Abstract:

The piedmont zone includes fold-thrust belt and foreland basin adjacent to the orogen. According to the formation mechanism classification of foreland basin，piedmont zones can be divided into three types，i. e. retro-arc foreland piedmont zone，peripheral foreland piedmont zone and rejuvenated foreland piedmont zone. Based on the superimposed basin classification，piedmontzones can be divided into positive inversion piedmont zone and successor foreland piedmont zone. Rejuvenated foreland piedmont zone and successor foreland piedmont zone are only found in the middle and western China. Some principles of hydrocarbon accumulation in piedmont zone have been summarized. Pre-foreland shale is source rock，foreland sandstone and pre-foreland carbonate rock are good reservoirs，and mudstone，gypsum salt and salt rock are cap rocks. Fault is the main channel of hydrocarbon migration. Structural trap is the main type in the fold-thrust belt，while structural-stratigraphic trap is dominated in the foreland basin.

Key words: piedmont zone, structural deformation, hydrocarbon accumulation, western Canada piedmont zone