Palaeotopography and its Constraint on the Development of Depositional Facies Period of Early Cretaceous in Tabei

Based on well logging and seismic calibration, the approximate paleo-level method was used to recreate the palaeotopography before deposition of Yageliemu stage, and then the study area was subdivided into three geomorphic units, high uplift, slope and depression. The braided river delta, oxidized shallow water delta, bank-bars as well as lacustrine sedimentary systems were identified through cores, mineralogy and logging data. Via debris composition, heavy mineral, seismic property studies, the lateral distribution of sedimentary systems were identified. This research revealed that the source to sink systems in study area are obviously controlled by topography, and there are two source districts, uplift and south-east, and braided river delta sediments developed in both the south and north sides of the eroded paleo-unplift. The southeastern source lack sediments supply, therefore only small oxidized shallow delta developed.