【摘要】 近年来的地质与地球物理调查发现,在大陆坡第四系中发育有大规模块体搬运体系(现今的块体搬运体系也称海底滑坡)。块体搬运体系是深水常见的一种沉积物搬运机制,主要包括滑动、滑塌和碎屑流等重力流过程及其沉积物。南海陆坡白云块体搬运体系面积逾10000km2,可划分为3个结构单元,即头部拉张区、体部滑移-挤压区和趾部挤压区。在地震剖面中,发育多种构造:正断层、杂乱反射、逆冲断层、挤压脊和褶皱等。块体搬运体系严重威胁深水设施安全,并可能诱发海啸,是海洋地质灾害之一。同时,块体搬运体系与海洋油气及天然气水合物关系密切,物源决定块体搬运体系的物性,泥质物源的块体搬运体系通常作为良好的油气盖层,砂质物源形成的块体搬运体系可以成为储层。更多还原

【Abstract】 A lot of large mass transport depositions (MTDs) have been discovered in the Quaternary strata according to recent geological and geophysical investigation results. MTDs are very popular sedimentary systems in the continental slope,which include slides,slumps and debris flows. Total area of Baiyun MTDs in Quaternary strata of the northern South China Sea is over 10 000 km2. Architecture of MTDs in Quaternary strata is divided into headwall extensional domain,translational-compressional domain and toe domain compressional area. On the seismic profiles,MTDs show many structures such as: normal fault,chaotic reflection,thrust fault,pressure ridge and fold. MTDs are one of the important geological hazards,do harm to deepwater equipments and induce tsunamis. At the same time,MTDs have close relationship with formation of deepwater hydrocarbon and gas hydrate. MTDs are usually good seals in deepwater because of its lower porosity and permeability,and could be reservoirs if the slumps are originally good sandstones.更多还原