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雅鲁藏布江缝合带中自西向东分布着二叠纪灰岩块体,被称为西藏相灰岩外来块体或奇底宗型的二叠系。姜叶玛灰岩是其中之一,位于西藏西部普兰县境内。■类动物群是该灰岩块体中最丰富的生物群之一,其中瓜德鲁普统西兰塔组的■类有10个属,分别为Neoschwagerina,Yangchienia,Armenina,Verbeekina,Paraver-beekina,Kahlerina,Lantschichites,Codonofusiella,Chusenella,Nankinella。Kahlerina,Lantschichites和Codono-fusiella的存在表明西兰塔组■类动物群的时代为Midian期(Guadalupian世晚期),相当于华南的冷坞期。姜叶玛灰岩和仲巴县拉赛拉灰岩、阿曼Batain地区以及巴基斯坦盐岭地区一样,Midian期■类动物群缺少Afghanella-Sumatrina组合,结合当时古地理位置认为,这几个地区处于相对较凉水温控制之中。
The Permian limestone blocks are distributed from west to east in the Yarlung Zangbo suture zone, and are known as Permian blocks or Chiidongzong type Permian blocks in Tibet. Ginger leaf limestone is one of them, located in western Pulan County. ■ The fauna is one of the most abundant biota in the limestone block. Among them, there are 10 genera in the Guadeloupe-Xilantha Formation, Neoschwagerina, Yangchienia, Armenina, Verbeekina, Paraver-beekina , Kahlerina, Lantschichites, Codonofusiella, Chusenella, Nankinella. The presence of Kahlerina, Lantschichites and Codono-fusiella suggests that the age of the Cataract fauna in the Galata Formation is the Midian (late Guadalupian) phase, equivalent to the cold-dock period of southern China. The Jiangian magmatic limestone is similar to the Lhasa Limestone in Zhongba County, the Batain region in Oman and the Yanling region in Pakistan. The Midian fauna lacked the Afghanella-Sumatrina assemblage. In the light of the palaeoclimatic position of the time, these regions were in relative Cold water temperature control.