特色录井技术在低孔渗储层解释评价中的应用--以陆丰凹陷古近系为例

Application of characteristic mud logging technology in interpretation and evaluation of low porosity and permeability reservoirs:A case study of the Paleogene in Lufeng sag

珠江口盆地陆丰凹陷古近系发育低孔渗储层,此类储层非均质性强,孔隙结构多样,录测井响应特征十分复杂,应用常规方法解释符合率较低.通过研究优选出FLAIR流体录井技术、数字岩屑录井技术以及XRD衍射录井技术,建立一套适用于低孔渗储层的录井技术组合,为低孔渗储层解释评价提供新思路.研究结果表明:应用FLAIR流体录井衍生参数C_(1)异常倍数、FLAIR计算全烃等参数建立解释图板,可以实现对低孔渗储层复杂流体性质的快速评价;应用数字岩屑录井技术,可以快速、实时获得储层的孔隙度、渗透率及三维孔隙结构等关键参数,在实钻过程中提高对储层的认知;利用XRD衍射录井数据,建立填隙物含量指数I_(0),通过与邻井资料进行对比,可以辅助判断储层孔隙连通性.上述特色录井技术在陆丰凹陷低孔渗储层解释评价中取得了较好的应用效果,具有一定的推广意义.

Low porosity and permeability reservoirs are developed in the Paleogene in Lufeng sag of Pearl River Mouth Basin.Such reservoirs have strong heterogeneity,diverse pore structures,complex mud logging and log response characteristics,and low coincidence rate of interpretation by conventional methods.Through research,the technologies of FLAIR fluid logging,digital cuttings logging and XRD logging are optimized,and a set of mud logging technology combination suitable for low porosity and permeability reservoirs is established to provide new ideas for interpretation and evaluation of low porosity and permeability reservoirs.The use of the C_(1) abnormal multiple of FLAIR fluid logging derived parameter and FLAIR calculated total hydrocarbon to establish an interpretation chart can realize the rapid evaluation of complex fluid properties in low porosity and permeability reservoirs.With the use of digital cuttings logging technology,key parameters such as porosity,permeability and three-dimensional pore structure can be obtained quickly and in real time to improve the understandings of the reservoir during drilling process.The interstitial matter content index(I_(0)) was established based on XRD logging data,which can assist in judging the reservoir pore connectivity by comparing with the off-set well data.The above characteristic mud logging technologies have achieved good application results in the interpretation and evaluation of low porosity and permeability reservoirs in Lufeng sag,and are valuable for generalization.