Characteristics Of Acoustic Reflection And Geological Significance Of Liaodong Shoal’S Shallow Strata

Liaodong Shoal which located in the south of the Liaodong Bay，and north ofLao Tieshan Strait is one of the typical tidal sand ridge in china.In recent years，thereflection characteristics of the whole Bohai Sea’s shallow profiles have been moreanalysis and research，however，the studies focused on the relationship between theseismic sequence and geologic disaster are few.In this paper，we use the theory of seismic stratigraphy and sequence stratigraphyto interpretation the shallow profiles.According to the previous borehole data and theresults of the survey we can divid the study area into five acoustic reflectionstratigraphic units and subunits.confirming the SU₁，U₃，U₅stratigraphic reflector unitcorresponding to oxygen isotope of1，3，5marine deposits.We also recognize the U₄²acoustic reflection stratigraphic sub-unit in the study area corresponds to the BohaiSea transgression， worthing of independent draw.Each sedimentary sequencerepresents a large-scale transgression-regression.Since the Quaternary Bohai Sea hasexperienced four major transgression-regression，which become Identification markin the seismic profile.According to the principle of seismic stratigraphy，we study theamplitude，phase，frequency，continuity，reflectance character of the seismic waveto identify a variety of buried ancient landforms，such as buried ancient rivertidal sandridges，shallow gas，fault，igneous.The buried ancient landforms have potential so thestudying for buried ancient landforms has very important significance to the marineengineering，and is very important to restore the regional paleo environment.In recentyears，as the continuous development of the geological survey and research of marinedisasters，the studies for buried ancient landforms have been paied enough attention.