南海北部湾海洋工程地质特征

CHARACTERISTICS OF MARINE ENGINEERING GEOLOGY IN THE BEIBU GULF OF THE SOUTH CHINA SEA

根据地球物理、声学探测及海底取样等实测资料详细分析 ,发现北部湾油气勘探开发区具有近岸、水浅等优越自然条件以及复杂的海洋工程地质特征。海底地形地貌较为复杂 ,存在潮流沙脊与潮沟、海底沙波、埋藏古河道、浅层气、埋藏古陡坡、滑塌断层及可能的砂土液化层等潜在灾害地质因素 ,对海上构筑物存在直接或潜在的危险性。尤其在东部 ,海底坎坷不平 ,活动性的潮流沙脊、侵蚀沟槽、海底沙波及浅层气等很发育 ,是海底工程建设的危险区 。

On the basis of geophysical prospectings,acoustic survey and sea floor sampling,the oil and gas exploration areas in the Beibu Gulf are found to have excellent natural conditions such as short distances from the shore and shallow water depth,but the sea floor topographical and geomorphological features are very complex.There are many geological hazard factors such as tidal sand ridge,tidal channel,submarine sand wave,buried river channel,sliding, fault and possible liquefaction of sand,which will give potential or direct dangers to marine engineering constructions.Especially in the east of the study area,the sea floor is very rough,and active tidal sand ridges,erosion grooves,submarine sand waves and shallow gas are well developed.We should pay attention to the dangerous factors when conducting submarine engineering project.