以塔木查格盆地火山碎屑岩为研究对象,通过不同温度下大气水—火山碎屑岩相互作用的水热实验研究发现,大气水能够使火山碎屑岩中的长石、方解石等可溶性矿物发生溶蚀,且溶蚀强度随温度升高而加大；火山碎屑岩中的凝灰质成分容易发生溶蚀,而且是主要溶蚀对象.通过塔南凹陷铜钵庙组不整合面之下的储层物性研究发现,在不整合面之下30m范围内,大气水淋滤作用对火山碎屑岩储层物性改善明显,孔隙度增加量达5％～14％,次生孔隙所占比例达88.48％-95.00％;而在不整合面之下80m以外的范围,大气水淋滤作用对储层物性基本没有影响.大气水淋滤作用是塔南凹陷铜钵庙组次生孔隙形成的主要原因,作用的下限深度为不整合面之下30～80m.%The volcanic clastic rocks from the Tamtsag Basin were studied. The experiments of atmospheric water and volcanic clastic rock reaction were conducted under different temperatures. It has been concluded that the soluble minerals in volcanic clastic rocks, such as feldspar and calcite, can be dissolved by atmospheric water, and the dissolution intensity will be enhanced with the increasing of temperature. Tuff in volcanic clastic rocks could be dissolved easily and is the main dissolution mineral. The researches of reservoir properties in the Southern Tamtsag Sag showed that within 30 m beneath the unconformity surface of the Tongbomiao Formation, the physical properties of reservoir were improved obviously by the eluviations of atmospheric water. Porosities increased by 5% -14% and the secondary porosities accounted for 88.48% -95.00%. There was no effect away from the scope of 80 m. The eluviations of atmospheric water play the main contribution to the secondary porosity formed in the Tongbomiao Formation of the Southern Tamtsag Sag, and the lowest limit is 30 to 80 m below unconformity surface.
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