Study On Reservoir Distribution And Heterogeneity Characteristics Of Slmiddle Reservoir In Jin Sixteen Block

Reservoir is the main object of study in the oil and gas exploration and development, which is the core of oil and gas reservoirs, and which is the ultimate goal of the comprehensive study in petroleum geology. The resource, production, deloverabi--lity of oil and gas can be closely related with reservoir properties. The important task of studying reservoiris is to in depth study macro-distribution, internal structural, reservoir parameters distribution, pore structure characteristics of the reservoir and the dynamic characteristics of the reservoir layer in the oil and gas development, services in oil and gas exploration and development.The paper’s study is the middle reservoir of Shahejie one group in Jin Sixteen block,which is located in the western depression of Liaohe rift basin. It’s formation to the small continental rift basin in Mesozoic and Cenozoic, especially since the Paleogene,which is located in the northeast corner of Bohai Bay Basin, China. On the basis of previous research, using of logging, drilling,3D seismic and reservoir static and dynamic data,and integrated application geological work and reservoir description. Analysis in the fine stratigraphic comparison, tectonic, sedimentary, reservoir, the system description of the area’s sedimentary microfacies,reservoir characteristics,and then comprehensive evaluation of the reservoir, made a concluding controlling factors of high-quality reservoir development.Yulou reservoir of first paragraph Tertiary Shahejie group is the intended zone of Jin Sixteen block,Huanxiling oilfield, which structure located in the southern section of the western slope,the western depression,Liaohe rift basin.And formed broken nose construct is developed on slopes. Shahejie Formation is divided into four sections in the region of interest,namely one,two,three and four paragraphs. Object of study is the middle of first paragraph in Shahejie group.Though studying sedimentary facies in Jin sixteen block,and analysis shows that the main depositional system in the sandstone group of Yulou reservoir is the fan delta.And Yulou reservoir is located in the middle of first paragraph in Shahejie group. Lower Liaohe Depression construct a steady decline to the rising transition during the deposition period of the middle of first paragraph in Shahejie group. The fault lacustrine basin is to atrophy from expansion,depositional mode is from retrogradational into progradational.On the whole,Yulou reservoir is formed in the fan delta continued into progradational of fault lacustrine basin. From the bottom to up, the overall is to coarsening from fine reverse grading. Facies-controlling of reservoir is obvious, mainly developed fan delta front facies, underwater distributary channel is the most favorable sedimentary facies.Through studying the reservoir,and acquire the following findings:One. According to the reservoir static and dynamic data to determine criteria for the classification of Yulou reservoir in Jin sixteen block,in order to complete the small unit lever for the fine delineation of stratigrphic correlation and sedimentology of modern theory as a guide,comprehensive using core,logging and other information,the use of "cyclic control, classification comparison" principle,to determine the2sets of oil group,6sets of sand group,11small layer hierarchical model.Two. The establishment of a depositional model of Jin sixteen block reservoir to the small unit level for the sedimentary microfacies,descrybes the characterics of different micro-phase,and an analysis of sedimentary microfacies and the relationship between development and production;use of core data,well logs on sedimentary facies of a reservoir system,the fan-delta source areas from northwest direction,southeast advance.Jin sixteen block reservoir is the fan-delta system,fan-delta front subfacies in the deposition as the main body including underwater distributary channel, the shunt between the Bay and the mouth bar microfacies,outside the fan-delta is clay microfacies deep lake,which is not development.On the basis of studying sedimentary microfacies, and analysis the macro-distribution characteristics of the target sand body, clarify the characteristics of geometry, spatial and temporal distribution in reservoir sand bodies, and comprehensive evaluation of reservoir.Tree. The characteristics of reservoir petrology:the Yulou reservoir rock types are mainly lithic arkose and feldspathic lithic sandstone, second, there are feldspathic sandstone, mixed sandstone and bioclastic sandstone. Detrital content of the rock composition is generally98%to99%, minimum70%,average89%, quartz and feldspar are mainly in the detrital, quartz content of7%to58%, average35%; feldspar4%to39%,average27%; followed by igneous rock debris, which content of36%, average14.1%.Sandstone grains is medium, grain size is concentration, gradation poor to medium; particle roundness subedges to subrounded, the components of the interstitial material is generally5%to6%,up to30%,average4.56%, argillaceous cement is mainly,so cement loose. Above the analysis shows that the rock structure maturity is low in the area,which is the past material sources, short-distance transportation. Pore types are mainly native intergranular pore, followed by dissolution pores, intergranular holes,cracks, and other secondary porosity, particle cement type is pore to pore contact. On the basis of the above analysis, combination the porosity and permeability data collected in Jin sixteen block to study the characteristics of reservoir,findings show that Yulou reservoir is the typical high,middle porosity and high permeability. Porosity range between0.03%to41.39%, average15%to35%; penetration range between0.01to6316.9×10-3um2,average729.17to2801.2×10-3um2of Yulou reservoir in the middle of first paragraph in Shahejie group. Pore throat connectivity is better, the type of pore structure was mainly hypertonic, big hole and middle throat,and distributed in the underwater distributary channel microfacies.Study the heterogeneity of the reservoir, can reveal the distribution of changes in the three-dimensional space,which have an important guiding significance in correcting understanding and the transformation of the reservoir, deploying a reasonable well network, developing a reasonable development programs, as well as to determine a reasonable stimulation to improve the development effects. Heterogeneity characteristics of the reservoir show that:aeolotropism is medium in a small layer and each sand groups of Yulou reservoir in Jin sixteen block, belonged to the middle heterogeneity. Plane, the different layers and facies heterogeneity have certain differences, which have a great impact in the wells arrangement, the plane sweep and efficiency of injected water and the horizontal distribution of the residual oil.Four. Multi-factors govern the physical properties of the clastic reservoirs. The degree of development, physical features and its temporal and spatial distribution of the reservoir is controlled by deposition, diagenesis, tectonic activity and other elements. Rock types and sedimentary microfacies equal to control the type, scale, porosity and permeability characteristics and spatial distribution morphology of reservoir sand bodies in the macro, and resistance to the ability of the post-transformation; diagenesis and tectonic activity transformate the original conditions, which effect reservoirs porosity evolution and properties changes in the micro, the reservoir properties significantly reduced after strong compaction, pressure solution cementation and other diagenesis transformation, but the reservoir space changed for better while the dissolution of feldspar grains in the burial; construct fracture development in activities conducive to improve the reservoir properties, plays an important role in promoting the formation of favorable reservoir.Understanding and awareness of the results of previous studies, familiar with the study area’s geological setting and the sedimentary evolution of the stage in target layer, which is the first paragraph of Shahejie group in Tertiary, through applying a small layer contrast, establishment deposition phase diagrams, the reservoir properties and heterogeneity plan diagrams in a small layer units to predict reservoir macro-distribution. Based on the above results, studying the deposition system’s distribution characteristics of the stratification in different periods, to identify the horizontal distribution and physical characteris--ics of the sand body type in different layers, and combined with the findings of the fine structure, to provide a good research ideas in the similar oil and gas reservoir exploration and development.