甘肃大泉水——白沙岘矿区含煤地层及煤层赋存特征

大泉水-白沙岘矿区位于甘肃省景泰县境内，在大地构造位置上处于北祁连加里东褶皱带东段，区内含煤地层为下石炭统靖远组和上石炭统羊虎沟组，属海陆交互相含煤沉积，根据岩性、岩相特征可划分为两个沉积旋回。该矿区主要可采煤层煤．层组赋存于羊虎沟组，厚1．71～9．00m，沿走向由西向东厚度变小，在大泉水井田可采厚度主要分布在V线以西，其东区段只是零星分布且不可采；在白沙岘井田煤层总厚度为2．99～5．15m，厚度变化小，属稳定煤层。煤：层组赋存于靖远组，仅分布在大泉水井田，厚1．33～8．88m，沿走向由西向东呈长透镜体状，西段和中段煤层发育较好．V线以东区段煤层变薄并出现无煤区。

Coal-bearing Strata and Coal Seam Hosting Characteristics in Daquanshui-Baishaxian Mining Area,Gansu

The Daquanshui-Baishaxian mining area is in the Jingtai County, Gansu Province, tectonically it is situated on the eastern sector of the Northern Qilian Caledonian folded belt. The coal-beating strata in the area are Lower Carboniferous Jingyuan Formation and Upper Carboniferous Yangbugon Formation, both alternative marine-terrestrial deposits. Two depositional cycles can be divided according to lithology and lithofacies. The main mineable coal seam M1 is hosted in the Yangbugou Formation, 1.71-9.00m thick, along the strike from west to east getting thinner, in the Daquanshui minefield, workable thickness is mainly distributed to the west of the V exploratory line, while to the east only sporadic distributed and nonmineable; in Baishaxian minefield, total coal seam thickness is 2.99-5.15m with little thickness changing, belongs to stable coal seam. Coal seam M2 is hosted in the Jingyuan Formation, distributed in Daquanshui minefield only, 1.33-8.88m thick, along the strike from west to east is presented a shape of long spectacle lens, coal seam is well developed in western and middle sectors, to the east of V exploratory line is getting thinner and barren area presented.