摘要
分布于石炭纪断陷盆地中的下石炭统马鞍桥组沉积火山岩系,底部为巨砾岩、砾岩、砂砾岩和砂岩,往上逐渐变为砂岩-粉砂岩-页岩互层夹灰岩、基性火山熔岩和少量流纹岩,具有由陆相变为海相,由浅变深、由粗变细的完整拉伸环境沉积充填序列。是碰撞造山阶段中—晚期后陆拉伸的地质记录,标志着早石炭世天山古生代洋盆闭合后,天山造山带已处于陆内构造体制。
The Carboniferous basin represented by Ma'anqiao Formation is a fault basin which formed by backland extension during the middle-late stage of collisional orogeny of Early Carboniferous. The lower sequence is composed of coarse clastic rocks which are pebblestone, gravelstone and sandstone. The upper sequence is composed of finer clastic rocks which are sandstone, siltstone, shale and limestone, implying an extensional setting and facies change from non-marine to marine. Ma'anqiao Formation indicated that the Paleozoic ocean was closed during Early Carboniferous and Tianshan mountains entered an intraplate evolution stage.
出处
《新疆地质》
CAS
CSCD
2002年第4期338-341,共4页
Xinjiang Geology
基金
中国地质调查局国土资源大调查项目(200113000022)资助
