The International Union of Geological Sciences (IUGS) has recognised Ha Long Bay - Cat Ba Archipelago in the northern province of Quang Ninh and neighbouring Hai Phong City as a world geological heritage site, Associate Professor Dr Tran Tan Van, former Director of the Vietnam Institute of Geosciences and Mineral Resources under the Ministry of Natural Resources and Environment (MoNRE), said on August 25. Ha Long Bay - Cat Ba Archipelago includes all stages of the marine submergence of tropical karst as well as three main types of caves - ancient marine frog-jaw caves, ancient karst caves and frog-jaw caves. The Ha Long Bay represents the later stages of the marine subduction while the Cat Ba Archipelago adds important geological values to the heritage through its patterns of the terrestrial and intertidal stages. Source: Vietnam News Agency