苏北盆地致密砂岩油藏气测录井评价方法

Gas logging evaluation methods for tight sandstone reservoir in Subei Basin

致密砂岩油藏气测录井测量结果只与烃类物质丰度有关,受储集层四性关系的影响较小,在致密砂岩油藏评价解释中起到一种不可替代的作用,为此,展开了对苏北盆地致密砂岩油藏气测录井解释方法的研究。针对致密砂岩油藏,结合苏北盆地地质特征,首先运用钻时法、全烃曲线特征法及纵向趋势判别法进行油藏的定性评价;然后统计研究区12口井100余层气测录井资料,结合试油结果,分析建立了气体轻重比值法和能量系数法的定量解释图板,认为两种图板能有效地划分出油层、干层,并与定性解释相互验证、相互补充。研究区已试油的5口井的验证结果表明,该综合评价方法与试油资料吻合较好。

Gas logging measurement results for tight sandstone reservoirs are only related to the hydrocarbons abundance and are less affected by the four properties of reservoirs,which play an irreplaceable role in the interpretation and evaluation of tight sandstone reservoirs,thus the research of gas logging interpretation method was carried out for the tight sandstone reservoirs in Subei Basin.For tight sandstone reservoirs,the qualitative evaluation of reservoirs was first made with geological features of Subei Basin,drilling time method,total hydrocarbon curve characteristic method and longitudinal trend discrimination method,then the statistical gas logging data were got from more than 100 layers of 12 wells in the study area,the quantitative interpretation charts of the gas weight ratio method and energy coefficient method were established with oil test results.These two charts can effectively divide oil layers and dry layers,and can mutually verify and complement with qualitative interpretation.The validation results from five oil tested wells in the study area indicated that the comprehensive evaluation method agreeed with the oil test data.