湖盆滩坝沉积研究进展

 介绍了滩坝的定义，综述了湖盆滩坝研究的相关成果。滩坝可根据其沉积物、发育位置以及对与潮汐作用响应等进行分类。基于沉积物，滩坝分为碳酸盐岩滩坝和碎屑岩滩坝；基于发育位置，滩坝分为近岸滩坝和远岸滩坝等；基于对潮汐作用响应，滩坝分为小潮差滩坝、中潮差滩坝和大潮差滩坝等。针对滩坝砂体沉积特征提出滩坝的沉积模式，并可进一步对其内部微相进行划分。滩坝发育的控制要素为古地貌、水动力条件、沉积旋回、物源以及古水深、古气候等，古地貌的控制体现在岸线形态和局部地形起伏；水动力条件的控制体现在不同强度的波浪作用；沉积旋回的控制体现在基准面的升降和旋回；物源的富集及贫乏对滩坝的形成类型起到决定性作用；古水深、古气候则影响滩坝的发育与否。

Research progress of lacustrine beach-bars

Starting from the definition of the beach bar, this paper comprehensively reviews the latest progress of the beach bar research. According to the deposit types, the locations and the responses to the tidal action, the beach bars can be classified. According to the deposit types, the beach-bars can be divided into the carbonate beach-bars and the detrital beach-bars. According to the development locations, the beach-bars can be divided into the near shore beach-bars and the off shore beach-bars. According to the responses to the tidal actions, the beach-bars can be divided into the low tidal beach-bars, the middle tidal beach-bars and the high tidal beach-bars. In this paper, in view of the sedimentary characteristics of China's lacustrine beach bars, the sedimentary patterns of the beach bars are summarized and their internal microfacies are further divided. The development of the beach bars is controlled by the paleogeomorphology, the hydrodynamic conditions, the material source, the sedimentary cycle, etc. The controlling function of the paleogeomorphology is reflected in the configuration of the shoreline and the local topographic uplifts. The hydrodynamic condition controls the water flow in the development of the beach-bar, which is reflected in the wave actions of different strengths. The material source is the material foundation of the beach-bars and the beach-bars are better developed with abundant materials. The controlling effects of the sedimentary cycle on the beach bar is reflected in two aspects, the rise and fall of the datum level and its cycle. The paleo water depth and the paleoclimate control the development of the beach-bars, especially, the carbonate beach-bars.