Reservoir Description Of Putaohua-Fuyu Oil Layer In Z25 Block Of Daqing Oil F1eld And Optimization Of Favorable Area

Z25 block tectonic position is located in two secondary tectonic belt transition zone of Sanzhao sag in the central depression area of the Songliao basin and Chaoyang ditch terrace.Zhaozhou nasal structure belongs to a three grade structure of the southern periphery of the Sanzhao depression in Toutai-Zhaoyuan-Zhaozhou nasal tectonic group.Since its production in 2005,two Oil-bearing blocks Z25 and O27 have been developed.At present,there are three main problems in the Z25 block: first,the developed blocks are low permeability,low productivity and low abundance reservoirs with insufficient development potential.;Second,the cause and type of remaining oil in block are not clear;third,the vertical and horizontal distribution law of remaining oil is not clear.So it is urgent to put forward reasonable adjustment countermeasures to guide development and improve the effective and economical utilization of surplus reserves.The paper predicts the main reservoir distribution of Fuyang-Putaohua in the extended area of block Z25.Through the analysis of the oil and gas distribution and the control factors of the existing reservoir,the reservoir model which conforms to the geological characteristics of this area is set up,and the distribution law of oil and gas is summed up so as to know exactly the drilling potential of oil and gas in the extended area,and point out the favorable oil and gas enrichment zones(blocks)to make the next drilling evaluation deployment.In this paper,five parts of the research are carried out.The first is to have an overview of the deposition scale of sand body in the target layer and development of oil bearing sand bodies.The second is to clarify the structural characteristics,fault properties and reservoir distribution prediction of seismic layer.The thirde is to study the distribution characteristics of oil and water,define the main controlling factors of accumulation,and establish the reservoir forming mode.The fourth is to carry out the classification evaluation of the oil layer.The fifth is about the favorable Area Optimization and evaluation.The research results of this paper can comprehensively and deeply understand the prospect of oil and gas in the extended area of Z25 block,and put forward suggestions for further development and evaluation deployment.That is,it is suggested that the PI oil layer in O31 well area is fractured before production;Z25 ~ Z97-17 well area and Z75-27 well area are the next favorable direction of evaluation and deployment in peripheral area,The Z75-27 well areas are the primary evaluation targets for its relative development of reservoir and abundant drilling;The Z95-25 ~ Z102-26 well areas is the favorable direction for rolling development of O251 development block.The research results have important guiding significance for the future development of Z25 block.