Éditeur(s) : HAL CCSD American Geophysical Union
Résumé : International audience
[1] Based on geological and geophysical data collected from the West Philippine Basin and its boundaries, we propose a comprehensive Cenozoic history of the basin. Our model shows that it is a back arc basin that developed between two opposed subduction zones. Rifting started around 55 Ma and spreading ended at 33/30 Ma. The initial spreading axis was parallel to the paleo-Philippine Arc but became inactive when a new spreading ridge propagated from the eastern part of the basin, reaching the former one at an R-R-R triple junction. Spreading occurred mainly from this second axis, with a quasi-continuous counterclockwise rotation of the spreading direction. The Gagua and Palau-Kyushu ridges acted as transform margins accommodating the opening. Arc volcanism occurred along the Palau-Kyushu Ridge (eastern margin) during the whole opening of the basin, whereas the paleo-Philippine Arc decreased its activity between 43 and 36 Ma. The western margin underwent a compressive event in late Eocene-early Oligocene time, leading to the rising of the Gagua Ridge and to a short subduction episode along Eastern Luzon. In the western part of the basin, the spreading system was highly disorganized due to the presence of a mantle plume. Overlapping spreading centers and ridge jumps occurred toward the hot region and a microplate developed. Shortly after the end of the spreading, a late stage of amagmatic extension occurred between 30 and 26 Ma in the central part of the basin, being responsible for the deep rift valley that cut across the older spreading fabric. Citation: Deschamps, A., and S. Lallemand, The West Philippine Basin: An Eocene to early Oligocene back arc basin opened between two opposed subduction zones,
ISSN: 2169-9313

hal-01261388
https://hal.archives-ouvertes.fr/hal-01261388
https://hal.archives-ouvertes.fr/hal-01261388/document
https://hal.archives-ouvertes.fr/hal-01261388/file/DeschampsJGR2002.pdf
DOI : 10.1029/2001JB001706

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Crystal growth driven by a flowing solution is modeled for a flow with low Reynolds number using a computational dynamic software. Considering equivalent crystallographic faces, the chemical flux is calculated along upstream and downstream faces. Upstream flux is higher compared to downstream and leads to a symmetry breakdown of the crystal shape and develops mirror symmetry parallel to the flow velocity. Moreover the ratio of these two fluxes (upstream / downstream) gives a quantitative relation between the relative crystal growth rate and the flow velocity. Thus, using an inverse method, the flow direction and velocity can be deduced by the study of the variation of the growth band thicknesses of equivalent crystallographic faces. This new method was applied to the formation of metasomatic tourmalinite associated with a leucogranite sill. The approach is complemented by a study of the chemistry of the tourmaline. In the studied case, the application of the new method gives the high fluid velocities in pores (10-3 - 10-4 m/s) during metasomatism. Equivalent Darcy velocities are estimated and discussed accounting for the major role played by the regional deformation. Finally, a two-stage tectono-hydrodynamic model is proposed for the metsomatism. The first stage is genetically linked to the sill injection, and the second is characterized by a wider event with hydrothermal flow passing along the leucogranite sills.
ISSN: 0012-821X

Droits : info:eu-repo/semantics/OpenAccess
insu-00352307
https://hal-insu.archives-ouvertes.fr/insu-00352307
https://hal-insu.archives-ouvertes.fr/insu-00352307/document
https://hal-insu.archives-ouvertes.fr/insu-00352307/file/Sizaret_et_al_final.pdf
DOI : 10.1016/j.epsl.2009.01.013

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
In northeastern Vietnam, the major tectonic episode responsible for nappes emplacement is Triassic. These allochtonous structures are intruded by granitic melts. Two post-tectonic massifs showing no sign of deformation have been dated by the LA-ICPMS zircon U-Pb techniques. Dating reveals a multiphase history with zircon cores showing evidence of Proterozoic magmatism. The emplacement of the Phia Bioc granite intrusive in allochtonous units is 248-245 Ma, an age which assesses a younger limit for the major nappes tectonic. This tectonic could be synchronous of the tectonometamorphic strike-slip faulting events (250-245 Ma) defined in the Truong Son Belt as the Indosinian orogen. The Phia Bioc intrusion is probably linked with the intra-plate magmatism of the Emeishan Large Igneous Province or with magma- tism associated with the Paleotethys closure. The age of the Phia Oac granite intrusion in displaced units is much younger, at 87.3 ± 1.2 Ma. This granite is probably linked to the magmatic activity produced dur- ing the Paleo-Pacific plate subduction under the SE Asia continental plate during the Mesozoic. Although the Cenozoic Red River fault system is close to these two plutons, this last thermotectonic episode has not been strong enough to disturb the U/Pb system. Zircons rims do not show any Tertiary magmatic or meta- morphic overprint.
ISSN: 0743-9547

hal-00681725
https://hal.archives-ouvertes.fr/hal-00681725
DOI : 10.1016/j.jseaes.2011.12.012

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The interpretation of high-resolution 2D marine seismic profiles together with the analysis of sea-bottom cores allowed a stratigraphic and structural framework of the Provence continental shelf to be proposed. The integration of onshore and offshore stratigraphy, structure and geomorphology provided new insights into Messinian paleotopography and paleohydrography. A geological map of the offshore Provence continental shelf, isobath map of the base Plio-Quaternary surface are presented for the first time in this area. The base Plio-Quaternary surface is a polyphased unconformity that is composed of deep canyons developed by fluvial erosion during the Messinian event, and wave-cut surfaces formed during post-Messinian transgressions. The study evidenced a deep, E-W-trending canyon (Bandol canyon) connected to the head of the Cassidaigne canyon, and filled with up to 600 m-thick Plio-Quaternary deposits. The development of canyons on the Provence margin during the Messinian event was dominantly controlled by the lithology and structure of pre-Messinian formations. A map of the Messinian paleo-drainage network is proposed to explain the presence of deep canyons in the Eastern area and the lack of incision in the Western area. An underground karst drainage scheme is proposed, linked with the current submarine Port-Miou spring.
ISSN: 0264-8172

insu-01009592
https://hal-insu.archives-ouvertes.fr/insu-01009592
https://hal-insu.archives-ouvertes.fr/insu-01009592/document
https://hal-insu.archives-ouvertes.fr/insu-01009592/file/Mar-Pet-Tassy.pdf
DOI : 10.1016/j.marpetgeo.2014.05.001

Éditeur(s) : London : printed for the author
Résumé : "Epigraphe au verso du titre : "Qui maris atque telluris stupendas metamorphoses contemplari cupit, vix ullibi terrarum reperiet commodiorem occasionem" Lin. Orat. Edition originale - Dédicace au prince de Galles. - Liste des souscripteurs. - Index. - Bandeaux et culs-de-lampe gravés sur bois - 49 planches gravées sur cuivre (38 pour la flore et 11 pour la faune) d'après G.D. Ehret et F. Garden. - Manquent les 2 cartes dépliantes de la Jamaïque. - Demi-reliure papier peigné, fin 18e-début 19e siècle. - Quelques annotations manuscrites au crayon, écriture du 19e siècle. Un feuillet volant annoté inséré entre les p. 222 et 223. - Plante séchée insérée entre les p. 350 et 351. - Cachet de la bibliothèque de la Ville de Bordeaux Brunet, I, 1282. - Chalmers, The General Biographical Dictionary, VII, p. 134. - Sabin, 8670"
Siècle(s) traité(s) : 18
Droits : Domaine public
Provenance : Ville de Bordeaux. Bibliothèque municipale
Permalien : http://www.manioc.org/patrimon/BBX17028
BBX17028

Éditeur(s) : Paris : Firmin Didot Frères

Droits : Domaine public
Provenance : Archives territoriales de Guyane
Permalien : http://www.manioc.org/patrimon/GAD12002
GAD12002

Éditeur(s) : Londres : P. S. King and Son
Siècle(s) traité(s) : 19
Provenance : Université Caen Normandie. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/CAE19037
CAE19037