@article{fdi:010084571,
  title = {{M}odels of convection and segregation in heterogeneous partially molten crustal roots with a {VOF} method - {I} : flow regimes},
  author = {{L}ouis-{N}apoleon, {A}. and {B}onometti, {T}. and {G}erbault, {M}uriel and {M}artin, {R}. and {V}anderhaeghe, {O}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e investigate numerically some thermomechanical conditions for the development of crustal scale diapirism and convection in a heterogeneous continental crust independently from the action of regional tectonics. {H}ere, we consider a hot crust, with unmolten and partially molten domains of specific temperature and strain-rate dependent power-law rheologies. {W}e take advantage of the volume of fluid ({VOF}) method to capture the coalescence and separation of deformable inclusions in the partially molten domain. {T}he inclusions, of several hundred metres in size, are more or less dense and viscous with respect to the ambient medium (they also behave with a power-law rheology). {W}e restrict our study to a 20 {M}yr time scale, during which gravitational dynamics may dominate over lateral tectonics and lithospheric thermal re-equilibration. {T}he motion of these inclusions during the development of gravitational instabilities displays distinct flow regimes that depend on two {R}ayleigh numbers denoted {R}a-{UM} and {R}a-{PM}, for the unmolten and partially molten rock properties, respectively. {A} 'suspension' regime occurs at high {R}a-{UM} and high {R}a-{PM}, in which most of the light compositional heterogeneities remain entrained in the convective cells. {I}n contrast at low {R}a-{UM} and high {R}a-{PM}, a 'layering' regime is characterized by merging of the light inclusions as floating clusters below the rigid upper crustal lid. {T}his regime occurs in association with a sharp viscosity gradient at upper-to-middle crust transitional depths. {I}n these two regimes, the dense inclusions accumulate at the bottom of the partially molten zone. {F}inally at moderate {R}a-{PM}, a 'diapiric' regime reflects the segregation of the heavy and the light inclusions, respectively downward and upward, without global convection. {T}hese numerical experiments lead to a first order evaluation of the physical parameters required for the segregation of deformable inclusions of variable densities and convection, in a partially molten crust, and provide insights on the conditions for the development of migmatite domes. {G}eological data indicate that these processes likely occur in a large number of settings from {A}rchean to {P}hanerozoic times, and contribute to the differentiation of the continental crust.},
  keywords = {{C}omposition and structure of the continental crust ; {N}umerical modelling ; {D}iapirism ; {D}ynamics: gravity and tectonics ; {H}eat generation and transport ; {R}heology: crust and lithosphere},
  booktitle = {},
  journal = {{G}eophysical {J}ournal {I}nternational},
  volume = {229},
  numero = {3},
  pages = {2047--2080},
  ISSN = {0956-540{X}},
  year = {2022},
  DOI = {10.1093/gji/ggab510},
  URL = {https://www.documentation.ird.fr/hor/fdi:010084571},
}