Abstract: Abstract：After 1309 days of hard work, the Chinese Continental Scientific Drilling (CCSD) project drilled a total depth of 5118.20 m and reached its target depth by January 23th, 2005. The well completion is a new landmark in the development of China′s drilling technology. A comprehensive on-going study is being carried out and great advances have been made in the following aspects：precise dating of deep subduction of voluminous continental materials, UHP deep subduction and exhumation, setting of formation of protoliths of UHP rocks, upper mantle rheology, discovery of special, new mantle minerals and discovery of subsurface fluid anomalies and subsurface microorganisms.