K-feldspar MDD (Multiple Diffusion Domain) and fission track are two commonly-used methods in low closure temperature thermal chronometry. By modeling both the feldspar 39Ar/40Ar data and the fission track age and track-length data, the thermal history that sample underwent can be revealed and the effective temperature range of both feldspar 39Ar/40Ar method and fission track method is extended. Because of the multiple resolution of modeling, it is important to restrict the modeling process to gain a reasonable result, though it seems difficult. Three rapid cooling events, occurring at 130~150 Ma, 30~40 Ma and 5~10 Ma respectively, in northern margin of Qaidam Basin are revealed by feldspar MDD method and fission track method.