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大贵州滩是右江盆地内的一个三叠纪孤立碳酸盐岩台地。其早三叠世滨潮坪５级小旋回（厚０．５～８ｍ）是由潮下泥粒灰岩和潮间条纹岩及蓝藻细菌粘结岩等组成的。小旋回组合规律为：小旋回按４∶１（个别为３∶１）的比例组成小旋回束，后者又按３∶１的比例组成小旋回组。各小旋回束、小旋回组和海侵—海退旋回下部的小旋回均厚度较大，潮下沉积相对发育；上部的均厚度较小，潮间沉积相对发育。这种特征可作为滨潮坪沉积序列中３、４级旋回（层序）内地层的退积和进积堆积型式的识别标志。大贵州滩早三叠世滨潮坪小旋回同美国科迪勒拉、阿巴拉契亚晚寒武世碳酸盐岩滨潮坪米级旋回的相组合与堆积型式特点非常相似。为了便于研究高频旋回堆积型式和在地表暴露不整合不发育的地层序列内划分３级层序，本文提出３～５级海侵—海退旋回及层序的划分方案：５级为小旋回、复合小旋回，相应层序为小层序、复合小层序；４级为小旋回束、小旋回组，相应层序为小层序束、小层序组；３级为海侵—海退旋回、复合海侵—海退旋回，相应层序为海侵—海退层序、复合海侵—海退层序。大贵州滩早三叠世海侵—海退层序２总时限为２百万年，含５８个小旋回、１５个小旋回束、５个小旋回组，其小旋回和小旋回组的平均年龄分别?
Big Guizhou Beach is a Triassic isolated carbonate platform within the Youjiang Basin. Its Early Triassic Binhai Ping 5-level small cycle (thickness 0.5 ~ 8m) is composed of tidal mudstone and intertidal striated rock and cyanobacteria bacteria binding rock. Small cyclical combination of rules: small gyration by 4: 1 (individually 3: 1) ratio composed of small cyclone beam, which in turn according to the ratio of 3: 1 small cyclical group. Small Cyclone, Small Cyclotary, and Transgression-Cyclone receding lower Cyclone have thicker thickness and relatively developed subtidal sediments. The upper average thickness is relatively small, and the intertidal sediments are relatively developed. This feature can be used as a marker for the deposal and accretion accumulation patterns of the formations in the 3rd and 4th cycles (sequence) of the Binchenping sedimentary sequence. The characteristics of the assemblage and accumulation pattern of the Early Triassic Bingshadaping small cycle in the coast of the Big Guizhou Island are similar to those of the Late Cambrian carbonate tidal flat tidal flat in the American Cordillera and the Appalachia. In order to facilitate the study of the high frequency gyration types and the classification of sequence stratigraphy within stratigraphic sequence of undeveloped surface unconformity, this paper proposes a classification scheme of transgressive-regressive cycles of 3 to 5 levels and sequence: , The small cycle of complex, the corresponding sequence of small sequences, complex small sequence; 4 small swirling beam, small cycle group, the corresponding sequence of small sequence stratigraphic sequence, small sequence; Level 3 transgression - sea Backstroke, complex transgression - regression back to sea, the corresponding sequence of transgression - regressive sequence, complex transgression - regressive sequence. The early Triassic transgression-descending sequence 2 in Guantong Bay has a total time limit of 2 million years, including 58 small cycles, 15 small cycles and 5 small cycles. The average of the small cycles and small cycles Age difference?