| Seismic reservoir prediction is based on high-resolution seismic and log data, geological and drilling data as a reference, the wave impedance inversion and attribute analysis techniques as the main technology, therefore, the effect of wave impedance inversion and the use of attribute parameters become a key of reservoir prediction.Danan Sag area is a continental fault basin, in which, structure is complex, fault is developed. It has the advantage of developing formation lithologic trap. But it is short of effective evaluation technology to confirm and evaluate formation lithologic trap, of which the most prominent problem is that the structural details is not clear, favorable sedimentary facies belt and the effective range of available reservoir is not clear, and regular pattern of oil and gas accumulation of formation lithologic trap is uncertain.Through this analysis and research,it can be concluded that oil and gas shows the best results in E2S2 of Danan sag, followed by E2s1, and the worst in E2S3. Oil and gas of E2s is mainly distributed in northern part of the study area, and central and southern drilling is less, particularly in the south is almost empty. Luxiang fault has the better condition of hydrocarbon source rocks, big thickness of dark mudstone, medium abundance of organic moderate, and it is in the mature stage. E2s3 has the biggest dark mudstone, followed by E2s1; the organic richness and organic maturity of E2s1 and E2S2 are slightly higher than E2S3. Comprehensive evaluation shows that the E2s1 is the most favorable, followed by E2s3; Luxiang Basin Danan sag is the most favorable areas, followed by the north-central and southwestern parts of the basin, the eastern part is the relatively poor oil generation zone, the main causes of formation reservoirs type are fan delta and subaqueous fan sand bodies, and structure mainly are the main block traps in Luxiang Basin.This study makes full use of the existing various kinds of information, takes geological, logging, reservoir engineering multidisciplinary as theory instruction, has a comprehensive application of drilling, seismic, logging, laboratory analysis and production performance data, makes Danan sag as the main study area, focusing on bedrock hill, the E2s1 conglomerate, E2s2 sandstone and E2shi fan to start work, and forms a more complete research methods, guides the district analysis better. The research method can also be used as a reference for similar studies.Based on these studies above, we acquire the following outcomes and understandings.1. According to the Danan sag data analysis, combined with previous geological aspects and interpretation results of this area, integrated sequence interface, internal structure and characteristics of sedimentary evolution, E3w to E2S can be attributed to the group E2S, E2sh, E2y, E3w. four secondary sequence,10 three-grade sequence.2. From stratigraphic correlation analysis, E2S is distributed within the whole region, thickness change is bigger, exposed thickness is 500-600m by drilling, lithology is black-gray mudstone, siltstone and fine sandstone-conglomerate, and conglomerate is at the bottom. It is Longitudinally divided into three lithology section, with unconformity contact to the underlying.3. According to the interpretation results of the seismic velocity spectrum analysis, a 3D average velocity field is established. By the comparison analysis of extracted time-depth curve of the earthquake velocity and calculated time-depth curve of sonic logging, it shows that the speed has the same trend and the error is smaller. It provides reliable 3D velocity field data for structural interpretation and reservoir prediction.4. Danan sag is controlled and by the northwest the southeast margin squeeze fault, the later tectonic transformation is relatively large; traps in the study area is basically divided into three categories:structural traps, stratigraphic traps and lithologic traps.5. E2S sandstone reservoirs are well developed in this area, which is mostly distributed in the northwest and southeast faults, sandstone thickness obtained from the inversion analysis diagram shows E2s2 sand thickness is nearly up to 400m, in the X27 block and southern sand thickness is bigger, in the vicinity of the 2nd fault is relatively thin, compared with statistical calculation results and actual drilling of sandstone thickness, self-agreement is above 80%; Development of E2s1 is uniform, the maximum thickness of the sand body of nearly 200m, the thickness is near the L2 wellblock appeared, other parts of the sandstone thickness is between 50-100m.6. Work area reservoir is mainly in E2s and E2sh, which is characterized by many thin oil reservoir and structural lithology; source bed mainly is in the upper part of E2s1 mudstone and large set of E2s3 shale, reservoir is mainly in E2s1 basal conglomerate E2s2 sandstone, sedimentary center moves from south to the north, forming the present pattern.7. Appropriate research methods will be an important means of finding such a small depression beneficial goals. The research on the Danan sag seismic and geological data features guided by the theory of sequence stratigraphy, sedimentary rift basin model, On the basis of isochronous stratigraphic framework of Danan sag, structure, reservoir and hydrocarbon accumulation and distribution rule of oil and gas is studied, finding suitable inversion method in the region and sensitive attributes at the same time and establishing the favorable zones. |
PDF Full Text Request