摘要
为了提高海拉尔盆地乌南凹陷高伽马砂岩测井岩性解释的准确性,采用岩心观察、显微镜下描述和测井曲线分析相结合的方法对高伽马砂岩的成因和识别方法进行探讨。对砂岩的补偿中子值进行分类以排除孔隙度对测井曲线的影响,再利用深侧向电阻率、微侧向电阻率和补偿密度交会识别高自然伽马砂岩。研究结果表明:影响砂岩自然伽马特征的因素有凝灰质、黏土、油、长石以及钙质;高自然伽马砂岩具有高钍或者高铀含量的特征;凝灰质导致钍富集,黏土导致铀、钍和钾均富集,油导致铀富集,长石导致钾富集,钙质导致铀含量降低;从凹陷边缘至凹陷中央影响砂岩高自然伽马因素依次为高凝灰质含量、高长石含量以及高黏土含量。
In order to improve the accuracy of logging lithology identification of high natural gamma sandstone in Wunau depression in Hailar Basin, in terms of rock core and microscopic sections description and logging analysis, the causes and identification of high gamma sandstones were discussed. The classification of the sandstone CNL values can provide a estima- ting under a certain porosity degree. The high natural gamma sandstones can be identified using deep lateral resistivity （DLL）, micro lateral resistivity logging（ RMLL）, DEN and AC. The researeh results show that the factors affecting these sandstones with high natural gamma are tuffaceous matter, clay, oil, feldspar and calcium. High natural gamma sandstones express high content of thorium or uranium from logging data. The tuffaceous matter leads to the enrichment of thorium, clay leads to the enrichment of uranium, thorium and potassium, oil leads to the enrichment of uranium, feldspar leads to the en- richment of potassium, and calcareous matter leads to the decrease of uranium content. The affecting factors of sandstone na- tm＇e gamma ray are high tuffaceous matter, high feldspar and high clay ranging from edge to center of the depression.
出处
《中国石油大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2012年第3期76-83,共8页
Journal of China University of Petroleum(Edition of Natural Science)
基金
国家自然科学基金项目(40972074)
吉林大学平台基地建设项目(450060326044)
关键词
海拉尔盆地
乌南凹陷
高自然伽马砂岩
岩石成因
识别方法
Hailaer Basin
Wunan depression
high natural gamma sandstone
lithogenesis
recognition method
