In article from Russian military magazine Chinese mines as the possible reason of destruction Cheonan are mentioned. Whether there are data on the Chinese complex mines?
http://www.sinodefenceforum.com/wor...rean-corvette-cheonan-27-4978.html#post121964
“Perhaps, a mine is guilty in destruction of the ship? It was the main and most logical version during first moment. The set of various mines has been laid in this area within war 1950-1953. Mine-laying were rather probable the next years by both sides, including secret mining.
Version of a bottom mine disappears because explosion took place in 30 meters above sea bottom. A anchor mine is improbable because it cannot keep constant depth because of strong currents in this area. Currents achieve 6 knots and change directions.
Theoretically there is an opportunity of application of more complex device - an floating-up mine or a jet-mine or even a mine-torpedo. In the latter case, the torpedo could be in the mine container at sea bottom and to start therefrom after detection of corvette's noise. ASW mine- torpedoes are well-known: American Mk 60 Captor and Russian PMR and PMK. In case of Cheonan, ASuW emerging mines KRM and RM, created in the USSR in 1957-1965, and also their Chinese analogues are most interesting. They could lie down on depths from 40 meters, carried a charge of 200-300 kg and blew up on depth about 10 m during emersion. However, the heavy hydrology should prevent work of complex systems. Besides torpedo container or anchor of emerging mine should remain at the bottom.”