ssion-track analyses of apatite and zircon show that an uplift-cooling event occurred in Qinshui basin 26.2-11.5Ma ago. It occurred earlier in the northern and southern parts

and later in the central part. Qinshui basin experienced a large uplift-cooling event from Oligocene to Miocene

as a result

the formation temperature decreased and the hydrocarbon generating process in the Permo-Carboniferous coal measure strata ceased.