【摘要】 <正> 现代海洋环境的稳定程度,取决于地壳内营力和外营力相互作用的结果。所谓内营力是指地壳升降、断裂活动、地震、火山、热流以及大地构造性质等对海洋环境的控制和影响;外营力是指潮汐、河流、风暴、浊流、沿岸流、海平面升降变化、生物作用以及沉积物的特性对海洋环境的影响。在构造相对稳定的海域,海洋环境的稳定程度主要取决于外营力的影响;在构造活动强烈的海城,则主要决定于内营力的作用。这样的海域一旦发生强烈地壳运动及伴随而来的强震、海啸或火山喷发,往往瞬间就会给海洋工程带来惨重的灾难。因此,许多沿岸国家都十分重视研究影响海洋环境的新构造运动,把它作为海洋工程区域稳定性评价的一项基础工作。更多还原

【Abstract】 This paper presents a brief discussion on the stability of the marine environments of the northern South China Sea in a few aspects.They are: 1) the geotectonic environment;2) active faultS;3) elevation and subsidence of fault blocks;4) seabed earthquakes and tsunamis;5) volcanoes and heat flow; 6) eboulement, landslip and turbidity current forming along the actively structural zone.According to the analyses of the above-mentioned features, the geotectonic character of the South China Sea was a new type of continental marginal sea Diwa,the northern area of the South China Sea was between an active continental margin and a passive continental margin. Hence,the neotectonic environment of the South China Sea is relatively stable and is suitable for developing seabed oil.The Zhujiang Mouth Basin, Beibu Gulf Basin and Yinggehai Basin are all in the areas where earthquake action is relatively calm,there are no records of Ms≥6 in its history. So long as we keep away from the active fault boundary of differential elevation-subsidence,no significantly harmful effects will exert on marine engineering projects.更多还原