云南石林世界地质公园阿诗玛石柱碳酸盐岩显微特征及沉积环境

Microfeatures and Sedimentary Environments of the Carbonates from the Ashima Stele in Shilin World Geopark,Yunnan,China

云南石林世界地质公园阿诗玛石柱,其岩石地层是呈水平产状的中二叠统茅口组厚层块状灰岩,但其构成岩石的具体岩性却未见做过详细工作。笔者等经公园管理部门同意,自下而上分别在阿诗玛石柱背侧底部、下部、中部、上部和顶部共采集样品五块,对其岩石学特征及沉积微相作了详细研究,弄清了这一世界著名景点自下而上的岩石构成及沉积相。底部为高能浅滩相灰色厚层块状具平行层理生屑颗粒灰岩,构成阿诗玛脚部。下部为中能浅潮下灰色厚层块状虫筳生屑泥粒灰岩,构成阿诗玛腿部。中部为中能浅潮下灰色厚层块状砂屑泥粒灰岩,构成阿诗玛腰部。上部为中能浅潮下灰色厚层块状具生物扰动含砂屑生屑泥粒灰岩,构成阿诗玛胸部;顶部为高能浅滩相灰色厚层块状砂屑生屑颗粒灰岩,构成阿诗玛头部。其中含有大量生物化石碎屑:有孔虫、三叶虫、藻类、介形虫、腕足、苔藓虫、虫筳、海百合茎、双壳类,为高能浅滩相和中等能量浅潮下环境。希能为石林形成过程研究和科学普及提供参考。

Horizontal thick bedded limestones of Palaeozoic Permian Maokou Formation that build the Worldwide known scenery Ashima （means a beautiful girl） stele in the Shilin （means stone forest） World Geopark,Yunnan,China.The writers got 5 rock samples from the inconspicuous place of the stele （being allowed by the Geopark）,respectively from the base part,lower part,middle part,upper part and top part.More studies focus on the micro carbonates characteristics and the sedimentary environments.Finally the writers uncover the micro carbonates and the sedimentary environment of the whole stele,from the bottom to the top of this world-wide known of Ashima stele.The base is made of high-energy shoal facies of grey thick bedded grainstones with bioclasts and parallel beddings.That built Ashima＇ s feet.The lower part is made of middle-energy shallow subtidal facies of grey thick bedded packstones with bioclasts of Fusulinida.That builds Ashima＇ s leg.The middle part is made of middle-energy shallow subtidal facies of grey thick bedded packstones with intraclasts.That builds the Ashima＇ s waist.The upper part is made of middle energy shallow subtidal facies of grey thick bedded packstones with intraclasts and bioclasts,or bioturbation structure.That builds Ashima＇ s breast.The top is made of high-energy shoal facies of grey thick bedded grainstones with intraclasts and bioclasts.That builds Ashima＇ s head.The carbonates contained amount of bioclasts,like foraminifera,trilobite,alga,Ostracoda,brachiopod,bryozoansea moss,Fusulinida,crinoid,bivalve.The sedimentary environments are high-energy shoal and middle-energy shallow subtidal.