Adjustment Of Development Plan Of Putaohua Oil Layer In Zhao25-58Well Area Of Songliao Basin

Zhao25-58well area belongs to zhaozhou oilfield of songliao basin,covers an areaof47.8Km2.Putaohua reservoir is a typical low permeability reservoir. With thecontinuous deepening exploitation, production contradiction is obvious. Based on re-understanding about geological characteristics of this area, development characteristicsare analysed and development effect is evaluated. Eventually, ODP adjustment has beenput forward. The main research results are as follows:1. Through the analysis of logging data, the completely cycle of regression-transgression have been determined on the base of layer division and contrast. PI5mainly deposited inter-distributary channel and mouth bar, and its sand thickness islarge, but is limited in scope. Inter-distributary channel is gradually atrophic in PI3,while mouth bar and sheet sand are widely developed. The lake began to shrink in PI2,with the inter-distributary channel is widely developed.2. Through the analysis of the oil well output status and characteristics of effectiveresponse for water flooding, tectonic and sedimentary microfacies are two main factorsto productivity. Reservoir of high part of structural is good, and the lower part is poor.The inter-distributary channel and mouth bar have large thickness and high productivity,while the sheet sand is relatively poor.3. According to the classification and assessment standard of low permeabilitysandstone reservoir, water flooding producing reserves, energy conservation condition,the residual oil recovery rate of recoverable reserves of old wells, injection rate andmeasures of efficiency are calculated, which determined that the Zhao25-58well areabelongs to the second class level of development.4. Combined the geological characteristics, development characteristics anddevelopment effect, the feasibility studies of technology policy had been carried out.34well measures including new deployment, fracturing, hole filling, transfer, waterblocking, water transfer and other measures has been proposed.