The Origin of Pb - Zn Deposits in the Northern Kuandian Area, Liaoning Province

Carbonates and clastic rocks are well developed in the second - order basins of an Paleoproterozoic aulacogen in the northern Kuandian area, Liaoning Province. The carbonates consist of two parts, the upper and the lower carbonate formations. The clastic rocks occured between the two formations. Two Pb- Zn ore belts exist in both of upper and lower carbonate formations and are called B and A - belt respectively. Several tens of Pb - Zn ore bodies are found in A - belt. Some Pb - Zn ore bodies are apparent in vertical zoning in a sequence of Fe - Zn - Pb - Ba from the lower to the upper. Geological and geochemical researches show that the ore components in the A- belt was exhalated from the liquid source bed deeply and was precipitated in a closed second - order basins. While those in the B - belt was derived from the upper crust and was deposited in a normal oceanic enviornment. The second - order basins in Liaodong - Ji' nan - North Korean Peninsular aulacogen at the margin of the Archean craton are promising sites for looking for the deposits formed by exhalation of the liquid source bed deeply under crust.