Bar’s work seeks to quantify and understand the non-recoverable deformation that accrues above subduction megathrusts over multiple seismic cycles. To do so, he develops landscape analysis tools that infer the spatial pattern of long-term uplift at active margins, and compares it to simple mechanical models informed by seismological and geodetic observations. His research is funded by an Emergence(s) Ville de Paris grant.
Léo Petit (co-advised with A. Schubnel & H. Bhat, 2019-2023)
Léo’s research aims at developing novel parameterizations of brittle deformation in long-term tectonic models. Léo specifically works on low-temperature deformation involving the slow growth of micro-fractures that nucleate around rock defects, and may eventually coalesce to form faults. The goal of this new framework is to better describe the strain rate dependence, dilatancy, and creep properties of the upper crust, and relate them to small-scale phenomena that are observable in rock deformation experiments.
Antoine Demont (co-advised with M. Cannat, 2021–)
Antoine’s thesis focuses on the growth of large-offset detachment faults in the oceanic lithosphere, and its possible modulation by rheological factors. These include rates and intensity of brittle strain softening, dilatancy and frictional weakening due to alteration reactions, and viscous strength in the lower lithosphere. His work aims at relating the morphology of detachment-bounded structures to a range of deformation mechanisms documented at the outcrop and sample scale along the Southwest Indian Ridge and Mid-Atlantic Ridge.
Emeline Caujolle (Summer 2021, Spring 2023)
Emeline models the effect of sediment creep on strain localization at the shallowest levels of the Earth’s crust, in order to understand the formation of buried, or “blind” thrust faults, which accumulate slip but do not reach the Earth’s surface.
Under the group meeting tree, Summer 2021
Past group members
Qingkai Fan (visiting PhD student, Peking U., 2018–2019)
Qingkai spent a year of his doctoral studies at ENS as a CSC Scholarship recipient. During his visit, he investigated the conditions under which oceanic detachment faults could act as fluid pathways in young oceanic lithosphere. He also developed models of hydrothermal circulation driven by intermittent magmatic intrusions to better understand the thermal regime of magma-starved ultraslow-spreading ridges. This work is now published in JGR.
Hugo Lestrelin (co-advised with P. Dublanchet, Spring 2021)
Hugo worked on the partitioning of magmatic and tectonic deformation at rifts and mid-ocean ridges on decadal time scales. He specifically modeled the way a dike intrusion perturbs the seismic cycle of a rift border fault, and, conversely, the way fault slip may affect the magma plumbing system. Hugo is currently a PhD student at Géoazur.
Clara Sfez (Spring 2021)
Clara studied the evolution of bedrock landscapes where erosion rates are set by the pace of micro-fracture growth, which is itself driven by topographic and tectonic stresses. She designed a theoretical model in which relief evolves self-consistently based on its own gravitational stress field and sub-critical crack growth rules.
Kim Moutard (Summer 2021)
Kim used numerical models of hydrothermal circulation to assess how inflation and deflation of magma reservoirs affect the permeability of the oceanic crust, and the temperature of fluids venting at the seafloor.
Clément de Sagazan (Summer 2018 & Fall 2019)
Clément studied the peculiar tectonics of the Andaman sea spreading center, which can be thought of as a slow mid-ocean ridge subjected to rapid sedimentation rates. He used thermo-mechanical models to characterize the effect of magmatic accretion and sediment deposition on the growth of normal faults, which are unusually long-lived at this spreading center. His work is now published in Geology. Clément is currently a PhD student at IPGP.