四川盆地晚二叠世吴家坪期岩相古地理

四川盆地上二叠统吴家坪阶岩石类型多样，按岩性及岩相特征的不同，吴家坪阶可划分为4种类 型，即峨眉山玄武岩组火山岩、宣威组陆相碎屑岩，龙潭组海陆过渡相碎屑岩以及吴家坪组海相石灰岩，横向 上岩性变化明显。在对露头和钻井剖面单因素定量及定性资料分析的基础上，采用单因素分析多因素综合作图 法，对四川盆地晚二叠世吴家坪期的岩相古地理进行了研究及编图。吴家坪期总体上自西南向东北依次展布剥 蚀区、冲积平原、碎屑岩台地、碳酸盐岩台地、斜坡(过渡带)和盆地，其中碳酸盐岩台地内局部发育低能生 屑滩。四川盆地吴家坪期成煤环境多样，三角洲、湖-海湾及潮坪相成为煤层发育的主要相带，这些环境中 的暗色泥岩、页岩及煤，为吴家坪阶重要的烃源岩，碳酸盐岩台地环境中的石灰岩也可以作为吴家坪阶主要储 集岩。

Lithofacies palaeogeography of the Late Permian Wujiaping Age of Sichuan Basin

The rock types of the Upper Permian Wujiaping Stage are variable in the Sichuan Basin. According to lithology and lithofacies characteristics,four main rock types of the Wujiaping Stage can be classified as follows:volcanic rocks of the Emeishan Basalt Formation,continental clastic rocks of the Xuanwei Formation,marine-continental transitional facies clastic rocks of the Longtan Formation and marine carbonates of the Wujiaping Formation,which changed obviously and regularly from west to east. Based on the q...