| Liuzhuang area is located in the central part of the central uplift, Dongpu depression. It is typically characterized by a broken fault-block zone in which the faults are densely developed with chaotic, irregular distribution features. The reservoirs in this area consist of a lot of different types of sand body, with thin individual intervals and poor lateral continuity so that the reservoir is difficult to evaluate. Thus, improving the accuracy of reservoir prediction and overcoming the multiple solutions of the seismic interpretation is vital important to the exploration and production in this area.This paper presents an integrated approach of reservoir interpretation according to the research of the characteristics in terms of geological setting and seismic reflection of Liuzhuang area. Detailed sequence stratigraphy analysis, sedimentology interpretation and reservoir geology researches are conducted by using core analysis data, log data, and seismic data, combined with the application of geophysical techniques, an integrated reservoir interpretation method is developed. The practice of this method is given by following steps: using high-resolution sequence stratigraphy geological analysis, associated with coherence technique, a highly precise constraint model of the strata is generated, which improves the reservoir prediction accuracy. Considering the provenance of sedimentary and sedimentary facies into log data normalization process, the availability of log constraint inversion is much enhanced. Using the results of sedimentary facies analysis as constraint factors in the inversion, the results between the inversion and the sedimentary facies are crossly verified in order to restrict the randomicity and enhance its rationality of the inversion. The effectiveness of the prediction results are also improved.Updated geological understanding of this area is obtained from the multidisciplinary study, which can be summarized as:1. The structure in this area is characterized by multi-phase faults development and stack. Most of the major faults are formed during the late period of Sha-3 member deposition, and tectonic activity is relatively stable during the Sha-2 member deposition. Influenced by the lower strata uplifting during the later Dongying formation deposition, the tectonic activity seems relatively strong, and two groups of normal faults dipped down closely from each other in NE-SW strike are formed, which resulted in a further cutting and reconstructing to the original structure. Thus, a complex feature in this areaoccurred in terms of"uplift occurring in depression and depression occurring in uplift".2. Sha-1 and Sha-2 member are identified as a third-order sequence, but Sha-3 belongs to another third-order sequence. The lower sub-member of Sha-2 can be subdivided into 7-8 middle-term base-level cycles and, the upper sub-member of Sha-2 can be subdivided into 1-3 middle-term base-level cycles. The Sha-1 can be roughly subdivided into 3-6 middle-term base-level cycles.3. Due to the direction of water inflow changing dramatically during the lower sub-member of Sha-2 deposition, the original sources of this area are obviously direction oriented, and it mainly comes from the south, east and north of the basin respectively, with the south as the dominated direction. The sedimentary environments in this area are characterized basically by coastal shallow lake and overflow shoal changing frequently. Six types of sedimentary microfacies can be identified in this area, they are flood channel deposit, channel edge overbank deposit, interchannel overflow deposit, muddy shallow flat, sandy shoal and shoal sandy bar.4. The sandstones reservoirs of lower the sub-member of Sha-2 comprised mainly of flood channel sands, beach sands from sandy shoal reworked by waving, and channel edge overbank sands. Vertically, it shows the characteristics of much sand with thin thickness. The intervals deposited during the III, IV and V base-level cycles have a high level of sandstone contents with good petrophysical properties. Horizontal sandstone distribution exhibits an obvious direction but in a poor lateral continuity. The sand body is mainly developed in a north-south trend, mostly concentrated in the Well Liu-16-15 block on the southern part, and Well Liu 20-37 block on the northern part of the Liuzhuang area..5. The sandstone is in the stage A-B of late diagenesis. The main reservoir in the area consists of the light gray siltstone and fine sandstone, the range of porosity is from 5% to 20%, mainly at 8%. Permeability ranges from 0.2 to 10 milldarcy. The reservoir sandstone is categorized as medium porosity with low permeability or low porosity with low permeability. Two main factors that affect the quality of the reservoirs are sedimentary microfacies and carbonate cementation during the late diagenesis stage.6. Natural gamma-ray log has the best correlation between the lithology and electric property; it is then followed by acoustic, spontaneous potential, apparent resistivity, and deep induction resistivity logs. The content of marl in the upper sub-member of Sha-3 and the lower sub-member of sha-2 have less influence on distinguishing sand from mudin logging data, in contrast, it exhibits a greater impact on reservoir prediction in the Sha-1 member.7. Natural gamma ray inversion result exhibits a relatively higher correlation with well rather than acoustic impedance inversion. The upper sub-member of Sha-3 exhibits a better continuity with lower formation dipping angle in the western slope area, and the inversion result of this sub-member has a higher reliability. In contrast, the lower sub-member of Sha-2 in the broken fault block area is characterized by great strata dip changing and disordered phase axis of seismic reflection, thus the inversion result exhibits poor continuity which in turn was largely influenced by the initial model8. Based on integration to the structural interpretation, sedimentary facies analysis, reservoir inversion, petrophysics analysis and oil and gas bearing analysis, the good targets for progressive exploration and development of the lower sub-member of Sha-2 are considered to be in the south local structure of Well Liu-2 and to the northern area of Well Liu-16, with target intervals being ofâ…¡-â…£sand group within the lower sub-member of Sha-2. Meanwhile, the target area of the upper sub-member of Sha-3 is located in the northern area of Well Liu-28, with target interval corresponding to the interval with the depth ranging from 4400 to 4600m in Well Liu-28.
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