Concentrations From The Early Cambrian Soft-bodied Fossils In The Chengjiang Lagerstätte

The efforts of labor-intense collections in the Early Cambrian Chengjiang Lagerstatte in eastern Yunnan Province lead to the discovery the soft-bodied fossil concentration, which could be regarded as a special status of fossil concentration with peculiar preservation, taphonomy and deposition. Many informations of the interaction between animal and environment were contained in it and it is meaningful to the taphoniomic and paleobiological research work of Chengjiang fauna. Many people have reported the special phenomenon, but unfortunately they did not do further reseach work. Based on the studies of former, the author makes these achievements as follows :l.Jianshan section of Haikou was described in detail in Chapter I.2.Principles,taxonomics and descripton methods of fossil accumulation were introduced in Chapter II.3.The fossil accumulation in Chengjiang Lagerstatte were described in Chapter III. There were two forms of Fossil accumulation in Chengjiang Lagerstatte :fossil aggregation and fossil concentration. The differences of boundary, range and shape between them were very significant. The fossil concentration can be subdivided in to crust concentration and soft-bodied fossil concentration according to the preservation.4.Four soft-bodied fossil concentrations were described in Chapter IV. Horizon, biofabric, rock structure and preservation about soft-bodied fossil concentration of Cricocosmia jinningensis,Haikouella jianshanensis and Stellostomites eumorphus were described in detail. Meticulous discussion on the reasons and processes of their formation were made.5.The feature, otherness, formative reason and the influence factors of soft-bodied fossil concentration in Chengjiang Lagerstatte were discussed in Chapter V, and also draw a conclusion :The features of soft-bodied fossil concentration in Chengjiang Lagerstatte : Soft-bodied preservation;Universality;Monospecific concentration;Storm caused event deposition.Otherness : The space distribution;The situation of preservation.Formative reasons: Palaeoenvironment;Rapid sedimentation of storm induced muddy deposition;The opportunistic species became to the dominant species;Gregarious attribute.Influence factors : Biological attribution;Paleoecology;Depositional process;Taphonomic process.