Melting at the oceanic LAB: contribution to the evolution of lithospheric mantle and the small-scale seamounts

Session ID#: 24435

Session Description:
The formation, evolution and recycling of oceanic lithosphere is critical to understand the asthenosphere-lithosphere chemical exchange. The oceanic lithospheric mantle is commonly interpreted as the depleted residue after MORB extraction and the presence of low-degree melts has been proposed to explain the geophysical properties at the LAB. The discovery of petit-spot volcanoes associated with plate flexure supports the presence of this low-degree melts at the base of the lithosphere, but also open news questions. Is the formation of the countless seamounts observed in oceanic basins associated with similar processes? Could the percolation of melts across the lithosphere explain the geophysical anomalies recorded within the oceanic lithosphere and modify the composition of the oceanic lithosphere including volatiles? This session invites contributions from geologists, geochemists, petrologists, numerical modelers, and geophysicists who investigate the physical and chemical nature of the oceanic lithosphere and LAB and its role in the formation of seamounts.
Primary Convener:  Naoto Hirano, Tohoku University, Sendai, Japan
Conveners:  Sebastien Pilet, University of Lausanne, Lausanne, Switzerland and Kiyoshi Baba, University of Tokyo, Bunkyo-ku, Japan
Index Terms:

3045 Seafloor morphology, geology, and geophysics [MARINE GEOLOGY AND GEOPHYSICS]
3075 Submarine tectonics and volcanism [MARINE GEOLOGY AND GEOPHYSICS]
3621 Mantle processes [MINERALOGY AND PETROLOGY]
8120 Dynamics of lithosphere and mantle: general [TECTONOPHYSICS]

Abstracts Submitted to this Session:

Kei Shimizu, Carnegie Institution for Science, Department of Terrestrial Magnetism, Washington, DC, United States and Alberto E Saal, Brown University, Department of Earth, Environmental and Planetary Sciences, Providence, RI, United States
Annelore Bessat1, Sebastien Pilet1, Thibault Duretz2 and Stefan M Schmalholz1, (1)University of Lausanne, Lausanne, Switzerland, (2)University of Lausanne, ISTE, Lausanne, Switzerland
Sebastien Pilet1, Othmar Müntener1, Thibault Duretz2 and György Hetényi1, (1)University of Lausanne, Lausanne, Switzerland, (2)University of Lausanne, ISTE, Lausanne, Switzerland
Kiyoshi Baba1, Natsue Abe2, Naoto Hirano3 and Masahiro Ichiki3, (1)University of Tokyo, Bunkyo-ku, Japan, (2)JAMSTEC Japan Agency for Marine-Earth Science and Technology, Kanagawa, Japan, (3)Tohoku University, Sendai, Japan
Saikiran Tharimena1, Catherine Rychert1, Nicholas Harmon1 and Paul White2, (1)University of Southampton, Southampton, United Kingdom, (2)University of Southampton, Institute of Sound and Vibration Research, Southampton, United Kingdom
Pilar Madrigal Quesada, University of Costa Rica, San Jose, Costa Rica and Esteban Gazel, Cornell University, Earth and Atmospheric Sciences, Ithaca, NY, United States