Continuous hydrocarbon accumulation over a large area is a distinguishing characteristic of unconventional shale stratum hydrocarbons, and has great petroleum resource potential. The geological connotation of shale stratum oil and gas is put forward, that is, continuous distribution of oil and gas resources is generated, detained or gathered close to the tight reservoirs within or adjacent to the hydrocarbon-generating stratum, and the industrial exploitation can be realized by using new technologies, including two resource types of source-reservoir integration and source-reservoir adjacency. Examples of unconventional hydrocarbon accumulations are Mesozoic Triassic shale oil province and Upper Paleozoic Carboniferous-Permian shale gas province in Ordos Basin. Tight oil and gas, and shale oil and gas in Ordos Basin are mainly distributed in source-kitchen or near-source reservoirs in large areas, which are typically characterized by hydrocarbon-bearing, tight reservoir, low formation pressure, and low resource abundance. Stable tectonic setting, widespread matured source rocks and large-scale superimposed tight reservoirs are favorable to hydrocarbon accumulation. “Sweet area(section)” of tight oil and gas is mainly controlled by the hydrocarbon-generation center and massive sandbodies. “Sweet area(section)” of shale oil and gas is mainly controlled by the organic-rich shale scale, thermal evolution and natural fractures. Research on such resources will be at the forefront of the future development of petroleum geology.