特低渗透扶余油层CO_2驱吸气特征研究

Study on CO_2 Flooding and Suction Characteristics in Very Low Leakage FUYU Reservoir

为搞清注CO_2驱油注入井吸气层位、吸气特征及其影响因素,在储层研究基础上对试验区3口井氧活化测试成果按照成因砂体类型进行分析。采用高分辨率层序地层学与层次分析相结合的方法进行了储层精细研究,按成因将砂体划分为大中型河道砂、小型河道砂和薄层砂三种,明确了各类砂体特征。结合CO_2注入井氧活化测试剖面与数值模拟研究了储层吸气特征及影响因素,认为储层吸气主要为河道砂,以大型河道砂吸气量最大。影响吸气因素主要为砂体规模与储层物性,小型河道和薄层砂层位吸气对主力层大型河道砂储层吸气量有层间干扰影响;应用数值模拟技术研究了注CO_2驱油储层物性下限,搞清了无效砂岩吸气原因。该研究对注CO_2驱油试验区下步工作具有一定指导和借鉴作用。

To make clear inhale horizon,inhale characteristics and its influencing factors of injection Wells in the CO_2 oil displacement experiment,on the basis of fine reservoir research,we analysis Oxygen activation test results of three wells in Test area according to different causes sand types.Using the method of high-resolution sequence stratigraphy and hierarchical analysis to the reservoir fine research,According to causes,the sand is divided into three kinds of large-medium channel sand,small channel sand and thin layer sand,and detailed research on all kinds of sand exhibition cloth characteristics.On this basis,combined with CO_2 injection wells oxygen activation test profile,Application of statistical analysis and numerical simulation technology means detailed analysis of the reservoir inspiratory characteristics and its influencing factors,think of reservoir inspiratory mainly for river channel sedimentary reservoir,especially large channel sand for the largest amount,secondly for small channel sand and thin layer sand.Sand body size and petrophysical property is the main factor of effect inspiratory,Moreover small channel sand and thin-layer sand produce interlayer disturbance effect for large channel sand reservoir inspiratory quantity.Application of numerical simulation technology research the note CO_2 oil displacement petrophysical limit,Clarified the invalid sandstone inspiratory existence reasons.The study for the next steps work of note CO_2 oil displacement suggestions and new open area has certain guidance and reference.