鄂尔多斯盆地北岔沟砂岩沉积特征及其对天然气成藏的控制作用*
黄建松1,2,5, 郑杰1,2, 宋翔1,2,5, 刘磊5, 易刚3,4,5, 杨萍5

Sedimentary characteristics of Beichagou Sandstone in the Lower Permian Shanxi Formation in Ordos Basin and its effects on natural gas accumulation
HUANG Jiansong1,2,5, ZHENG Jie1,2, SONG Xiang1,2,5, LIU Lei5, YI Gang3,4,5, YANG Ping5
鄂尔多斯盆地北岔沟砂岩典型岩性特征 103 A—周至柳叶河(东经: 108°9'36.00″,北纬: 33°58'48.00″),冲积扇扇根大型砾岩体,砾石成分以蓟县系藻白云岩、长城系浅变质石英砂岩和红色浅变质泥岩为主,杂基基底式胶结,砾石呈次圆—次棱角状,砾径1~100 cm,砾石杂乱排列,略具正粒序结构;B—J12井,5-81/96岩心,湿地扇扇中辫状水道砾岩,砾石成分以石英岩和燧石为主,呈次圆状,砾径0.5~5 cm,分选差,磨圆较好,呈叠瓦状定向排列,杂基胶结;C—乌海千里山(东经: 106°59'33.36″,北纬: 39°51'1.44″),大型植物茎干印模;D—乌海千里山,砾质辫状河底砾岩,砾石成分以石英岩和燧石为主,可见变质粉砂岩和成分不明的黑色变质岩类,呈次圆状,砾径2~5 cm,磨圆较好,分选较差,杂基胶结; E—乌海千里山,砾质辫状河沉积复合砂体,由多个单砂体互相切割、紧密叠置而成,每个单砂体可见正粒序结构,发育槽状交错层理