%0 Conference Proceedings %F Poster %T What we can learn from peak temperatures profiles in inverted metamorphic sequences %+ Géosciences Rennes (GR) %A Duprat-Oualid, Sylvia %A Yamato, Philippe %< avec comité de lecture %B European Geosciences Union General Assembly 2016 %C Vienne, Austria %V 18 %P EGU2016-959 %8 2016-04-12 %D 2016 %Z Sciences of the Universe [physics]/Earth Sciences/TectonicsConference poster %X Inverted metamorphic sequences correspond to the stacking of structural units through which the metamorphicpeak temperatures progressively increase upwards. Such thermal profiles, already studied for years, are characteristicof lithospheric-scale thrust zones. Nevertheless, the processes allowing their formation still remaincontentious. Several processes can, indeed, lead to peak temperatures inversion: heat advection, shear heating, indepthaccretion and/or erosion (allowing the exhumation of the overthrusting block). Furthermore, heat diffusionalso has an important effect on temperatures distribution on both sides of the thrust. Each one of these processesdistinctly impacts on the metamorphic thermal field in the vicinity of the thrust zone. However, their respectiveinfluences were never clearly analyzed and compared despite their crucial importance for the interpretation of theinverted peak temperatures signatures.Here, we thus propose to address this shortcoming by using two-dimensional numerical models simulatingintra-continental thrusts systems. To do so, we combine a parametric numerical study and the “analytical characterization”of the computed inverted peak temperatures recorded, in our models, along profiles perpendicularto the thrust zone. The parametric combinations, including kinematic setting (i.e. convergence, erosion andaccretion), thermal properties, mechanical strength and heat sources, control the processes into play during thethrust activity whose relative importances can be quantified. When the resulting peak temperatures profiles presenta noticeable inversion, they are converted into a function of approximation characterized by six parameters. Thesesix outputs then constitute the keys to quantitatively decipher the inversions features, not only in terms of spatialextent and intensity over time, but also by characterizing the peak temperatures trends on either sides of thedomain of inversion. This numerical and analytical coupled approach then allows to give the significance of peaktemperatures profiles in relation with the different processes into play.Our results allow to quantify the influence of each process (i.e. heat diffusion, heat advection, shear heating,erosion and accretion) on the different features of inverted peak temperatures signatures. They show that noneof them can be considered alone. Finally, the function of approximation used in this study, allowing to efficientlyfit a discrete dataset to a continuous signal, can also be applied to natural peak temperatures estimations followingthe same way. We thus propose to illustrate this on the example of the inverted metamorphic sequence associatedto the Main Central Thrust zone in the Himalayas. %G English %L insu-01309387 %U https://insu.hal.science/insu-01309387 %~ INSU %~ UNIV-RENNES1 %~ UR2-HB %~ CNRS %~ GR %~ OSUR %~ UR1-HAL %~ UR1-SDLM %~ GR-3T %~ UNIV-RENNES2 %~ TEST-UNIV-RENNES %~ TEST-UR-CSS %~ UNIV-RENNES %~ INRAE %~ UR1-ENV %~ GR-DEMO