Abstract: The palaeotemperature evolution of Bayindulan depresion has been recovered with the method of vitrinite reflectance. Research results indicate that the geothermal field of Jurassic was different from that of Cretaceous. Palaeogeothermal gradient in Late Jurassic was higher than that in Cretaceous. Palaeogeothermal gradient in Early Cretaceous was between 4.80℃/100m to 5.50℃/100m. The depression has uplifted as a whole and geothermal gradient has decreased since Late Cretaceous. Evolution characteristics of lower Cretaceous source rock were mainly controlled by palaeotemperature. Period of main oil generation was during the deposition of groupes from the second member of tengger group to the saihan group.

Key words: Erlian Basin, Bayindulan Deperession, palaeotemperature, palaeogeothermal gradient, period of oil generation

摘要： 应用镜质体反射率法恢复了巴音都兰凹陷的古地温演化史,研究结果表明巴音都兰凹陷侏罗纪与白垩纪具有不同的地温场特征,晚侏罗世古地温梯度高于早白垩世地温梯度,早白垩世地温梯度可达4.80～5.12℃/100m,晚白垩世以来凹陷整体抬升,地温梯度降低。下白垩统烃源岩热演化程度主要受古地温控制,主生油期在腾二段及赛汉组沉积时期。

关键词: 二连盆地, 巴音都兰凹陷, 古地温, 古地温梯度, 生油期