The3D Geological Model And Lithologic Stratigraphic Reservoir Prediction Of Kongdian Formation, Kongnan Area In Huanghua Depression

Kongnan area was located in Cangdong and Nanpi Sag of the southern of Huang-hua Depression, The east and west sides is Cangdong fault and Xuxi fault; The northside is NanDi; The south side is DengMingsi. It was the favorable oil and gas zone ofHuanghua Depression. The buried hill and structural reservoir of the study area has hi-gh degree of exploration, but the lithologic and stratigraphic oil and gas has less degr-ee of exploration. On the basis of previous research, We has recognized the structuralfeatures of basin of the study area in Kongdian formation was different from the struct-ural features of the current residual basin, the basin suffered multiple stacking. Postte-ctonic movement was strong structural transformation of the early basin. At the sametime the the Kongdian basin structure type, source and depositional system, palaeogeo-graphy and basin evolution of the process, recognize the existence of a big problem.These problems have seriously restricted the reunderstanding of distribution of oil andgas resources of Kongnan area, and serious impact on the progress of explora-tion ofthe lithologic and stratigraphic reservoir.This study is to proceed from the basic geology of the study area, structural featu-res, and sequence stratigraphy, sedimentology, geophysics and other disciplines as aguide, Comprehensive analysis of the drilling cores, logs and logging data, seismic da-ta and other information on Kongnan area in Huanghua Depression, we studied the c-haracteristics of sequence stratigraphy and sedimentary system of Kongdian formati-on eriod of Kongnan area in Huanghua Depression. On this basis by three-dimension-al geological modeling techniques, we established three-dimensional geological struc-ture model of the research area, analyzed the residual basin structure type of Kongdia-n formation of the reserch area, and sedimentary response process, formation processof Kongnan tectonic uplift zone; And on the basis of three-dimensional structural mod-el, by faces deterministic modeling techniques, we established each sequence of three-dimensional deposition model of the research area, and by recoverying constructe an-d analyzing sedimentary facies, we restored paleogeographic framework and evoluti -on of each sequence in the research area. By well log constrained seismic inversionmethods and spectral analysis techniques, we was predictive analysis of the sand bodyand detection containing the oil and gas of reservoir of the research area, to identify fa-vorable development site of sand body, combined with a favorable combination of re-servoir, predicting each sequence of favorable stratigraphic reservoir, these were imp-ortant guiding role in oil and gas exploration. We have made an impotant understand-ing of the following points:(1) Utilizing sequence stratigraphy of continental basins third of the classificati-on principles, we divided Kongyi formation and Konger formation of Kongnan areaof Huanghua Depression into3third-order sequences and8fourth-order sequences,9system tracts,9medium-term base-level cycles and16half cycle. The sequence I is e-quivalent to Konger formation and the bottom of ZaoⅤ oil group. The sequence Ⅱisequivalent to the upper part of ZaoⅤ oil group of Kongyi formation and the bottom ofZaoⅣ oil group. The sequence Ⅲ is equivalent to the upper part of ZaoⅣ oil group a-nd Zao0oil group. We identified three types of filling pattern of medium-term base-l-evel cycles, and established the sequence stratigraphic model of Kongdian formation.(2) On the basis of sedimentary facies, seismic facies, lithofacies sedimentary offacies identification mark, we analyzed sedimentary facies and depositional systems o-n Kongdian formation of Kongnan area. We identified the sequence Ⅰ that it was co-mbination of slump turbidite delta-deep lake, semi-deep lake sedimentary facies, ident-ified the sequence Ⅱ that it was combination of alluvial fan-braided river–floodp-lain sedimentary facies, and identified the sequence Ⅲ that it was alluvial fan-braid-ed river-floodplain-cream Salt Lake sedimentary facies.(3) By three-dimensional geological modeling techniques, utilizing modeling me-thod based on surface, we established3D geological model of Kongnan area of Kong-dian formation, and analyzed and obtained of two basin structure type of residual bas-in of Kongdian formation. On the basis, we analyzed Cangdong fault and Xuxi faultcontrol of the deposition at time and space, the studies suggested that the activity of C-angdong fault was weak at the Sequence Ⅰperiod, and only the eastern section of Ca-ngdong fault was activity, the whole of Cangdong fault started activities at the Seque-nce Ⅱ and Sequence Ⅲ period, and the strength continued to improve, which reache-d the maximum at the Sequence Ⅲ period, becomed the controlling faults of the basi-n. The activity of Xuxi fault was weak or inactive at the sequence Ⅰ period, not yetobvious control on the west side of the plate sediment deposition, Xuyang section of Xuxi fault began to the role of the tensile at the sequence II period, the whole of Xuxifault had a strong the role of the tension at the sequence Ⅲ period, which controled onits west side of the plate sediment deposition, becomed the controlling faults of the ba-sin.(4) In fact, Kongdian uplift belt was a derived product of activity of Cangdong fa-ult and Xuxi fault, which was the result of a bend fold role formation. Kongdian upli-ft belt began to develop during the deposition of sequence II, and continued to upliftduring the deposition of sequence III, to form a bulge.(5) On the basis of three-dimensional structural model, utilizing the deterministicmodeling techniques, we established3D sedimentary facies model for the study area o-f each sequence, by constructing a recovery and the sedimentary facies analysis, andrestored paleogeographic framework and evolution of each sequence in the research ar-ea. The study thought that the evolution of lake basin of Kongdian formation at the K-ongdian period experienced a depression-fault sag-faulted three tectonic stages, co-rrespond, respectively with the developmental stages of three sequence stratigraphy.(6) There were more drilling and quality of seismic was better at the Kongnan ar-ea, we carried out model-based logging constrained inversion. Through the inversionresults of analysis, it revealed the spatial distribution characteristics of the lithology ofthe research area. On this basis, we combined with drilling data, and conducted charac-terization, drawing the maps of each sequence of the sand body. We analyzed the lawof the sand body of each sequence, and pointed out that the favorable position of the d-evelopment of the sand body.(7) Spectrum decomposition technique not only predicted the thickness of the sa-nd body, but also had better prediction of hydrocarbon potential. The results of the sp-ectral decomposition showed better of Oil and gas of ZaoⅡ, and ZaoⅢ, and ZaoⅤ o-f Kongyi formation, and Konger formation, that conformed to the actual drilling resu-lts.The result showed that time-frequency continuous wavelet transform (TFCWT) sp-ectral decomposition was an effective method in the research area.(8) According to sequence characteristics and sedimentary configuration, we tho-ught that the development of the mainly stratigraphic traps in the research area inclu-ded updip pinchout, unconformities, the delta front and slump turbidite and other mai-n types. Combined with the favorable combination of reservoir, we predicted the distr-ibution law of stratigraphic reservoir.The main innovation of this article: (1) Using three-dimensional modeling techniques, with modeling method based o-n surface, we bulided three-dimensional geological structure model of Kongnan area,analyzed the relationship between tectonic and sedimentary response, migration patter-ns and patterns of settlement center, and restored the basin palaeogeography. We divi-ded into three evolutionary process, that was the depression period, fault-depressiontransform period, faulting period.(2) Using well seismic base-level cycles matching analysis method, and compre-hensive utilization of drilling data and seismic data, we explicited specific seismic re-flection axes significance in sequence stratigraphy.(3) Using the Seismic inversion technology and spectrum decomposition techniq-ue, we predicted the reservoir. We conducted petroleum detection of basin, The resul-ts of spectral decomposition conformed to the actual drilling results. Based on seism-ic sedimentology along the layer slice, with sub-frequency stratigraphic slices emula-ted, we achieved the purpose of the prediction of hydrocarbon potential of reservoir.