Shallow gas hydrates had already been retrieved by gravity corer, busyness fishing net, and submersible machine on the sea floor and in the sediment near to the sea floor.

• 摘要使用重力取样器、渔网、深潜器等手段已经在海底及以下浅表层区域采获天然气水合物样品。但关于浅表层水合物的发育机制、分布规律及与海底地形的关系等问题还缺乏基本认识。