones have been found in lots of petroliferous basins worldwide. After a thorough study on those technical difficulties of the logging interpretation for the low-resistivity payzones, some corresponding resolutions have been put forward in this paper. In order to reveal its microscopic mechanism, researches on the discovered low-resistivity payzones have been carried on with analyses of core and lab test data, thus main influencing factors of the low-resistivity reservoirs have been pointed out including conductivity minerals, clay minerals, fluids, porosity and pore structure. In order to make clear the degree of influence of those reservoir factors on resistivity logging(log), lab studies and numeral simulations have been done with the typical core and formation water samples, therefore, their influence degrees have ascertained quantitatively or semi-quantitatively. The distribution law and possible distribution areas of the low-resistivity payzones in Jiyang Depression have been figured out firstly after the macroscopic geology origins (sedimentation, dynamic accumulation process, diagenesis etc.) in the area have been studied. In order to resolve the problem of difficult logging-interpretation, methods of interpretation and identification have been brought forward creatively according to the low-resistivity payzone type ascribed to macroscopic geology laws and to the combined features of logging traces, after a systemic summary of different responses of logging caused by different microscopic mechanism. Those methods have been applied in Dongying and Huimin Sag of Shengli Exploration Area, precision of identification of the low-resistivity payzones improved effectively and good economic attraction prove their great prospect.

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In order to effectively identify and accurately evaluate low resistivity reservoir in Dongpu depression, using various logging data synthetically, geological and logging characteristics are summarized in term of different blocks on the basis of core analysis, cutting logging, oil testing and commissioning data. The formation mechanism of low resistivity reservoir is studied, and the main factors that cause low resistivity reservoir are discovered. The first factor is fine lithology, high shale content and hydrophilic rock. The second factor is high salinity formation water. The third factor is light oil, high gas quantity dissolved and large difference density of oil-water. The last factor is low amplitude structure of reservoir and low differential degree of oil-water. According to the characteristics of low resistivity reservoir, the method of compound lithology, the method of movable fluid, the method of phase permeability and the method of nuclear magnetic resonance logging are put forward. The compound lithology criterion of distinguishing hydrocarbon is founded in term of different blocks on the basis of electrical efficiency. The evaluation models of reservoir parameters are founded; whose core is oil saturation and phase permeability. In order to calculate oil saturation, the compound lithology model on the basis of electrical efficiency theory is chosen on condition that there is only the combination logging data of acoustic and induction; the W-S model is chosen on condition that there is all-around logging data. The calculational precision of oil saturation in low resistivity reservoir of work area is enhanced when the selection method is utilized. There are 1212 layers of reservoir newly added by the old well reexamination in the ten oil areas. The coincidence rate of logging interpretation reaches 83.2 percent according to the 74 well-times of oil testing or commissioning, which indicates that the distinguishing method and evaluation models of low resistivity reservoir above are feasible.By the reexamination, a ten million tons of proved reserves related to the low resistivity reservoir are newly added, consequently, the groundwork is established to increase reserve and production of old oilfields in the east of China and new livingness is added for the petroleum exploration and development in Dongpu depression.

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To extend the cross-hole seismic 2D data to outside 3D seismic data, reconstructing the low frequency data to high frequency data is necessary. Blind deconvolution method is a key technology. In this paper, an implementation of Blind deconvolution is introduced. And optimized precondition conjugate gradient method is used to improve the stability of the algorithm and reduce the computation. Then high-frequency retrieved Seismic data and the cross-hole seismic data is combined for constraint inversion. Real data processing proved the method is effective. To solve the problem that the seismic data resolution can’t meet the request of reservoir prediction in the river face thin-layers in Chinese eastern oil fields, a high frequency data reconstruction method is proposed. The extrema of the seismic data are used to get the modulation function which operated with the original seismic data to get the high frequency part of the reconstruction data to rebuild the wide band data. This method greatly saves the computation, and easy to adjust the parameters. In the output profile, the original features of the seismic events are kept, the common feint that breaking the events and adding new zeros to produce alias is avoided. And the interbeded details are enhanced compared to the original profiles. The effective band of seismic data is expended and the method is approved by the processing of the field data. Aim to the problem in the exploration and development of Chinese eastern oil field that the high frequency log data and the relative low frequency seismic data can’t be merged, a workflow of log data extrapolation constrained by time-phase model based on local wave decomposition is raised. The seismic instantaneous phase is resolved by local wave decomposition to build time-phase model, the layers beside the well is matched to build the relation of log and seismic data, multiple log info is extrapolated constrained by seismic equiphase map, high precision attributes inverse sections are produced. In the course of resolve the instantaneous phase, a new method of local wave decomposition --Hilbert transform mean mode decomposition(HMMD) is raised to improve the computation speed and noise immunity. The method is applied in the high resolution reservoir prediction in Mao2 survey of Daqing oil field, Multiple attributes profiles of wave impedance, gamma-ray, electrical resistivity, sand membership degree are produced, of which the resolution is high and the horizontal continuous is good. It’s proved to be a effective method for reservoir prediction and estimation.

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Since physical properties and resistivity of mixed formation fluid change after polymer and water flood reservoir, transformational electric properties of water and polymer flooded zones challenges log interpretation. Conventional log interpretation methods to water flooded reservoirs cannot be employed to water and polymer flooded zones. According to difficulties in water and polymer flooded zones interpretation, we analyzed the variation of electric properties of mixed formation fluid, reservoir parameters and log correspondences, then got further understanding of the applicability of Archie Equations. As the results, we provided reservoir parameter evaluation model in water and polymer flooded zones in this paper. This research shows that micro pore structure, physical parameters and electric correspondence of reservoirs change after being flooded by water and polymer. The resistivity variation of mixed formation fluid depends mainly on affixation conductivity of polymer and salinity of formation water, which is the key to log interpretation and evaluation. Therefore, we summerized the laws of log correspondence in different polymer injection ways, developed electric discrimination model for water and polymer flooded zones, as well as charts to identify flooding conditions with resistivity and sonic logs. Further rock-electric tests and conductive mechanism analysis indicate that the resistivity increasing coefficient(I) and water saturation(Sw) are still in concordance with classical Archie Equations, which can be utilized in quantitative evaluation on water and polymer flooded reservoirs. This sets of methods greatly improved accuracy in water and polymer flooded zone evaluation.

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ABSTRACT Base on Dias-model, this paper study the forward modeling to IP response with MT souece and CSAMT source with the author’s program,that is to provide the theoretical basis for extracting the IP information from the far field, near field and transition field in extremely low frequency electromagnetic sounding with artificial strong fixed source signal. The outline of the paper is as follows. Firstly, review the history of the complex-resistivity-model, and analyses the bases for choosing Dias model; meanwhile, effects and responses of each parameter in Dias model are analyses. Afterward, study the forward modeling to 1D layered model with MT source, numerically simulate the IP effects of classic geoelectric objects; Find the clear anomaly and relationship between the peak value of the amplitude anomaly ratio and phase anomaly difference with and without IP parameters to be considered within a frequency range. On the basis of the modeling of MT, Study the CSAMT modeling with a dipole-source, obtain the anomaly responses and the relationship between anomaly and characters of object. Base on the infinite line source, study the 2D IP effect of geoelectric objects with 2D modeling. Calculate the response with different source distance, object depth and different wall rock resistivity systemically. Finally, conclude the viewpoints and give the discussion of the result, and point out the lack of this research also.

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Central Xiemisitai is located on the northwest edge of the Junggar Basin, bounded on the north by Sawuer Mountain, and southward Junggar Basin. Geotectonically, it is within the Chengjisi-Ximisitai-Santanghu island arc of Late Paleozoic, between Siberian and Junggar plates. The volcanics in this area mainly consist of acidic volcanic lava, rock assemblage of esite, dacite, and rhyolite, and the transitional phase is comparatively developed. Besides, Si2O of volcanics here covers a large range of 53.91-79.28t %, K2O of 1.71-6.94t%, and Na2O of 2.29-5.45t%, which is a set of metaluminous- peraluminous high K calc-alkaline to calc alkaline mid-acidic volcanic series. In addition, the volcanics are potassic to high-potassic assemblage, with slight shoshonite in. The REE curve of volcanics in central Xiemisitai is rightward and smooth, inclining to LREE enrichment, which reveals the characteristics of island-arc volcanics. Through the lithology changing from neutral to acidic, the negative anomaly of Eu is increasing. The volcanics here deplete HFSE such as Nb, Ti, P, etc., but relatively rich in LILE like Rb, K, Th, etc., possessing geochemistry characteristics of arc volcanics, which means that the lava source region is watery, under the meta-somatic contamination of subducted components. Moreover, high Ba and Sr show volcanics in epicontinental arc environment, and their contemporaneous granitoid rocks are also marked with the characteristics of volcanic arc granite. In central Xiemisitai, the volcanics zircon age of volcanic rhyolite is 422.5Ma± 1.9Ma, mid-late Silurian. Only one sample zircon has been measured for the present, not very convincing, so volcanics here might not come from Devonian volcanism. Consequently, further confirming the volcanic age will play a key role in the research on the beginning of volcanism in Xiemisitai area and even North Xinjiang. This area includes three copper mineralization types: a) from andesite fracture; b) from rhyolite fracture broken zone, with the copper mineralization distributed by veins along the fissure; and c) from quartz veins. The mineralization of earth surface in S24 ore spot is intensive, and the primary geochemistry reconnaissance anomaly is fairly good. According to display data, the maximum content of Cu is as high as 0.9% and as low as 0.05%. Also, ore-control fracture structure is having a considerable scale in the strike of fracture both horizontally and vertically downwards, and the result of the geophysics stratagem EH-4 system reveals obvious low-resistivity anomaly. As a result, we believe that the S24 plot is expected to be a volcanic copper deposit target area.

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Reservoir characterization and reservoir modeling are two key techniques in petroleum exploration and development. They all are based on the reliable static and dynamic properties of the reservoirs, especially the static and dynamic properties of the reservoirs at each borehole. Without the static and dynamic properties of the reservoir, reservoir characterization and reservoir modeling will pass into nothingness. In fact, the static and dynamic properties of the reservoir are needed in every domain and stage of petroleum exploration & development Today, petroleum industry has reached a stage worldwide that most of the simple & large massive reservoirs have been well explored and developed. As a result, oil companies are paying more and more attention to the exploration & development of the complex & middle to small clastic reservoirs (such as low resistivity sandstone reservoirs, low or no resistivity contrast sandstone reservoirs, conglomerate reservoirs, volcanoclastic reservoirs). In the recent years, oil companies inside and outside China are focusing on the exploration and development elastic reservoirs. Most of the theories & methods being applicable for simple clastic reservoirs can not be used in complex clasic reservoirs. Some theories & methods that are not resolved in the case of simple clasic reservoirs become more impossible to be resolved in the case of complex elastic reservoirs. A set of theories & methods being applicable for computing the static and dynamic properties of the complex elastic reservoirs are developed in this paper and they have been put into practice successfully. These theories & methods are developed by integrating multi-subjects such as geology, well logging and reservoir engineering, in which geology is used as direction and modern well logging technology is used as basis and reservoir engineering is used as assistance and computer technology is used as tool. There are three outstanding breakthroughs in this paper: of the low porosity fractured and/or vuggy carbonate/igneous reservoirs too. A set of practical theories and methods of computing the static properties (such as porosity, saturation, lithology and fluid type) & dynamic properties (such as permeability and production rate) of simple clastic reservoirs have been developed with the hard efforts of many petroleum engineers and scientists in the past 70 years. However, only some of the theories & methods being applicable for simple clastic reservoirs can be used in complex clastic reservoirs after little modification because of the complexity of the complex clastic reservoirs. Most of the theories & methods being applicable for simple clastic reservoirs can not be used in complex clasic reservoirs. Some theories & methods that are not resolved in the case of simple clasic reservoirs become more impossible to be resolved in the case of complex clastic reservoirs. A set of theories & methods being applicable for computing the static and dynamic properties of the complex clastic reservoirs are developed in this paper and they have been put into practice successfully. These theories & methods are developed by integrating multi-subjects such as geology, well logging and reservoir engineering, in which geology is used as direction and modern well logging technology is used as basis and reservoir engineering is used as assistance and computer technology is used as tool. There are three outstanding breakthroughs in this paper:

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The Study on rheology of the lithosphere and the environments of the seismogenic layer is currently the basic project of the international earthquake research. Yunnan is the ideal place for studying this project. Through the multi-disciplinary comprehensive study of petrology, geophysics, seismo-geology, rock mechanics, etc., the depth-strength profiles of the lithosphere have been firstly constructed, and the seismogenic layer and its geophysical and tectonic environments in Yunnan have been systematically expounded in this paper. The related results achieved are of the important significances for further understanding the mechanism of strong earthquake generation, dividing the potential foci and exposing recent geodynamical processes in Yunnan. Through the comprehensive contrast of the metamorphic rocks in early and middle Proterozoic outcropping on the surface, DSS data and experimental data of rock seismic velocity under high temperature and high pressure, the petrological structure of the crust and upper mantle has been studied on Yunnan: the upper, middle and lower crust is composed of the metamorphic rocks of greenschist, amphibolite and granulite facies, respectively or granitoids, diorites and gabbros, respectively, and the upper mantle composed of the peridotites. Through the contrast studies of the heat flow and epicenters of the strong earthquakes, the distribution of the geotemperature and the data of focal depth, the relationship of between seismicity and geothermal structure of the lithosphere in Yunnan has been studied: the strong earthquakes with magnitude M ≥ 6.0 mainly take place at the geothermal gradient zone, and the seismic foci densely distribute between 200~500 ℃ isogeotherms. On the basis of studies of the rock properties and constituents of the crust and upper mantle and geothermal structure of the lithosphere, the structure of the rheological stratification of the lithosphere has been studied, and the corresponding depth-strength profiles have been constructed in Yunnan. The lithosphere in majority region of Yunnan has the structure of the rheological stratification, i.e. the brittle regime in the upper crust or upper part of the upper crust, ductile regime in the middle crust or lower part of the upper crust to middle crust, ductile regime in the lower crust and ductile regime in the subcrustal lithosphere. The rheological stratification has the quite marked lateral variations in the various tectonic units. The distributions of the seismogenic layer have been determined by using the high accurate data of focal depth. Through the contrast of the petrological structure, the structure of seismic velocity, electric structure, geotemperature structure, and rheological structure and the study of the focal mechanism in the seismogenic layer, the geophysical environments of the seismogenic layer in Yunnan have been studied. The seismogenic layer in Yunnan is located at the depths of 3 ~ 20 km; the rocks in the seismogenic layer are composed of the metamorphic rocks of greenschist to amphibolite facies (or granites to diorites); the seismogenic layer and its internal focal regions of strong earthquakes have the structure of medium properties with the relatively high seismic velocity, high density and high resistivity; there exists the intracrustal low seismic velocity and high conductivity layer bellow the seismogenic layer, the geotemperature is generally 100~500 ℃ in the depth range in which the seismogenic layer is located. The horizontal stress field predominates in the seismogenic layer, the seismogenic layer corresponds to the brittle regime of the upper crust or brittle regime of the upper crust to semibrittle regime of the middle crust. The formation of the seismogenic layer, preparedness and occurrence of the strong earthquakes is the result of the comprehensive actions of the source fault, rock constituent, structure of the medium properties, distribution of the geotemperature, rheological structure of the seismogenic layer and its external environments. Through the study of the structure, active nature, slip rate, segmentation of the active faults, and seismogenic faults, the tectonic environments of the seismogenic layer in Yunnan have been studied. The source faults of the seismogenic layer in Yunnan are mainly A-type ones and embody mainly the strike slip faults with high dip angle. the source faults are the right-lateral strike slip ones with NW-NNW trend and left-lateral strike slip ones with NE-NEE trend in Southwestern Yunnan, the right-lateral strike slip ones with NNW trend and left-lateral strike slip ones with NNE trend (partially normal ones) in Northwestern Yunnan, the right-lateral strike slip ones with NWW trend in Central Yunnan and left-lateral strike slip ones with NW-NNW trend in Eastern Yunnan. Taking Lijiang earthquake with Ms = 7.0 for example. The generating environments of the strong earthquake and seismogenic mechanical mechanism have been studied: the source region of the strong earthquake has the media structure with the relatively high seismic velocity and high resistivity, there exists the intracrustal low velocity and high conductivity layer bellow it and the strong earthquakes occur near the transitional zone of the crustal brittle to ductile deformation. These characteristics are the generality of the generating environments of strong earthquakes. However, the specific seismogenic tectonic environments and action of the stress field of the seismic source in the various regions, correspondingly constrains the dislocation and rupture mechanical mechanism of source fault of strong earthquake.

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Since 1970s, igneous reservoirs such as Shang741, Bin674 and Luol51 have been found in Jiyang depression, which are enrichment and heavy-producing. Showing good prospect of exploration and development, igneous reservoirs have been the main part of increasing reserves and production in Shengli oilfield. As fracture igneous reservoir being an extraordinary complex concealed reservoir and showing heavy heterogeneity in spatial distribution, the study of recognition, prediction, formation mechanism and the law of distribution of fracture is essential to develop the reservoir. Guided by multiple discipline theory such as sedimentology, geophysics, mineralogy, petroleum geology, structural geology and reservoir engineering, a set of theories and methods of recognition and prediction of fractured igneous rock reservoir are formed in this paper. Rock data, three-dimensional seismic data, log data, borehole log data, testing data and production data are combined in these methods by the means of computer. Based on the research of igneous rock petrography and reservoir formation mechanism, emphasized on the assessment and forecast of igneous rock reservoir, aimed at establishing a nonhomogeneity quantification model of fractured igneous rock reservoir, the creativity on the fracture recognition, prediction and formation mechanism are achieved. The research result is applied to Jiyang depression, suggestion of exploration and development for fractured igneous rock reservoir is supplied and some great achievement and favourable economic effect are achieved. The main achievements are gained as follows: 1. The main facies models of igneous rock reservoir in JiYang depression are summarized. Based on data and techniques of seism, well log and logging,started from the research of single well rock facies, proceeded by seismic and log facies research, from point to line and line to face, the regional igneous facies models are established. And hypabyssal intrusion allgovite facies model, explosion volcaniclastic rock facies model and overfall basaltic rocks facies model are the main facies models of igneous rock reservoir in JiYang depression. 2. Four nonhomogenous reservoir models of igneous reservoirs are established, which is the base of fracture prediction and recognition. According to characteristics of igneous petrology and spatial types of reservoir, igneous reservoirs of Jiyang depression are divided into four categories: fractured irruptive rock reservoir, fracture-pore thermocontact metamorphic rock and irruptive rock compound reservoir, pore volcanic debris cone reservoir and fracture-pore overfall basaltic rock reservoir. The spatial distribution of each model's reservoir has its features. And reservoirs can be divided into primary ones and secondary ones, whose mechanism of formation and laws of distribution are studied in this paper. 3. Eight geologic factors which dominate igneous reservoirs are presented. The eight geologic factors which dominates igneous reservoirs are igneous facies, epigenetic tectonics deformation, fracture motion, intensity of intrusive effect and adjoining-rock characters, thermo-contact metamorphic rock facies, specific volcano-tectonic position, magmatic cyclicity and epigenetic diagenetic evolution. The interaction of the eight factors forms the four types nonhomogenous reservoir models of igneous reservoirs in Jiyang depression. And igneous facies and fracture motion are the most important and primary factors. 4. Identification patterns of seismic, well log and logging facies of igneous rocks are established. Igneous rocks of Jiyang depression show typical reflecting features on seismic profile. Tabular reflection seismic facies, arc reflection seismic facies and hummocky or mushroom reflection seismic facies are the three main facies. Logging response features of basic basalt and diabase are shown as typical "three low and two high", which means low natural gamma value, low interval transit-time, low neutron porosity, high resistivity and high density. Volcaniclastic rocks show "two high and three low"-high neutron porosity, high interval transit-time, low density, low-resistance and low natural gamma value. Thermo-contact metamorphic rocks surrounding to diabase show "four high and two low" on log data, which is high natural gamma value, high self-potential anomaly, high neutron porosity, high interval transit-time and low density and low-resistance. Based on seismic, well log and logging data, spatial shape of Shang 741 igneous rock is described. 5. The methods of fracture prediction and recognition for fractured igneous reservoir are summarized. Adopting FMI image log and nuclear magnetic resonance log to quantitative analysis of fractured igneous reservoir and according to formation mechanism and shape of fracture, various fractures are recognized, such as high-angle fracture, low-angle fracture, vertical fracture, reticulated fracture, induced fracture, infilling fracture and corrosion vug. Shang 741 intrusive rock reservoir can be divided into pore-vug compound type, pore fracture type, micro-pore and micro-fracture type. Physical properties parameters of the reservoir are computed and single-well fracture model and reservoir parameters model are established. 6. Various comprehensive methods of fracture prediction and recognition for fractured igneous reservoir are put forward. Adopting three-element (igneous facies, fracture motion and rock bending) geologic comprehensive reservoir evaluation technique and deep-shallow unconventional laterolog constrained inversion technique, lateral prediction of fractured reservoir such as Shang 741 is taken and nonhomogeneity quantification models of reservoirs are established.

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This paper builds the model of oil accumulation and achieves the prediction of exploration goal. It uses multiple subject means, the ways of synthetic research and the viewpoint of analyzing genesis, with the academic guidance of sedimentology, structural geology, petroleum geology and geochemistry, the basis of strata sequence frame and structural frame, the frame of "four history" - the burying history, the structural history, the filling history and the evolving history of oil, the masterstroke of hydrocarbon's generation, migration and accumulation, the aim of revealing the genetic relation between mature source rock and oil reservoir in space and time. Some achievements and viewpoints in this study are following. 1. It is proposed that the structural evolution in this area had many periods, and the structural movement of the Xiazijie group telophase formed the structural pattern for the first time. 2. The character of strata sequence in this area is divided by the character of episodic cycle firstly. The study of dividing the facies of single well and the facies of well tie is based on the data of single well. The character of sedimentary facies is con-structed initially. 3. It is believed that Jiamuhe group is the main source rock, which can supply considerable oil and gas resources for the first time. Some criterions of source rock such as the type ,the abundance in Jiamuhe group are analysed. Using the thermal history of source rock, we drawn a conclusion that the original type of source rock in Jiamuhe group is II_1-III, and the abundance achived the level of good source rock, and this set of source rock had contributed to this area. 4. The reservoir strata in this area are assessed and analysed with the reservoir evaluation. There are multi-type reservoirs, such as volcanic lava facies, sedimentary clast facies, continental belch facies. The physical property in reservoir strata is characterized by low porosity and low permeability. The study of diagenetic stage show that the diageneses in Jiamuhe group is A-Bsubage, and the reservoir room is mainly secondary corroded hollow and cleft. 5. The synthetic research on oil system in Jiamuhe group is made for the first time. The type of petroleum system is divided , and we consider that the petroleum system of Jiamuhe group is at the reliable rank. There are two critical time in oil accumulation through studying the critical time of oil accumulation : the early generation of hydrocarbon is oil, and the later is gas. 6. The mechanism of accumulation is analysed. We consider that the accu-mulation of oil in this area has many periods, and the early generated hydrocarbon is expeled by the later , and formed the character of zonal distribution in planar. 7. A bran-new model of oil and gas is proposed. Beneficial enrichment area of oil and gas is analyzed, which can be divided into three sections: Section I can be divided into two sections: I_1 and I_2. The lower subgroup of Jiamuhe is covered by the triassic layer of I_1 section. Fault zone and near the foot wall of fault are charactered with thick phase belt. Then the cover capability in this area is relatively poor, oil can migrate into triassic layer by vertical or lateral migration , and forms I_1 Kelamayi triassic oil pool consequently. The lower subgroup of Jiamuhe is covered by the triassic layer of I_2 section ,which is charactered with thin phase belt. Then the cover capability in this area is relatively good, and forms I_1 Kelamayi triassic oil pool consequently. Section II can be divided into two sections: II_1-I_(I~2). The cover of Jiamuhe group in section II_1 is the low resistivity segment in Wuerhe group, which has thin lithology and poor porosity and permeability. Oil and gas in Jiamuhe group can be covered to form beneficial accumulation area. There are some wells in this area, such as Ke 007 well, 561 well. The thick phase belt layer of Wuerhe high resistivity segment in section II_2 has unconformable relation with Jiamuhe group. The cover ability of the high resistivity segment is poor, petroleum in Jiamuhe can migrate into Wuerhe layer vertically. This area is the beneficial area for accumulating petroleum in Wuerhe layer. there are some wells in this area, such as Ke 75 well, Ke 76 well, Ke 77 well, Ke 78 well, Ke 79 well. Section III can also be divided into two sections: III_1 and III_2. Wuerhe group in section III_1 has unconformable relation with Jiamuhe group. There is thick lithology and poor cover in Wuerhe group, but the strata sequence evolution character of upper subgroup in Jiamuhe group has determined that it has lateral and vertical cover ability. thus, this area is petroleum abundant belt of jiamuhe group, which has the trap. Section III_2 is an area controled by wedgeout of Fengcheng group, Fengcheng group in this area has quite thick lithology so that It has beneficial resevoir phase belt. It can accumulate oil in itself or accept some oil in Jiamuhe group. Jiamuhe group has some oil accumulation condition in this area. Thus, section III_2 is jiamuhe-Fengcheng multiple petroleum accumulation belt, such as Ke 80 well. 8. The goal of exploration is suggested: Depositional trap or combination trap is the important aspect in later exploration. Both types of traps are the goal of the next drilling: Fault block trap in the east of 576 well and the NO. 2 fault block trap in the north of Ke 102 well It is suggested that we should study the law of oil and gas in Jiamuhe group and enhance the study of combination in forming reservoir and trap scale. We do some lithology forecast and reservoir diatropic forecast in order to know the area of oil and gas.