关键词: 磷灰石, 裂变径迹, 含油气盆地, 地热史

Abstract: The theory of the fission-track dating is demonstrated simply and its application to the analysis of the thermal history of sedimentary basins is illustrated by case studies in USA and Australia.The fission-track data from Kang et al are reinterpreted.Reinterpretation indicates that a zone of annealing is located at a depth of 1600-2550 meters, a zone of partial annealing at 2550-3600 meters and a zone of cooling at 3600-9100 meters respectively.It is concluded that the parent rocks for appatites come from volcanic rocks of late Cretaceous and Tertiary and that the latest phase of cooling was initiated at the end of Tertiary(2.2 Ma ago)approximately at least, and involved a decrease in temperature of at least 13 degree C.The last conclusion is consistent with the results from paleotemperature studies.Both the zone of partial annealing and the zone of cooling are within the main zones of oilgeneration in Bohai Bay Basin, showing that the fission-track method is really suitable for the analysis of the thermal history of petroliferous basins.