Curie-point pyrolysis-GC/MS experiments were conducted on three oil shales derived from different mines in Huadian Basin to characterize the fast pyrolysis features and the oil product distribution regularities. Pyrolysis experiments at two different Curie temperatures of 485 degrees C and 590 degrees C were carried out on all the three oil shales respectively to study the influence of temperature on the pyrolysis shale oils. The results showed that in the sedimentation process of kerogen, part of the aliphatic chains are transferred into aromatic rings leading to the decrease of aliphatics and increase of aromatics. Also, part of the oxygen-containing functional groups are removed leading to the decrease of oxygen-containing organic compound proportion in the shale oil. With the increase of temperature from 485 degrees C to 590 degrees C, large amounts of n-alkanes were transferred into cycloalkanes and alkenes due to the secondary cracking reactions. Oxygen-containing organic compounds including phenols, alcohols, esters, and ketones existed in the pyrolysis oil products of all samples. Contents of alcohols increased with temperature while that of esters and ketones decreased obviously. (c) 2014 Elsevier B.V. All rights reserved.