渤海湾盆地东濮凹陷古生界煤成烃特征模拟实验研究

通过渤海湾盆地东濮凹陷石炭—二叠系煤系地层实际地质条件下煤的半开放体系加水热模拟实验研究，刻画了该区煤岩不同温压介质条件下生排烃特征及潜力。研究表明:（1）东濮凹陷石炭—二叠系煤具有极高的生烃潜力，最高产烃量达254 mg/g，其中气态烃总产率220 mL/g，液态烃最高产率为145.8 mg/g；（2）煤成油的演化呈峰形尖锐的单峰特征，生油高峰在325 ℃（R_o＝1.08%），生成的液态烃类近40%排出煤体；（3）煤成气的演化呈多阶段性逐渐增大的特征，其中325~450 ℃和500~550 ℃2个区间气态烃类快速增加，前者主要缘于液态烃的大量裂解，后者是煤芳香结构进一步稠合生烃演化产生；（4）东濮凹陷石炭—二叠系煤既生油又生气，其煤成油潜力与吐哈盆地侏罗系煤相当，煤成气潜力与鄂尔多斯石炭—二叠系煤相当。 

Simulation of hydrocarbon generation of the Paleozoic coals in the Dongpu Sag,Bohai Bay Basin

The hydrocarbon generation and expulsion characteristics under different temperatures and pressures and the hydrocarbon potential of coals were studied based on the thermal simulation with water in a half-open system of coals using the geological conditions of the Carboniferous-Permian coals in the Dongpu Sag, Bohai Bay Basin. The results indicate that: (1) The Carboniferous-Permian coals in the Dongpu Sag show a very high hydrocarbon generation potential. The yield of hydrocarbon generated can reach 254 mg/g, among which the gaseous products account for 220 mL/g, and the liquid part about 145.8 mg/g. (2) The yield of thermal cracking oil from coal shows a single peak, which appears at 325 ℃ (R_o=1.08%). Almost 40% of the liquid hydrocarbon was expelled from coal. (3) The hydrocarbon generation of coal followed an increasing tendency in several stages. The intervals 325-400 ℃ and 500-550 ℃ are the stages when gaseous hydrocarbon shows a rapid increase. The former increase should be a result of thermal cracking of liquid hydrocarbon, while the latter maybe caused by the condensation of aromatic hydrocarbon. (4) The Carboniferous-Permian coals in the Dongpu Sag yielded both oil and gas, with an oil generation potential appro-ximately equal to that of the Jurassic coals in the Turpan-Harmi Basin, and a gas generation potential matching the Carboniferous-Permian coals in the Ordos Basin.