自然伽马测井在阻溶剂界面精细判断中的应用

Application of Natural Gamma Logging in Fine Determination of Resistance and Solvent Interface

自然伽马测井曲线和特征对岩性以及泥质含量等十分敏感,近井地带半径50cm内的岩层对伽马测井曲线贡献达到99%,伽马测井可以准确反映地层近井地带的地层情况。分析盐穴储气库6口井水溶造腔过程中的伽马测井曲线发现,阻溶剂界面上移后裸眼段受到水侵溶蚀,即使在溶蚀很小一部分的情况下,测井曲线上伽马值也会迅速减小,根据这一现象可判断水溶造腔过程中阻溶剂界面的变化情况。根据伽马测井原理,推导出阻溶剂界面上移后裸眼段的溶蚀半径,并结合现场数据,验证了溶蚀半径计算模型的准确性,计算方法可判断岩穴储气库造腔过程中的阻溶剂界面变化情况。

The natural gamma logging curve and characteristics are very sensitive to lithology and mud content,and the rock formation within 50cm radius of the near-well zone contributes 99%to the gamma logging curve.Gamma logging can accurately reflect the formation conditions of the near-well zone.Analysis of 6 mouth well water soluble salt cavity gas storage built cavity gamma logging curve is found in the process of solvent resistance interface up after the open hole section water invasion dissolution,even in a tiny part of dissolution case,log on gamma value will decrease rapidly,according to this phenomenon judgment made cavity in the process of water soluble solvent resistance changes of the interface.