Late Paleoproterozoic to early Mesoproterozoic Dongchuan Group in Yunnan, SW China: Implications for tectonic evolution of the Yangtze Block

The Dongchuan Group including the Yinmin, Luoxue, Etouchang, and Luzhijiang Formations from the base upward has extensive outcrops in the western Yangtze Block. It was previously thought to be the lower part of the late Mesoproterozoic to early Neoproterozoic Kunyang Group, but there was a lack of precise age determination. The whole sequence is more than 4 km in thickness and consists of conglomerate, sandstone, slate, dolostone, carbonaceous...