Sedimentological environment and diagenetic metallogenesis of Dongchuan-type stratiform copper deposits in western Sichuan and Yunnan

Lagoon behind stromatolite-reefs and bathyal areas in front of the reefs are the original basins where copper-bearing water was accumulated. The corresponding rock facies are the rear-reef bay syngenetic dolomite and the pro-reef black shale and dolomite respectively. Stratiform copper deposits were formed during diagnesis, being genetically connected with the stromatolite reef. No direct genetic relationship has been established between copper mineralization and volcanic tuffs.