Results 51 to 60 of about 31,153 (271)

Horizontal mantle flow controls subduction dynamics

Scientific Reports, 2017
It is generally accepted that subduction is driven by downgoing-plate negative buoyancy. Yet plate age –the main control on buoyancy– exhibits little correlation with most of the present-day subduction velocities and slab dips. “West”-directed subduction
E. Ficini, L. Dal Zilio, C. Doglioni, T. V. Gerya   +3 more
doaj   +1 more source

Interplay Between Mechanical and Petrochemical Models on the Fluid Extraction From Subduction Zones

Journal of Metamorphic Geology, EarlyView.
ABSTRACT The breakdown of hydrous minerals during subduction results in a densification of the rocks, producing volume changes that can trigger fluid pressure fluctuations and hydrofracturing. These volume changes are controlled by the Clapeyron slope of the reaction and are quantified here using a macroscopic framework that integrates a zero ...
Thorsten Andreas Markmann, Pierre Lanari   +1 more
wiley   +1 more source

Chemical Discrimination of Rutile From Different Metamorphic Source Rocks: Dealing With Hierarchical Data Structures in Random Forest Classification

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Rutile provides a wealth of petrochronological information in metamorphic geology and due to its high stability during processes of the sedimentary cycle, rutile takes a special position in sedimentary provenance analysis. Besides being one of the classical minerals datable using the U–Pb system, rutile incorporates a broad range of trace ...
Jan Schönig, Thomas Zack, Delia Rösel, Raimon Tolosana‐Delgado, Horst Marschall, Hilmar von Eynatten, Nils Keno Lünsdorf, Mona Lueder, Matthias Konrad‐Schmolke, Jesse B. Walters   +9 more
wiley   +1 more source

Coesite Discovery in Eclogites Confirms UHP Metamorphism in the Orlica‐Śnieżnik Dome (SW Poland)

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Eclogite lenses are exposed within the orthogneiss‐dominated core of the Orlica‐Śnieżnik Dome in the Sudetes, which forms the northeastern margin of the Bohemian Massif (Variscan Belt of Central Europe). The presence of coesite inclusions in garnet and omphacite confirms that these eclogites underwent ultrahigh‐pressure metamorphism.
Małgorzata Nowak, Lucie Tajčmanová, Marcin Dąbrowski, Iris Buisman, Jacek Szczepański   +4 more
wiley   +1 more source

Decoding Metamorphic Nanodiamonds Formation Through Their Internal Structures

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Metamorphic diamonds offer insights into Earth's evolution, modulating the global carbon cycle through subduction into the mantle and exhumation. However, the formation and internal structure of minute diamonds remain poorly understood. Here, we study the internal structures of diamond‐bearing inclusions from the Eastern Alps using state‐of ...
Tim Sotelšek, Marian Janák, Sašo Šturm, Sorour Semsari Parapari, Nik Gračanin, Kristian Radan, Mehmet Ali Gülgün, Stanislava Milovská, Mirijam Vrabec   +8 more
wiley   +1 more source

Tomographic Imaging of Slab Segmentation and Deformation in the Greater Antilles

Geochemistry, Geophysics, Geosystems, 2018
We present a new tomographic P wave model of the upper mantle in the east Caribbean region. The model was built using 3‐D finite frequency sensitivity kernels and ~20,000 teleseismic P and PP traveltime residuals from 535 events recorded across 130 ...
Cooper W. Harris, Meghan S. Miller, Robert W. Porritt   +2 more
doaj   +1 more source

Cryogenian Glacial Erosion and Tectonics as Agents of Crustal Recycling

Terra Nova, EarlyView.
ABSTRACT Zircon preserves evidence of recycling processes that link surface environments to the mantle. Combined δ18O‐εHf in zircon fingerprints magmatic sources and tracks how crustal material is reworked over time. We apply statistical analyses to a global compilation that apparently resolves shifts in zircon U–Pb, δ18O, and Lu‐Hf data spanning the ...
M. Seraine, C. J. Spencer, T. M. Gernon, T. Hincks, C. L. Kirkland, E. Rugen, L. DaSilva, H. Shafaii Moghadam, L. P. Soares, G. Fazio   +9 more
wiley   +1 more source

The secret to starting subduction is ... subduction

, 2020
Caroline Eakin, ANU The Earth's biggest earthquakes and most explosive volcanoes occur at subduction zones" where a tectonic plate (the seafloor itself) sinks bank into the Earth's interior. We've been able to compile 100 million years of existing evidence for Subduction Zone Initiation (SZI).
openaire   +1 more source

Giant Porphyry Copper Deposits Caused by a Slab Jamming in the Mantle Transition Zone

Terra Nova, EarlyView.
ABSTRACT Two giant porphyry copper deposits in the Southern Central Andes formed during the Miocene–Pliocene transition when a bend in the subducting Juan de Fernández hotspot chain jammed in the mantle transition zone, causing mega‐scale slab‐kinking. This geometry implies mechanical resistance that caused East–West compression and eventually a thrust‐
Nipaporn Nakrong, Marnie Forster, Wim Spakman, Hielke Jelsma, Francois Gaboury, Gordon Lister   +5 more
wiley   +1 more source

Ophiolites in the Central Asian Orogenic Belt record Cambrian subduction initiation processes

Communications Earth & Environment
Subduction initiation remains elusive because no present example exists. Ophiolites formed over nascent subduction zones in the past provide the key to constraining the processes of subduction initiation.
Mingshuai Zhu, Daniel Pastor–Galán, Matthijs A. Smit, Laicheng Miao, Miao Dong, Fuqin Zhang, Dorjgochoo Sanchir, Ariuntsetseg Ganbat, Chenghao Liu, Ye Luo, Shun Li   +10 more
doaj   +1 more source