Abstract: Along with the development of seismic stratigraphy，the sequence stratigraphy was founded in the late 1970's and has become one of the branches of interest in geology today.This paper briefly introduces the significance of sequence stratigraphy and the origin of clas-
sical sequence stratigraphica( theory，and studies the particularity of sequence stratigraphy of this area under the guidance of the sequence stratigraphical theory，and in combination with
the characteristics of Early Silurian epicontinental sea ramp at NW margin of Yangtze Plat-form. It further demonstrates that the sequence stratigraphical theory dose not completely
apply to the sedimentary combination in the epicontinental sea ramp environment and needsto be supplemented and rectfied. This paper also discusses the condensed bed and its oil-gas
generating significance.

Key words: Sequence stratigraphy, Sedimentary environment, Sequence character-isties, NW margin of Yangtze Platform, Early Silurian