A new discovery of macroscopic fossils from the Ediacaran Doushantuo Formation in the Yangtze Gorges area

摘要

Two new horizons with macroscopic fossils are reported in the Doushantuo Formation, Ediacaran System, from the Yangtze Gorges area. The fossils were discovered in the lower and middle black shales of the Doushantuo Formation in the new section at Sandouping Town, Zigui County, Hubei Province. The new macroscopic assemblages include Chuaria and Tawuia, and occur below the well-known "Miaohe Biota". These fossils indicate that after the Nantuo ice age, macroscopic muiticellular organisms gradually increased in abundance and diversity. Simple, discoidal carbonaceous compressions such as chuarids are present in the initial macrofossil assemblage of the Doushantuo Stage. This assemblage was eventually replaceded by the more diverse Miaohe macrofossils, including unambiguously branching forms, in the uppermost Doushantuo Formation. The new discovery of carbonaceous compression macrofossils from the Doushantuo Formation in the Yangtze Gorges area provides new evidence for the correlation of late Neoprotero-zoic successions in southern China.