二连盆地伊和高勒地区下白垩统赛汉组沉积特征

Sedimentary Feature of Early Creatacous Saihan Formation in Yihegaole Area of Erlian Basin

为揭示二连盆地马尼特坳陷伊和高勒地区下白垩统赛汉组沉积特征,文章通过综合分析研究区内露头剖面、钻孔等,较为精细地研究了赛汉组岩性特征、地层空间展布特征、底板埋深分布特征、沉积相类型、沉积相展布特征等。研究区赛汉组分布范围广,具有东厚西薄的格局。底板埋深东部深西部浅,西部发育构造斜坡。西部为砂岩与泥岩,砂岩富炭屑;东部为砂砾岩与泥岩,砂砾岩中含炭屑。发育南、北两个方向物源,北部物源占主导作用。西部发育辫状河三角洲,砂体发育,"泥-砂-泥"结构好,为砂岩型铀矿最有利的沉积相带;东部发育扇三角洲,砂体极为发育,"泥-砂-泥"结构较好,为砂岩型铀矿较为有利的沉积相带;中部为半深湖-滨浅湖,砂体不发育,不利于砂岩型铀成矿。

To reveal the features of the Eearly Crataceous Saihan Formation in Yihegale area of the Manite depression,Erlian Basin,the paper studied the detail lithologic character,strata distribution,backplane buried depth,sedimentation types,sedimentation distribution,et al.by synthesis outcrop and drills rock observation.The Saiham Formation was wide in area,thick in the east and thin in the west,buried deep in the east and shallow in the west with monocline developed.The rocks in west are sandstone and mudstone rich in carbon debris,in the east are glutenite and mudstone and some carbon debris in glutenite.There are north and south provenance in the depression,sources from the north provided the main sediments.In the west,the braid river delta was developed and‘mudstone-sandstone-mudstone’combination was formed,which provide favorite condition for the sandstone type uranium deposit.The fan delta was developed in the east which produced excellent sand and preferable‘mudstone-sandstone-mudstone’combination,which provide better sedimentary facie for sandstone type uranium deposit.In the center,massive mudstone of semi abyss-shallow lacustrine deposited which is not favorable for sandstone uranium mineralization.