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Introduction “Without hypotheses to test and prove or disprove, exploration tends to be haphazard and ill - directed. Even completely incorrect hypotheses may be very useful in directing investigation toward critical details .” ( Hess 1954 , p. 344) As the plate tectonics revolution gathered steam during the 1960s, linking sea-floor spreading with transform faults and subduction, it evolved into a paradigm to describe the Cenozoic to Mesozoic tectonics of the lithosphere—the strong outer layer of Earth above the weaker asthenosphere. The theory of plate tectonics

1 Introduction Among the tectonic plate boundaries, the Sumatra-Andaman Subduction Zone (SASZ; Kanamori, 2006 ) is one of the most active seismic source zones. Hazardous earth-quakes occur frequently along the SASZ, even within the short period of a human lifespan. For instance based on the Global Centroid Moment Tensor (GCMT; http://www.globalcmt.org/CMTsearch.html ) catalogue, 13 events of major earthquakes, M w 7.0-7.9 were reported within the 38-year period from 1976–2014 ( Fig. 1 ). Moreover during the last decade, 4 great earthquakes with M w ≥ 8.0 were

Introduction Together with mid-ocean ridges, subduction zones are the main sources of magma on Earth today, and there is increasing evidence that this has been so for billions of years (e.g., Tang et al. 2016 ). The continental crust is largely a product of calc-alkaline magmas produced in subduction zones. Accordingly, understanding magma generation in this environment is essential for any global picture of planetary evolution. Early studies suggested that calc-alkaline magmas may form by direct melting of the basaltic layer in the subducted slab ( Green and

American Mineralogist, Volume 95, pages 1214–1223, 2010 0003-004X/10/0809–1214$05.00/DOI: 10.2138/am.2010.3307 1214 Protracted oceanic subduction prior to continental subduction: New Lu-Hf and Sm-Nd geochronology of oceanic-type high-pressure eclogite in the western Dabie orogen Hao CHeng,1,2,* S. andrew duFrane,3 JeFFrey d. VerVoort,3 eizo nakamura,2 yong-Fei zHeng,4 and zuyi zHou1 1State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China 2Institute for Study of the Earth’s Interior, Okayama University, Tottori 682-0193, Japan 3

Review FLUIDS IN THE CRUST The chemical behavior of fluids released during deep subduction based on fluid inclusions† MaRia Luce FRezzotti1,* and SiMona FeRRando2 1Department of Earth and Environmental Sciences, University of Milano Bicocca, Piazza della Scienza 4, 20126 Milano, Italy 2Department of Earth Sciences, University of Torino, Via Valperga Caluso 35, Torino 10125, Italy abStRact This review combines fluid inclusion data from (HP-)UHP rocks with experimental research and thermodynamic models to investigate the chemical and physical properties of fluids

Illapel Mw=8.3 thrust earthquake rupture zone using GOCE derived gradients. Pure and Applied Geophysics, 174 (1) 47-75. https://doi.org/10.1007/s00024-016-1376-y Anderson, M. L., Alvarado, P., Zandt, G., and Beck, S., 2007.Geometry and brittle deformation of the subducting Nazca plate, central Chile and Argentina. Geophys. J. Int., 171(1), 419–434, doi:10.1111/j.1365-246X.2007.03483.x. Audin, L., P. Lacanb, P., Tavera, H., and Bondoux, F. 2008. Upper plate deformation and seismic barrier in front of Nazca subduction zone: The Chololo fault system and active tectonics

Introduction It is known that water plays a key role in mantle dynamics, including convection and magma generation (e.g., Hirth and Kohlstedt 1996 ; Asimow and Langmuir 2003 ; Bercovici and Karato 2003 ). An important question in this context is: How much water is transported into the mantle via subduction? Quartz eclogite typically contains several percent of hydrous minerals, predominantly calcic amphibole and zoisite. However, these minerals are not stable in coesite eclogite and, therefore, cannot account for the transport of water into mantle regions

Introduction Plate subduction is a geodynamic process that can transport water in the form of hydrous minerals from the surface reservoir down into the upper mantle and transition zone ( Zheng 2012 ) and perhaps the lower mantle. Among various hydrous minerals, the serpentine-group (containing about 13 wt% H 2 O) would break down at pressure-temperature conditions of the upper mantle to generate a series of dense hydrous magnesium silicate (DHMS) phases: such as Phase A [Mg 7 Si 2 O 8 (OH) 6 , 12 wt% H 2 O], chondrodite [Mg 5 Si 2 O 8 (OH) 2 , 5 wt% H 2 O], and

Introduction Orogenic peridotite bodies of various sizes are minor but significant components within high-pressure (HP) and ultrahigh-pressure (UHP) terranes in orogenic belts. They originated mainly from the mantle wedge above subducting crust and later were tectonically emplaced into the subduction channel to various depths (50–200 km) before exhumation ( Brueckner and Medaris 2000 ; Zhang et al. 2000 ; Scambelluri et al. 2008 ). Therefore, orogenic peridotites act as a natural laboratory to disclose the mass transfer from the downgoing slab into the

in subduction zones (mostly <~2.5 GPa) up to, but not including, the realm of extensive partial melting. There are many chemical elements to consider—too many for one paper—so the main theme will be mobility of the rare earth elements (REE). Other elements such as large ion lithophile (LILE) and high field strength (HFSE) elements will be discussed when appropriate. Historically, REE mobility has commonly been inferred to be relatively limited during hydrothermal or metamorphic fluid-rock interaction, and this is indeed the case in many environments (e.g., Taylor