Application for the fission-track thermal evolution history in the formation age of Yaoshan formation, Tan Mountain

摘要

To make sure the formation age of Yaoshan formation is the key to carry out the stratigraphic division and correlation, to reconstruct prototype basin and to evaluate regional resources in west margion Ordos basin. The tectonic-heat event and evolutionary process were precisely recorded by clastic filler in basin and can be reconstructed by means of fission track of apatite and zircon. The thermal history simulation result is verified by the analysis of similarities and differences between the fission track thermal history and regional tectonic-thermal or tectonic evolution history. The formation age of clastic rock can be assured by the buried warming time of confidence thermal history simulation result. The example of sandstone sample, which locate in Yaoshan formation, Tanshan Mountain, demonstrates that the buried warming time was between 195 and 170Ma. It shows Yaoshan formation was deposited in early-middle Jurassic. The method is very important and critical to judging the formation age of these clastic rocks, which lack of fossil and lava interlayer.