The bitumen layer of Y Oilfield in the Middle East is characterized by strong plasticity and poor borehole stability.When bitumen is immersed into the wellbore,drilling efficiency is reduced,w hich limits the development efficiency of the carbonate reservoir.T his paper compares the differences of geological features and logs response between conventional carbonate reservoir and the bitumen intervals,it also discusses the methodology used to distinguish the heavy oil bitumen from the solid and semi-solid(no flow)bitumen.The combination of the core and test data as well as log response analyses highlights that the typical bitumen interval has high clay contents and natural gamma, low uranium free gamma, and poor permeability. Those characteristics and GR-KT H intersection can be used together to identify the bitumen intervals. Moreover,Poisson's ratio,P-wave velocity ratio,and wave impedance calculated by dipole sonic logging can effectively distinguish heavy oil and non-liquid bitumen reservoirs.Based on the log interpretation result and the regional structure analysis,the cause and distribution characteristics of the bitumen layer can be predicted T he logging evaluation technology effectively solves the problem of identification and distribution of bitumen layer in the study area,and provides logging support for development and drilling safety of carbonate reservoir.%中东Y油田沥青层塑性强、井壁稳定性差.沥青浸入井筒后降低了钻井效率,制约了该碳酸盐岩油藏的开发效率.对比常规碳酸盐岩储层与沥青层特征,并对比分析固态、半固态与液态稠油3种沥青赋存状态储层的测井响应特征,结合岩心、测试资料分析结果,认为典型沥青层黏土含量较高、渗透性较差,具有高自然伽马、低无铀伽马测井响应特征,结合 GR—GRKTh交会法可对沥青层进行初步判识.利用偶极声波测井计算的泊松比、纵横波速度比以及波阻抗可有效区分液态稠油与非液态沥青储层.利用测井资料精细处理结果,结合区域构造特征,对沥青层的成因与分布特点进行探索.沥青层测井评价技术有效解决了研究区沥青层识别与分布问题,为碳酸盐岩油藏开发与钻井工程安全提供了测井技术支撑.
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