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The Longmenshan Range is a tectonically composite intracontinental orogen.Its structure,deformation and spatial evolution reflect multiple kinematic eposides and variable dynamics especially during Post-Middle to Post-Late Triassic time.Field work,lower-temperature thermochronological data and U-Pb detrital zircon ages indicate document down-dip zonation and along-strike segmentation demonstrated by significant differences in geological structure,intensity of deformation and deformationinvolved strata,uplift and cooling processes.Low-temperature thermochronology and U-Pb detrital zircon ages reveal a period of tectono-thermal quiescence with slow uplift and cooling during post Early Norian to Rhaetian orogeny,followed by rapid cooling and uplift during the Late Cenozoic accompanied by coeval southeastward thrusting and southwestward propagation of defromation.The Longmenshan Range formed by S-N striking compression exerted by the Qinling orogen,E-W striking compression by the Tibetan Plateau and SE-striking compression by the Yangtze Plate.We propose a southwestward propagation model for the Longmenshan Range based our observations of zonation,segmentation and composite evolutional processes during the Late Triassic superimposed by development of the differential uplift and cooling processes that shows southern segments of the Longmenshan Range during Post-Jurassic times.
The Longmenshan Range is a tectonically composite intracontinental orogen. Its structure, deformation and spatial evolution reflect multiple kinematic eposides and variable dynamics especially during Post-Middle to Post-Late Triassic time. Field work, lower-temperature thermochronological data and U-Pb detrital zircon сinside document down-dip zonation and along-strike segmentation demonstrated significant difference in geological structure, intensity of deformation and deformation in vaporized strata, uplift and cooling processes. Low-temperature thermochronology and U-Pb detrital zircon ages reveal a period of tectono-thermal quiescence with slow uplift and cooling during post Early Norian to Rhaetian orogeny, followed by rapid cooling and uplift during the Late Cenozoic accompanied by coeval southeastward thrusting and southwestward propagation of defromation. Longmenshan Range formed by SN striking compression exerted by the Qinling orogen, EW striking compression by the Tibetan P lateau and SE-striking compression by the Yangtze Plate. We propose a southwestward propagation model for the Longmenshan Range based our observations of zonation, segmentation and composite evolutional processes during the Late Triassic superimposed by development of the differential uplift and cooling processes that shows southern segments of the Longmenshan Range during Post-Jurassic times.