南堡凹陷中深层储集层气测参数特征及解释评价

Characteristics and interpretation-evaluation of gas logging parameters for middle and deep reservoirs in Nanpu sag

冀东油田南堡凹陷中深层东营组一段(东一段)、东营组三段(东三段)、沙河街组一段(沙一段)的气测参数响应特征不一致、钻探过程中多采用咸水钻井液进行钻探以及测井参数难以准确评价储集层,造成该地区储集层解释评价的难度增大。为提高该地区解释的精度,系统分析南堡凹陷1-5号构造中深层各含油层系的气测数据组分响应特征,经过已钻38口井48层段数据统计,筛选出了烃斜率、湿度比、平衡比、特征比4项气测敏感参数,建立东一段、东三段、沙一段含油层系气测解释评价图板,从图板中发现油层湿度比的区间东一段为13.53%~42.31%、东三段为17.26%~25.00%,沙一段为12.17%~20.91%;油层烃斜率的区间东一段为0.62~3.25、东三段为0.76~1.72,沙一段为1.53~2.80;油层平衡比的区间东一段为1.26~18.08、东三段为5.03~14.75,沙一段为10.11~19.64;油层特征比的区间东一段为0.14~1.67、东三段为0.33~0.60,沙一段为0.27~0.55。据此建立了相应的评价标准,现场应用实例表明该方法评价效果较好,可以为勘探评价提供重要的依据。

The response characteristics of gas logging parameters in member 1 of Dongying formation,member 3 of Dongying formation and member 1 of Shahejie formation in the middle and deep reservoirs of Nanpu sag of Jidong Oilfield are inconsistent.In addition,salt-water drilling fluid is mostly used in the drilling process,so it is difficult to accurately evaluate the reservoirs with log parameters,which makes the reservoir interpretation and evaluation in this area more difficult.In order to improve the accuracy of interpretation in this area,the component response characteristics of gas measured data of various oil-bearing strata in the deep layers of structures 1 to 5 in Nanpu sag were analyzed systematically.Based on the data statistics of 48 intervals of 38 wells drilled,four sensitive parameters of hydrocarbon slope,humidity ratio,equilibrium ratio and characteristic ratio were screened out.The gas logging interpretation and evaluation charts for the oil-bearing series in member 1 of Dongying formation,member 3 of Dongying formation,and member 1 of Shahejie formation were established.Seen from the charts,the oil layer humidity ratio ranges from 13.53%to 42.31%in member 1 of Dongying formation,17.26%to 25.00%in member 3 of Dongying formation,and 12.17%to 20.91%in member 1 of Shahejie formation.The oil layer hydrocarbon slope ranges from 0.62 to 3.25 in member 1 of Dongying formation,0.76 to 1.72 in member 3 of Dongying formation,and 1.53 to 2.80 in member 1 of Shahejie formation.The oil layer equilibrium ratio ranges from 1.26 to 18.08 in member 1 of Dongying formation,5.03 to 14.75 in member 3 of Dongying formation,and 10.11 to 19.64 in member 1 of Shahejie formation.The oil layer characteristic ratio ranges from 0.14 to 1.67 in member 1 of Dongying formation,0.33 to 0.60 in member 3 of Dongying formation,and 0.27 to 0.55 in member 1 of Shahejie formation.Based on this,the corresponding evaluation criteria were established.The field application shows that the method has good evaluation effects and can provide an important basis for exploration evaluation.