In Upper Triassic Brigadier Formation, there developed delta sandstone and mudstone in the southeast of Northern Carnarvon Basin, whereas developed carbonate rock in the northwest of the basin. According to some proofs of source input in the southeastern part of the basin, there developed siliciclastic sediments of delta facies near the provenance,and developed reef-shoal sediments and slump sediments away from the provenance. It is suggested that the mixed sedimentation in the Brigadier Formation is a typical facies mixing with carbonate rocks on the early fluvial sandstones,mainly due to the cessation of debris input and the reduction of hydrodynamic forces.