Abstract: B block is located in the eastern part of the Oued Mya Basin in Algeria,and may have been subjected to several phases of uplift and denudation from the Ordovician onwards.The Caledonian orogeny led to the partial absence of the Silurian and Devonian strata,while the uplift of the basement during the Hercynian was responsible for the complete omission of the Carboniferous and Permian strata.The braided stream deposits were developed during the early Late Triassic.There are gradations from the early Late Triassic braided stream deposits to the middle Late Triassic meandering stream deposits and late Late Triassic saline lake deposits.In addition,the intense volcanic eruption during the early and middle Late Triassic also brought about tremendous pyroclastic rocks in the study area.According to the high-resolution isochronous stratigraphic correlation,the authors arrived at the construction of the Late Triassic stratigraphic framework and laid the foundation for the construction of the palaeogeographic framework and delineation of the targets for further hydrocarbon exploration.