灰质泥岩特征及测井响应--以胜坨地区沙三下亚段为例

摘要

It is with complex spatio-temporal distribution of turbidite and deltaic deposit body of Sha 3 lower sub-interval in Shengtuo area,and great distribution of calcareous clay has made great influence on sedimentary system space description.In order to make better study of this type of sedimentary system,base on conventional well log data,core observation,thin section authentication and XRF(X-ray fluorescence)element test,and starts from the rock type analysis of rich grey matter mudstone in Sha 3 lower subinterval,this paper makes a conclusion on the calcareous clay characteristics and log response of different sizes.It divides the different rock types combination and establishes the logging response mode.The results show that the dark gray lime mudstone is with a low GR and medium AC characteristics,and sandy mudstone and dark gray mudstone show a high GR and high AC.The GR average value of sandy mudstone is greater than dark gray mudstone,while the seismic transit time deviation is low. The rocks in study area are divided into four types of calcareous clay-sandstone-type,mudstone-sandstone-type,cal-careous clay-pelitic rock type and calcareous clay-conglomerate type,establishing the corresponding log interpreta-tion model.%胜利油田某地区沙三下亚段浊积岩、三角洲沉积体时空展布复杂，大量分布的灰质泥岩对沉积体系空间描述造成了影响。为更好地对该类沉积体系进行研究，基于常规测井资料、岩心观察、薄片鉴定及 XRF(X-ray fluorescence)元素测试等资料，从沙三下亚段富灰质泥岩岩石类型分析入手，对不同尺度灰质泥岩岩石学及测井响应特征进行了总结，划分不同的岩石类型组合并建立了测井响应模式。研究结果表明，深灰色灰质泥岩具有低 GR(自然伽马)中 AC(声波时差)特征，砂质泥岩及深灰色泥岩呈现高 GR、高 AC 特征。砂质泥岩的 GR 均值大于深灰色泥岩，而声波时差值则偏低。研究区岩石划分为灰质泥岩—砂岩型、泥岩—砂岩型、灰质泥岩—泥岩型、灰质泥岩—砾岩型四种类型，建立了相应的测井解释模型。