Closure of oceanic basins, uplift of mountain ranges, and accumulation of thick terrigenous clastic sediments in the foreland basin resulted from collision between continental margins. Relatively complete geological records can be preserved in the foreland areas of orogenic belt, which were once a passive continental margin and located at relatively low structural positions. The middle and lower reaches of the Yangtze River are the foreland tectonic belt of the Dabieshan orogen. Through investigation and analyses of sedimentary settings especially the provenience of sediments, the Sinian-Jurassic sedimentary strata exposed in the study area have been recognized as Sinian-Lower Triassic passive continental marginal sequences and the Middle Triassic-Middle Jurassic foreland basin sequences. And then, it is inferred that the collisional orogeny in the Dabieshan orogen took place in the Middle Triassic. The spatial distribution of the Lower Triassic passive continental marginal sequence and foreland basin sequences demonstrates the collisional pattern of the Sino-Korean and Yangtze blocks, indicating that the collision was basically simultaneous from east to west in the middle-lower reaches of the Yangtze River.