Hydrocarbon Accumulation in Meso-Cenozoic Lacustrine Remnant Petroliferous Depressions and Basins, Southeastern China: Chapter 20

摘要: More than 140 small lacustrine Meso-Cenozoic remnant petroliferous depressions and basins are distributed along deep fault zones in southeastern China. Some contain abundant oil gas reserves high-yield traps, although areal extent of this type basin is only 800-1000 km2. Among the structural lithologic characteristics hydrocarbon accumulations these (1) distribution zones, (2) widely distributed, thick source rocks, (3) well developed sand bodies, (4) high geothermal gradient, (5) multiple-trap styles. China thick, deep-water shale, primary rocks for region's accumulations. These dark, organic-rich, fine-grained strata were deposited deeper parts lake basins. Consequently, principal have been preserved over much their original extent, uplift erosion following shale deposition resulted destruction depression margins. Most structures occur as half-grabens resulting from successive development faults one side basin; however, some also may appear full grabens. Well consist three characteristic elements--(1) step-faulted belt on steep flank, central, low buried-hill belt, monoclinal slope gentle flank. Examples types include Damintun, Lanpu, Sulu depressions, Baishe Sanshui Poorly a central trough, Biyang, Changwei, Qianjiang, Yuanjiang , Maoming basin.