HQ-13 Line is the first comprehensive geophysical-geological sectionstretched deeply to the bottom of the lithosphere in the Lower Yangzi Reaches.The section

over 500km long

starts form Lingbi of Anhui Province in then orthwest to Fengxian of Shanghai in the southeast. Gravity survey

aeromag-netic survey

crustal seismic sounding

crustal seismic reflection

geo-electromagnetic sounding

absorbed hydrocarbon

soil mercury measurement and ground geological survey have been carried out on the section. They have revealed the structural features of the crust and mantle of this area which have"eight sides"

"seven layers" in vertical and "four blocks" in horizontal.Twelve major geological achievements have been obtained. Some of the achieve-ments belong to basic geological theory

e. g.

multiple glides. multi-layerbalanced adjustment

the evolution sequence of depression-uplift exchange instructural layers in vertical: confirming the Moho to be transition layer ofseveral thousand meters thick

the multicontrol of deep-seated geologicalfactors over structural evolution of basins

etc…… Some are great regionalgeological questions

including the confirmation of both deeper and shal-olwer metamorphic crystal basements

the discovery of the Shuanggou nappe beltas the boundary between the North China Platform and the Yangzi Para-platform. Some are related directly to hydrocarbon exploration

such as the thickness

buried depth and internal structural features of Paleozoic and Me-sozoic marine sediments

the heterogeneity of geothermal fields in verticaland horizontal directions etc..