须家河组二、三段构成了一个“不完整”的三角洲旋回。沉积环境的主要类型包括陆上顶积和部分水下顶积;前者可分为湖泊和湖沼环境;后者仅包括分流河道和分流河口砂坝。 这个“不完整”三角洲旋回的形成主要是受构造运动的控制。 根据野外资料,煤层主要赋存于陆上顶积中。 Xujiahe group two or three paragraphs constitute an “incomplete” delta cycle. The main types of sedimentary environment include the top land and some underwater top land; the former can be divided into lakes and lakes environment; the latter only includes the distributary channel and distributary estuary sand dam. The formation of this “incomplete” delta cycle is dominated by tectonic movements. According to field data, coal seams mainly occur in the top land plot.