INVESTIGATION ON SECONDARY MIGRATION OF OILS IN CENTRAL TARIM, TARIM BASIN USING PYRROLIC NITROGEN COMPOUNDS
Liu Luofu; Kang Yongshang (The University of Petroleum, Beijing 102200)
Carbazole compounds were fractionated and detected in oils from the Central Tarim district, Tarim Basin, and these nitrogen compounds were utilized for research work of oil migration successfully. A vast amount of alkylcarbazoles was discovered in the oil samples from the district, and a little amount of benzocarbazoles was detected only in a few oil samples. However, no dibenzocarbazoles has been discovered in the district. Based on the distributions of G1, G2 and G3 structural types of C2-alkylcarbazoles, the ratio of C3-carbazoles / C2-carbazoles, and the relative amounts of alkylcarbazoles and alkylbenzocarbazoles, it is suggested that the oils of the Carboniferous C3 reservoir in the Central Tarim district may migrate laterally to the top position of Structure No.4 of the district from its northwest side and southeast side. And the oils in this district might be undergone quite a long distance migration.