Study On The Sedimentary Facies Of Member 4 Of Quantou Group In Daan J South Block

Da'an Oilfield located in the secondary structural belt of the Da'an-Honggang terrace in the central depression of the Songliao Basin. J south block is located in the south of Da'an Oilfield, near the anticline structure shaft, belonging to the tectonic-lithologic reservoir.There are main faults and one secondary fault are developed in the block,whose faults are northwest westward. Due to the impact of small fault cutting, it leads to small fault and the west of the main fault zone area of the well pattern irregular.The study of predecessors is mainly for the whole Da'an oil field,rarely on J south block for fine study, but by the lithology, structure and other effects, the sedimentary microfacies between the blocks are very different. And because the deposition system of special, predecessors of this controversy. Therefore, it is very siginificant to fine-graize the stratigraphy and fine-grained facies study, which is very important for the next reservoir evaluation, oil and gas accumulation research and exploration and development.Based on the logging data as the main data and the conventional identification of the logging curve,integrated applying for the maximum entropy spectrum analysis, we can establish the sequence of J south block in Da'an Oilfield stratigraphic division scheme. The four sections of the study area are divided into 14 geological layers of four oil groups.Finally, the high-resolution sequence stratigraphic framework of the study area is established.By plotting the mudstone color index floor plan?ZTR index floor plan? sand thickness and sand ratio plan map of Daan Oilfield and J south block, combined with the single well facies analysis, core photos and regional sedimentary facies of Songliao Southern Basin, it is concluded that the four sections of the study area are from the western Baicheng water system and the southwest Baokang water system.Mudstone color is mainly brown or purple, some areas are gray-green,gray. The latter is mainly distributed in the upper part of the fourth part of the spring, reflecting a process of water into the deposition ,indicating that the four sections of the surface sediments are mainly in the land oxidation environment. The main types of sandstone are feldsphere lithic sandstone, and feldspar and cuttings are high, and the content of stable components is low; Detritus particles roundness is poor, and sorting is good, and shows point-like contact, high matrix content, low structure maturity, indicating that the material source closer or by the transformation of the smaller. According to the above phase sign, the comprehensive analysis of the study area is the fourth stage of the development of the end fan deposition system. The characteristics of the end fan different from those of the other sedimentary facies,it shows :The sandbody is rich in mudstones, and the parallel bedding is directly developed on the scouring surface of the river. Based on the analysis of the sandbody and the microfacies, the thickness plane of the sand bodies in J south block of member 4 of Quantou group of in the south of Jannan Oilfield in Da'an Oilfield is plotted, and the microfacies of the sedimentary microfacies are plotted. Finally,The distribution pattern of the sand body and the law of spatial and temporal evolution are clarified.