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对华南地区贵州罗甸大文剖面早三叠世早期的凝块石进行了系统的沉积学描述,区分出斑状、层状、枝状和网状4种中型构造。凝块石所具有的沉积构造特征和岩石学统计数据表明其形成于潮下带沉积环境,其中,斑状和层状中型构造的凝块石形成于能量较低的深潮下带,而枝状和网状中型构造的凝块石形成于能量较高的浅潮下带。18个向上变浅的沉积旋回显示Hindeodus parvus带内部海平面逐渐降低;Isarcicellastaeschei带和I.isarcica带早期,海平面降到最低,之后海平面开始升高。通过与其他地区二叠–三叠系界线剖面的海平面变化情况对比发现,全球普遍存在二叠–三叠纪之交的海平面下降,而大文剖面早三叠世早期的H.parvus带、I.staeschei带和I.isarcica带的海平面变化情况在古特提斯洋范围内可以广泛对比,可能主要受到全球海平面变化的影响。
Sediments of the Early Triassic in the Dawen Section of Luodian, Luodian, South China, were systematically described by sedimentology, and four kinds of midstructures were distinguished, such as macular, layered, dendritic and reticular. The sedimentary structural features and petrologic statistics of the clinker stone indicate that it is formed in the subtidal sedimentary environment, in which the macular-shaped and layered medium-sized clinker stones formed in the lower energy zone and the dendritic And the mesophase structure of the coagulum formed in the higher energy of shallow tidal band. Eighteen upward-shifting sedimentary cycles show that the sea level of Hindeodus parvus decreases gradually, while the Isarcicellastaeschei and I.isarcica belts decrease to a minimum and the sea level begins to increase afterwards. Compared with the sea level changes of the Permian-Triassic boundary line in other areas, it is found that there is a general decline in the sea level at the turn of the Permian-Triassic, while the H. parvus zone of the Early Triassic in the Dawen section The sea level variability in the I. Estaïche band and the I. ossarc band can be widely compared within the Gêtti oceanic range and may be mainly influenced by global sea level changes.