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Papers by Laurent Jolivet

Nature Communications, Sep 17, 2018

EGU General Assembly Conference Abstracts, Apr 1, 2009

Comptes Rendus. Géoscience

HAL (Le Centre pour la Communication Scientifique Directe), 2019

Journal of Asian Earth Sciences

HAL (Le Centre pour la Communication Scientifique Directe), Apr 1, 2016

HAL (Le Centre pour la Communication Scientifique Directe), Nov 25, 2019

The transfer and emplacement dynamics of highly crystallised (φ >∼0.6) magmas are mostly depen... more The transfer and emplacement dynamics of highly crystallised (φ >∼0.6) magmas are mostly dependent on the interconnected crystal-framework controlling the tortuosity of the residual melt flow and capable of transmitting deviatoric high stresses. Crystal fraction, size distribution, and strain rate control the development of crystal fabrics and strain localisation. How localised structures potentially promote the transfer of residual gas and melts in hardly moveable late magmatic mushes is a critical question that remains largely undocumented.

Bulletin de la Société Géologique de France, 2001

We present new structural and metamorphic data on the Schistes Lustres complex which occupies a c... more We present new structural and metamorphic data on the Schistes Lustres complex which occupies a central position in the western Alps between the external LP and the internal UHP domains (e.g., the Dora Maira massif). Metamorphic conditions are shown to increase progressively from west to east from ca. 12-13 kbar/300-350 degrees C to 20-21 kbar/450-500 degrees C close to the Dora Maira massif. Two distinct exhumation episodes are recognized: (1) A pervasive east-vergent ductile D2 event, with a large component of vertical shortening, took place under low blueschist-facies to greenschist-facies conditions. This event is responsible for most of the exhumation of the Schistes Lustres complex as well as for the preservation of carpholite occurrences at its front, and took place during the period 50-40 Ma. (2) A west-vergent ductile-to-brittle, highly non-coaxial, extensional D3 event subsequently developed, with a deformation intensity decreasing from east to west. This event took place ...

In Neogene times, the whole Mediterranean Sea was the center of an intense magmatic activity. Thi... more In Neogene times, the whole Mediterranean Sea was the center of an intense magmatic activity. This post-collisional magmatism produced a large amount of volcanic edifices through the Alpine belts, together with some intrusives. These plutonic bodies can be associated with skarn-type mineralization, well-known in Elba Island or Serifos Island (Cyclades), where they are generally exhumed by detachment faults. In Morocco, the plutons hosted by the Beni Bou Ifrour massif are connected to the biggest skarn-type iron concentrations of the country (production > 60 Mt, reserves ≈ 25 Mt). The purpose of this work is to explain the late uplift of this massif and subsequent exhumation of the intrusives. As a final product of the Africa-Eurasia plate convergence since ca. 70 Ma, the Rif Mountains constitute the westernmost segment of the Mediterranean Alpine belts. In the oriental part of this range, volcanic summits and Paleozoic to Mesozoic massifs outcrop in the surrounding Mio-Pliocene p...

Gneiss Domes in Orogeny, 2004

Lithos, 2003

... HP metamorphism on the Dilek peninsula 7.3. ... kyanite-, staurolite-, chloritoid-, and silli... more ... HP metamorphism on the Dilek peninsula 7.3. ... kyanite-, staurolite-, chloritoid-, and sillimanitemicaschists, quartzites, garnet amphibolites, pelitic and psammitic gneisses, with black marble intercalations (Dürr, 1975), (Akkök, 1983), (Ashworth and Evirgen, 1984), (Sengör ...

Mantle convection drives plate tectonics and the size, number and thermotectonic age of plates co... more Mantle convection drives plate tectonics and the size, number and thermotectonic age of plates codetermines the convection pattern. However, the degree of coupling of surface deformation and mantle flow is unclear. The use of SKS waves seismic anisotropy shows a coherence of mantle and surface deformation, but significant examples depart from this scenario. We review geological observations and present kinematic reconstructions of the Aegean and Middle East and 3D numerical models to discuss the role of asthenospheric flow in crustal deformation. At the scale of the Mediterranean backarcs, lithosphere-mantle coupling is effective below the most extended regions as shown by the alignment of SKS fast orientations and stretching directions in MCCs. In the Aegean, the directions of mantle flow, crustal stretching and GPS velocities are almost parallel, while, below the main part of the Anatolian plate, SKS fast orientations are oblique to GPS velocities. When considering the long-term geological history of the Tethyan convergent, one can conclude that asthenospheric flow has been an important player. The case of Himalaya and Tibet strongly supports a major contribution of a northward asthenospheric push, with no persistent slab that could drive India after collision, large thrust planes being then decoupling zones between deep convection and surface tectonics. The African plate repeatedly fragmented during its migration, with rifting of large pieces of continents that had then been moving northward faster than Africa (Apulia, Arabia). This also suggests a dominant role of an underlying flow at large scale, dragging and mechanically eroding plates and breaking them into fragments, then passively carried. Mantle flow thus seems to be able to carry plates toward subduction zones, break-away pieces of plates, and deform backarc upper crust where the lithosphere is the thinnest. Most numerical models of lithospheric deformation are designed such that strain is a consequence of kinematic boundary conditions (push or pull on lateral sides), and rarely account for basal stresses due to mantle flow. On the other hand, convection models often treat the lithosphere as a single-layer stagnant lid with vertically undeformable surface. There is thus a gap between convection models and lithospheric-scale geodynamic models. We test different degrees of coupling using 3-D lithospheric deformation models. Preliminary results suggest that lithosphere can be carried by asthenospheric flow, which may lead to plate fragmentation, especially if this flow is applied on a large surface and involves mantle upwelling. However, the presence of a ductile lower crust inhibits the upward transmission of stresses. A highly extended crust in a hot environment such as a backarc domain, with no lithospheric mantle and a ductile lower crust in direct contact with asthenosphere, is more prone to follow the mantle flow than a thick and stratified lithosphere.

Tectonics, 1996

A major problem posed by the geology of Crete is the horizontal contact of an upper unit without ... more A major problem posed by the geology of Crete is the horizontal contact of an upper unit without Miocene metamorphism onto a metamorphosed lower one with Early Miocene high pressure/low temperature (HP/LT) parageneses. This very sharp contact is roughly parallel to the major Oligo‐Miocene thrust planes which were reactivated as a large‐scale detachment which allowed exhumation of high‐pressure units. We describe the extensional deformation and the metamorphic evolution of the lower plate. Most first‐order deformation features relate to the retrogression from high‐pressure to low‐pressure conditions. A N‐S pervasive stretching is observed everywhere, often associated with a top‐to‐the‐north sense of shear. The extreme variation of thickness of the Phyllite‐Quartzite nappe (upper part of the lower plate) is probably the result of large‐scale boudinage similar to the one seen in large outcrops. The most important observation is the systematic occurrence of fresh carpholite immediately ...