The Himalayan-Tibetan orogen system serves as the modern paradigm for understanding convergence-related processes in orogenic belts. The advancements made studying the region have been applied to other ancient orogeni...The Himalayan-Tibetan orogen system serves as the modern paradigm for understanding convergence-related processes in orogenic belts. The advancements made studying the region have been applied to other ancient orogenic belts leading not only to a better understanding of their development, but also of secular changes in collisional processes. As more advanced methodologies are introduced and utilized in geological research, the type, scale, and quality of data available enable quantification of geological processes not previously possible. These complex and robust datasets now form the core of many of the research projects undertaken across the Himalaya and continue to provide unprecedented insight into the myriad different aspects of the evolution of the collisional system.展开更多
In this contribution,we analyzed a pair of mafic samples collected from a recently identified shear zone and its proximal footwall from the Manicouagan Imbricate Zone(MIZ)of the central Grenville Province,Québec,...In this contribution,we analyzed a pair of mafic samples collected from a recently identified shear zone and its proximal footwall from the Manicouagan Imbricate Zone(MIZ)of the central Grenville Province,Québec,Canada.Titanite petrochronology,metamorphic phase equilibria modelling,trace element thermometry,and electron backscattered diffraction data were used to define a Pressure-Temperature-timeDeformation path for the two samples.An interconnected dislocation network within titanite grains,as outlined with Kerneled Average Misorientation maps,are spatially correlated with variation in the U-Pb system but not with that observed for trace element These results suggest that the U-Pb system was decoupled from trace and rare earth elements and that deformation,rather than interface-coupled dissolution-precipitation reactions or re-crystallisation,was the main driver for this decoupling.In addition to highlighting a potential pitfall of titanite petrochronology,our P-T-t-D path reveals that ductile shear zones were active later than previously suggested within the MIZ.展开更多
文摘The Himalayan-Tibetan orogen system serves as the modern paradigm for understanding convergence-related processes in orogenic belts. The advancements made studying the region have been applied to other ancient orogenic belts leading not only to a better understanding of their development, but also of secular changes in collisional processes. As more advanced methodologies are introduced and utilized in geological research, the type, scale, and quality of data available enable quantification of geological processes not previously possible. These complex and robust datasets now form the core of many of the research projects undertaken across the Himalaya and continue to provide unprecedented insight into the myriad different aspects of the evolution of the collisional system.
基金funded in part by the Ministère des Ressources naturelles du Québec contribution no.8449–2021-2022–04 under the supervision of AMoukhsil and partially funded by an NSERC-Discovery grant RGPIN-2014-04593 hosted by F.Gervais.
文摘In this contribution,we analyzed a pair of mafic samples collected from a recently identified shear zone and its proximal footwall from the Manicouagan Imbricate Zone(MIZ)of the central Grenville Province,Québec,Canada.Titanite petrochronology,metamorphic phase equilibria modelling,trace element thermometry,and electron backscattered diffraction data were used to define a Pressure-Temperature-timeDeformation path for the two samples.An interconnected dislocation network within titanite grains,as outlined with Kerneled Average Misorientation maps,are spatially correlated with variation in the U-Pb system but not with that observed for trace element These results suggest that the U-Pb system was decoupled from trace and rare earth elements and that deformation,rather than interface-coupled dissolution-precipitation reactions or re-crystallisation,was the main driver for this decoupling.In addition to highlighting a potential pitfall of titanite petrochronology,our P-T-t-D path reveals that ductile shear zones were active later than previously suggested within the MIZ.