Low Temperature Thermal History Reconstruction Based on Apatite Fission-Track Length Distribution and Apatite U-Th/He Age Using Low-T Thermo

Low temperature thermochronology plays a key role in the study of the tectonic evolution of the upper crust. History modeling of apatite fission-track requires the apparent age and the confined track-length distribution of spontaneous tracks. Obtaining length data does not require either thermal neutron irradiation or LA-ICP-MS measurements of the uranium content of the grains. This paper attempts to decouple the apatite fission-track age from the apatite fission-track length, but to combine the fission-track lengths with the respective apatite U-Th/He age to model the thermal history. The experiments were designed and conducted using a new Mathematica® modeling software "Low-T Thermo". Results of this modeling show that the thermal history modeling of apatite U-Th/He and fission-track ages can constrain the apatite fission-track length thermal history in the He partial retention zone and fission-track partial annealing zone, respectively. It implies that this combination of apatite fission-track length and apatite U-Th/He age has not been implemented before but is presented here as an alternative way of determining thermal histories without the addition of apatite fission-track age.