Study On Accumulation Condition Of Fuyu Reservoir In Shuangcheng Area & Optimized Selection Of Hydrocarbon Enriched Area

The working area of interest is located in the south of Well Shuang 30,operated by DaQing Oilfield Company.This area,as recently submitted proved reserve area,is mainly developed in Fuyu formation,where ninety-eight exploratory and appraisal wells have been drilled targeting the several well blocks in north and central part of interest area.The area of interest consists of three seismic working area,covering 830 square kilometers.In order to further identify the accumulation mechanism and hydrocarbon enriched area and cater for the requirements of proved reserve submitting,the high resolution sequence stratigraphic method was used to make a fine stratigraphic division and correlation on principal reservoir F?and F? based on geologic study.Heavy mineral and depositional environment analysis were used to determine the depositional system and sedimentary micro-facies type.According to the accurate interpretation of subzone and sandbody for developed areas,the spreading characteristic of distributary channel sandbody at different stage was clearly defined.When establishing the Fuyu formation comprehensive classification standards,the reservoir petrophysics,microscopic properties,electrical logs,radioactivity logs and other well testing data were used in analysis.From the known reservoir analysis,the reservoirs found in the interest area evaluated herein are grouped into 4 types,primarily including structural reservoir,lithologic reservoir,fault-lithologic reservoir and structural-lithologic reservoir.For exploratory and appraisal wells drilled in appraisal blocks,the net pay thickness was reclassified,based on which 77 pay zones for the existing 33 wells were recognized.For 5 pay zones,the well test was proposed.Together with the comprehensive analysis of hydrocarbon resource rock,reservoir properties and accumulation condition,five favorable development areas were located with an estimate of OOIP of 56,28 million tons,where 11 appraisal wells were deployed,of which 5 wells were completed with drilling success rate of 80%,providing a prophase preparation for the reporting of proved reserves at the later stage of development of Fuyu formation.