1. Guangzhou Marine Geological Survey��Guangzhou 510075��China; 2. College of Earth Sciences��Jilin University��Changchun 130061��China

The North Yellow Sea is located amongst the sulu orogenic belt��linjin river orogenic belt and jiao- liao uplift�� The basin is divided into 6 secondary structure units which contain one depressed structure��two uplifts structure and three sags�� Formations include middle Jurassic��upper Jurassic and lower cretaceous in the eastern depression�� The sedimentary sequences were formed in continental environment�� The basin filling succession can be classified into 8 third order sequences��and 2 of them are upward- fining sedimentary succession in extension tecton- ic background��in middle Jurassic�� There are 2 third order sequences in upper Jurassic��which are upward- fining sedimentary succession in extension- inversion tectonic background�� Compressional structure facilitated strata erosion in the late Jurassic�� There are 4 third order sequences in lower cretaceous��controlled by compressional structure�� The strata was eroded seriously and partial sequences missing�� Logging data analysis of the Well B32 and Well B21 draw a conclusion that Th/U ratio of these 2 wells could be compared effectively��and the basin evolution of exten- sion structure -compressional structure were proved in terms of the paleo- water- depth and the sea level change�� The structural evolution section analysis considered that the sequence development and distribution were affected by tec- tonic activity��and the basin evolution characteristics of transform structure- extensional structure were proved��