Permian system in Tazhong area may be divided into three lithology groups: lower clastic group, volcanics group and upper clastic group based on the data of core, drilling, logging and so on.

前言： 依据岩心、钻井、测井等资料，将塔中地区二叠系分为三个岩性组：下碎屑岩组、火山岩组、上碎屑岩组。

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A set of intermediate basic volcanics, pyroclastic rock and top part of clastic rock is found in north of Balikun coal mine.

巴里坤煤矿北原划下泥盆统塔黑尔巴斯套组下部，发现一套中基性火山岩及火山碎屑岩建造。

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Volcanics mainly growth gas pocket, primary rift and secondary rift, The secondary porosity of clastic rocks is much more developed.

火山岩储层主要发育气孔、原生裂缝、次生裂缝；碎屑岩则以次生孔隙为主。

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