Apatite fission-track (AFT) and structural data outline the Late Cretaceous−Cenozoic history of the southern Tan-Lu fault zone (TLFZ), one of Asia's major faults, the Triassic–Jurassic Dabie orogen, Earth's largest track of ultrahigh-pressure rock exposure, and its foreland, the Yangtze foreland fold-thrust belt. The fission-track analyses utilized the independent (φ-), Z- and ξ-methods for age determination, which yielded within error identical ages. Ages from Triassic–Jurassic syn-orogenic foreland sediments are younger than their depositional age and thus were reset. A group of ages records rapid cooling following shallow emplacement of granitoids of the widespread latest Jurassic−Early Cretaceous “Yanshanian” magmatism. Most ages are 90 to 55 Ma and document cooling following reheating at 110–90 Ma, the time when the basement units of the Dabie Shan were last at >200 °C. This cooling coincides with rifting marked by the Late Cretaceous−Eocene red-bed deposition in eastern China. During this period, the Dabie basements units exhumed in the footwall of the Tan-Lu fault with the Qianshan basin in the hanging wall; the associated stress field is transtensional (NW-trending principal extension direction). The youngest fission-track ages and temperature–time path modeling point to enhanced cooling in the footwall of the Tan-Lu and associated faults at 45±10 Ma. The related stress field is transtensional, with the principal extension direction changing trend from NW to W. It may be the far-field expression of the India–Asia collision superposed on the back-arc extension setting in eastern China. A regional unconformity at ∼25 Ma marks an upper bound for the inversion of the Late Cretaceous−Eocene rift structures. During the Neogene, further subsidence in the eastern China basins was accommodated by sub-horizontal NE–SW extension, and followed by the presently active NW–SE extension. The Tan-Lu fault along the eastern edge of the Dabie Shan had normal and then sinistral-transpressive motion during the Late Cretaceous−Eocene. Its motion changed during the Neogene from sinistral transtensive to normal and then to its present dextral transtensive activity.
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