随钻方位伽马测井仪器的优化设计  

Optimization design of azimuthal gamma logging instrument while drilling

作　　者：李梦婷 吴文圣[1] 郑奕挺[2] 张卫[2] 贺柳琼 曲汉武 LI Meng-ting;WU Wen-sheng;ZHENG Yi-ting;ZHANG Wei;HE Liu-qiong;QU Han-wu(State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China;Sinopec Research Institute of Petroleum Engineering,Beijing 100101,China;Well Tech of China Oilfield Services Limited,Yanjiao 065201,China)

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油化工股份有限公司石油工程技术研究院,北京100101 [3]中海油田服务股份有限公司油田技术事业部,燕郊065201

出　　处：《地球物理学进展》2020年第1期313-321,共9页Progress in Geophysics

基　　金：国家科技重大专项(2016ZX05021)资助.

摘　　要：随钻方位伽马测井仪器能在钻井过程中有效测量地层的方位放射性强度,其测量效率与其结构参数有关.合理设计测井仪器的结构参数,可以大大提高其测量效率.利用蒙特卡罗数值模拟方法建立模型,从归一化统计误差和探测特性分析仪器的响应特征,为结构参数的选取提供理论依据.研究结果表明,6.75 in(1 in=2.54 cm)的钻铤外径下,当晶体直径为1 in左右,晶体长度为18~22 cm,屏蔽体长度为2~3 cm,屏蔽体厚度为2~3 cm,窗口材料为铍,屏蔽体开口角度选在0°附近,泥浆通道半径为2 cm左右时,仪器可以获得相对较低的统计误差和相对较好的探测特性.该研究表明,优化后的随钻方位伽马测井仪器的测量效率大大提高.The azimuthal gamma logging while drilling can provide real-time lithology information and guide the drill bit to drill into the target formation smoothly.Improving the measurement efficiency of the instrument becomes a difficult point of instrument design,so it is of great significance to the optimization design of the instrument.The azimuthal gamma logging instrument can effectively measure the azimuthal radioactivity of the formation during the drilling process,and its measurement efficiency is related to its structural parameters.Reasonable design of logging instrument structural parameters can greatly improve its measurement efficiency.The model is established by Monte Carlo numerical simulation method.The response characteristics of the instrument are analyzed from normalized statistical error and detection characteristics,which provides a theoretical basis for the selection of structural parameters.The research results show that under the outer diameter of the 6.75 in drill collar,when the crystal diameter is about 1 in,the crystal length is 18~22 cm,the length of the shield is 2~3 cm,and the thickness of the shield is 2~3 cm,window material is beryllium,the opening angle of the shield is chosen to be around 0°,and the radius of the mud channel is about 2 cm,the instrument can obtain relatively low statistical error and relatively good detection characteristics.This study shows that the measurement efficiency of the optimized azimuthal gamma logging instrument is greatly improved.

关 键 词：MC模拟 随钻测井 方位伽马 优化设计 

分 类 号：P631[天文地球—地质矿产勘探]