百色盆地致密储层钻井液污染测井评价及应用

百色盆地东部坳陷中央凹陷带那读组储层具有低孔隙度低渗透率特征,一直缺乏有效评价该地区储层泥浆污染程度的方法.首先通过研究泥浆侵入对电阻率测井的影响,理论推导了一种直接利用深、中、浅电阻率组合测井资料计算泥浆侵入深度的方法,并根据泥浆污染深度与泥浆侵入深度的关系式,得到储层泥浆污染程度评价定量指标;其次分析储层产量和物性参数的相关程度,建立了储层产量和物性参数间的定量计算模型,间接地实现了储层泥浆污染程度的定量评价,形成了一套用测井资料评价储层泥浆污染程度方法,为科学钻井的实施提供了重要依据.经实钻结果验证,所建立的评价方法有效可行,取得了良好的经济效益,具有明显实用价值.

Log Evaluation Method of Tight Reservoir Pollution Level by Drilling Fluid and It's Application in Baise Basin

Nadu formation reservoir of centre depression in the East col of Baise basin is a conti-nental clastic deposit, which has low porosity and permeability properties. For a long time, it lacked of effective method to evaluate reservoir pollution level. Firstly, according to the analysis of the effect of drilling fluid invasion or resistivity logging, in theory, proposed is a method for calculating mud invasion depth by deep-, medium-and shallow-investigation resistivity combina-tion logging data, and according to the relation formula of mud pollution depth and mud invasion depth, the indexes of reservoir pollution quantitative evaluation is obtained. Secondly, analyzed is the correlation degree between the productivity and parameters of the reservoir property, the quantitative calculating model is developed between the productivity and mainly parameters of the reservoir. Reservoir pollution quantitative evaluation is achieved indirectly. Formed is a set of method of evaluation reservoir pollution degree by logging data, which offers important reference for drilling well. Practical drilling well results show that the evaluation method is effect, a great economic benefit has gained, so this method has obvious application value.