Preliminary Study of Taphonomic Environment of Luoping Biota: Evidence from sedimentary structures

Key words: 
• Luoping Biota

Abstract: The Luoping Biota is contained in the Member Ⅱ of the Ainsian Guanling Formation at Dawazi Village, Luoping County, Yunnan Province, China. It is characterized by abundant wellpreserved marine ichthyofauna , associated with marine reptiles, echinoderms, crustaceans, bivalves and plant fossils. The strata bearing the Luoping Biota are dominated by gray black thin bedded micrite as well as a large number of sedimentary structrues, such as horizontal laminae, wavy bedding, deformation structures (slump structures, convolute bedding) and trace fossils and so on. This paper aims to study the sedimentary environment and taphonomy of the Luoping Biota. The result shows that the sedimentary environment of Luoping Biota is a deep water basin with distally steepened ramp on the platform. The sea water in this basin was relatively quiet with intermittent reducing condition which effectively prevented the degradation of organisms. The sedimentary deformation structures on distally steepened ramp indicate that the environment was changed suddenly, which led to the demise and the rapid burial of the biota.