沁水煤田町店勘探区太原组K_2－K_4灰岩段沉积环境

Sedimentary Environment of K_2-K_4Environment of K_2-K_4 Limestone Member of Taiyuan Formation in Souteaorst Qinshui Coalfield,Shanxi

Ｋ＿２－Ｋ＿４灰岩段地层发育在上石炭统太原组下部，由灰岩、砂岩、粉砂岩及泥岩互层的细粒沉积物以及煤组成。根据宏观沉积特征和微观显微结构的研究，笔者确定了该段沉积物形成于半局限海的潮汐环境。Ｋ＿２灰岩和Ｋ＿３灰岩为生物碎屑泥晶灰岩，代表了潮下带沉积；Ｋ＿４灰岩为含生物碎屑泥晶灰岩，属潮间带沉积物。该层段内的碎屑岩也属潮间带沉积物，其中砂岩为潮渠成因。该段地层中发育的３层煤由于受潮汐作用的影响，沉积厚度小，煤质差，达不到工业要求。

Qinshui coalfield is located in the southeast part of Shanxi province,North China. TheK_2 laimestone Member was deposited in the lower part of Upper Carboniferous TaiyuanFormation. It consists of limestone,sandstone,siltstone, mudstone and coal.Based on fieldobservation and microscopic research,the author believed that the Member was formed in atidal environment of semi-restricted sea.K_2-limestone and K_3-limestone are bioclastic and mi-critic limestones,and deposited in sub-tidal zone,K_4-limestone and other clastic rocks de-posited in intertidal zone,The coal seams were frequently influenced by tide,and thereforetheir thicknesses are less,and their qualities are poor.