Geological Characteristics And Development Index Prediction Of Sub-layer Reservoir Of B Group In A Block Of Daqing Placanticline

A block is located in the east of SA oilfield in Daqing placanticline.It was put into development in 1960.It has been adjusted by one or two times and three times,and a group of main oil reservoirs,polymer flooding wells,have been put into use.In June 2013,the new wells were put into production in succession,and the water flooding was started.By the end of 2014,the recovery rate was 49.61%.This paper selects the A block as the research object,take the B group as the research focus,based on a full understanding of the geological characteristics of A block,reservoir characteristics,fluid properties,geological reserves and mining degree;furthermore,the fine reservoir description,understand the situation and the distribution of remaining oil reservoir development;the comprehensive development index forecast the method of numerical simulation method,N ii Tong's chart method,well logging data,the effective evaluation and verification of the stage of development.The analysis shows that the B group of two oil geological reserves of A is 1399.64×104t;fine reservoir description,analysis of sedimentary characteristics of 18 sedimentary units,mainly divided into 2 sedimentary facies,4 sedimentary types,summarizes the features one by one;analysis of remaining oil by using logging data,Nii production data,through numerical simulation study of residual oil distribution to.The above shows that,after more than 50 years of waterflood development,A block two class reservoir all over,see water,high water thickness ratio of 90%,the remaining oil distribution is scattered,mainly in the plane of injection production relationship is not perfect,well unused;vertical concentrated at the top of thick oil layer.By phase control modeling,the final recovery rate of two types of reservoir water flooding in A block is 45.3%.After ASP flooding,the recovery rate can be increased by 16.4%,the cumulative increase of oil is 229.54×104t,and the ultimate oil recovery of reservoir is 61.7%.By the year of April 2016,the extraction rate of polymer flooding stage was 3.66%,and the average single well oil production was 1257 t,and the water cut decreased by 7.2 percentage points,which provided a theoretical basis for the later development of A block.