关于深水环境下内波、内潮汐沉积分类的探讨

Proposed Classification of Internal-wave and Internal-tide Deposits in Deep-water Environment

深水环境下内波、内潮汐沉积从在地层记录中被发现已过去20年,在这20多年里虽然积累了不少资料,但至今未对内波、内潮汐沉积进行细分。本文以地层记录中已发现的内波、内潮汐沉积为基础,结合内波、内潮汐的破碎过程和海洋物理学中内波的研究现状,对深水内波、内潮汐沉积的分类进行了探索。将其分为3个层次下的9种类型,分别为:正压内潮汐沉积、斜压内潮汐沉积、正压短周期内波沉积、斜压短周期内波沉积、等深流叠加内波沉积、低密度浊流叠加内波沉积、长周期内波叠加沉积、驻波沉积和其他内波叠加沉积。地层记录中已发现的内波、内潮汐沉积分别归为:正压内潮汐沉积、正压短周期内波沉积和长周期内波叠加沉积3类,其余类型尚未被发现。这样的分类较合理地解释了为什么在现代海洋中内波、内潮汐无处不在,但地层记录中的内波、内潮汐沉积却少得可怜的现象,同时将内波、内潮汐沉积研究和海洋物理学中对内波的研究结合起来,并能将内波、内潮汐沉积研究置于更为广阔的研究背景之中,使之可以和大洋突发事件、天文旋回及大洋环流等联系起来。

There are no efforts have been made for the classification of internal-wave and internal-tide deposits for more than twenty years since they were discovered in the geological records. Here we try to propose a classification of internal-wave and internal-tide deposits based on the types which were already discovered in sedimentary rocks as well as the breaking processes of internal waves and its development research in physical oceanography. There are nine types through three orders, which include barotropie internal-tide deposits, baroclinic internal-tide deposits, barotropic short-period internal-wave deposits, baroclinic short-period internal- wave deposits, contour currents interaction internal-wave deposits, low-density turbidity currents interaction internal-wave deposits, long-period internal wave interaction deposits, standing internal-wave deposits and other internal wave interaction deposits. The discovering internal-wave and internal-tide deposits in geological records are attributed into barotropic internal-tide deposits, barotropic short-period internal-wave deposits and long-period internal wave interaction deposits. And the other six types are still unrecognized. The classification proposed here perhaps give a reason for the phenomena that internal waves occur nearly ubiquitously in oceans yet their sedimentary records remain largely unrecognized. Furthermore, this classification is help for connecting the deposits of internal-waves not only with its research in physical oceanography, but also with the oceanic unexpected events, ocean circulation and astronomical period in geological history.