Occurrence and Geological Significance of Stromatolites from the Precambrian Strata in the Socheong Island, Incheon, Korea

Stromatolites are firstly described from the limestones of the Pricambrian Sangwon System in the Socheong Island, Incheon, Korea. They are described as Baicalia f.1, B. f.2, B. f.3., Inzeria f., Jinshanzhaiella pulchellusa, and Linella cf. simica. Stromatolites from the Sangwon System in the Socheong Island are similar to stromatolite assemblage VI and VII representing the Precambrian Qingbaikou System in China. Based on the stromatolites and lithology, the stromatolite - bearing strata in the Scheong Island are possibly correlated with the Late Proterozoic Mukchon and Myoraksan Series, upper part of the Sangwon System which is mostly distributed in North Korea. On the basis of the morphology of stromatolites characterized by mainly vertically-stacked hemispherical forms with mud cracks and rain prints, the strata in the Socheong Island seem to be deposited in the warm and shallow tidal flat environment. This is the first report on the occurrence and description of the Precambrian stromatolites which are the oldest fossils ever discovered in Korea.