Abstract: The establishment of turbidity deposits theory is of an epochal meaning, which is over half a century and a great of key progress has been achieved. In this paper, the turbidity current's definition and several related concepts are firstly discussed, meanwhile, the history and the actuality on turbidity current are also summarized, in which, the identiclation signs and the sedimentary sequence as the most important content are introduced. Then, an idea is pointed out that the further key study should be focused on the terrigenous lacus and its mine-containing probability.