The petrographic characteristics and the upper stratigraphic boundary of limestone late permian in the geological section in South – Eastern region, Vietnam

In the South – Eastern region, Vietnam, the stratigraphic boundary of Late Permian - Early Triassic has long been considered as an unconformity boundary between Ta Vat formation (Late Permian) and Song Saigon formation (Early Triassic). Recent studies on the petrographic and geological structure of this section suggested that it may be a conformable stratigraphic boundary, where there is the transition from limestone series such as grainstone, packstone, wackstone of Ta Vat formation to the sedimentary rocks such as claystone, and marl. This characteristic was closey related to the geological structure of Song Saigon.