松辽盆地北部火山岩岩相与测井相关系研究

松辽盆地北部火山岩是最主要的天然气储集岩，可分5相15亚相，钻井均有揭示。主要储集岩岩相测井特征为：爆发相热碎屑流亚相高伽玛、低振幅齿形,中-高阻、低频低振幅齿形且下部振幅增大;喷溢相上部亚相高伽玛、高振幅齿形,中-中高阻值、指状或峰状;侵出相内带亚相高伽玛、中振幅齿形,中高-高阻，中振幅齿形。此外，隐爆角砾岩亚相和外带亚相是较好的储层。气层使电阻率明显增大，气水同层一般也使电阻率增大，水层使电阻率减小。不含流体的火山岩电阻率变化规律为：火山沉积相＜侵出相＜爆发相＜火山通道相＜喷溢相；凝灰岩＜熔岩。

Relationship Between Lithofacies and Logging Facies of the Volcanic Reservoir Rocks in Songliao Basin

The Mesozoic volcanic rocks are the most important gas reservoir in the northern Songliao Basin. 5 lithofacies and 15 sub facies have been recognized in the volcanics. The best reservoirs were generally found in three of the fifteen sub facies including pyroclastic bearing lava flow（Ⅱ₃）, upper effusive（Ⅲ₃） and inner extrusive（Ⅳ₁）sub facies. The corresponding logging characteristics are as follows: the Ⅱ₃ is characterized by high value of Gama Ray (GR) with low amplitude dentiform outline, and by media high value of Dual Lateral Logging of Resistivity (DLL) with low frequency and low amplitude dentiform outline; the Ⅲ₃ is high in GR with low amplitude dentiform shape, DLL value of the Ⅲ₃ is media media high and with shapes of finger or hill figure; the Ⅳ₁ shows high value of GR with media amplitude dentiform shape, its DLL is media high high value with media amplitude dentiform shape. Besides, underground explosive breccia facies（Ⅰ₃）and outer extrusive facies（Ⅳ₃）can also be good reservoirs. Gas can cause DLL of the reservoir volcanics increasing markedly but water does the contrary. The DLL of dry volcanic rocks indicates facies and rock type dependent, in the sequence of volcano genitic sedimentary facies＜extrusive facies＜explosive facies＜volcanic vent facies＜effusive facies; tuff＜lava.