scholarly journals Backarc lithospheric thickness and serpentine stability control slab‐mantle coupling depths in subduction zones

2021 ◽  
Author(s):  
Buchanan C. Kerswell ◽  
Matthew J. Kohn ◽  
Taras V. Gerya
Keyword(s):  
Subduction Zones ◽  
Stability Control ◽  
Lithospheric Thickness

scholarly journals When crust comes of age: on the chemical evolution of Archaean, felsic continental crust by crustal drip tectonics

2018 ◽  
Vol 376 (2132) ◽  
pp. 20180103 ◽  
Author(s):  
O. Nebel ◽  
F. A. Capitanio ◽  
J.-F. Moyen ◽  
R. F. Weinberg ◽  
F. Clos ◽  
...  
Keyword(s):  
Subduction Zones ◽  
Plate Tectonics ◽  
Geochemical Data ◽  
Evolutionary Stage ◽  
Secular Evolution ◽  
Lithospheric Thickness ◽  
Asthenospheric Mantle ◽  
Wide Scale ◽  
Granitoid Intrusions ◽  
Lower Crustal

The secular evolution of the Earth's crust is marked by a profound change in average crustal chemistry between 3.2 and 2.5 Ga. A key marker for this change is the transition from Archaean sodic granitoid intrusions of the tonalite–trondhjemite–granodiorite (TTG) series to potassic (K) granitic suites, akin (but not identical) to I-type granites that today are associated with subduction zones. It remains poorly constrained as to how and why this change was initiated and if it holds clues about the geodynamic transition from a pre-plate tectonic mode, often referred to as stagnant lid, to mobile plate tectonics. Here, we combine a series of proposed mechanisms for Archaean crustal geodynamics in a single model to explain the observed change in granitoid chemistry. Numeric modelling indicates that upper mantle convection drives crustal flow and subsidence, leading to profound diversity in lithospheric thickness with thin versus thick proto-plates. When convecting asthenospheric mantle interacts with lower lithosphere, scattered crustal drips are created. Under increasing P-T conditions, partial melting of hydrated meta-basalt within these drips produces felsic melts that intrude the overlying crust to form TTG. Dome structures, in which these melts can be preserved, are a positive diapiric expression of these negative drips. Transitional TTG with elevated K mark a second evolutionary stage, and are blends of subsided and remelted older TTG forming K-rich melts and new TTG melts. Ascending TTG-derived melts from asymmetric drips interact with the asthenospheric mantle to form hot, high-Mg sanukitoid. These melts are small in volume, predominantly underplated, and their heat triggered melting of lower crustal successions to form higher-K granites. Importantly, this evolution operates as a disseminated process in space and time over hundreds of millions of years (greater than 200 Ma) in all cratons. This focused ageing of the crust implies that compiled geochemical data can only broadly reflect geodynamic changes on a global or even craton-wide scale. The observed change in crustal chemistry does mark the lead up to but not the initiation of modern-style subduction. This article is part of a discussion meeting issue ‘Earth dynamics and the development of plate tectonics’.

scholarly journals Thickness of the lithosphere beneath Turkey and surroundings from S-receiver functions

Solid Earth ◽  
2015 ◽  
Vol 6 (3) ◽  
pp. 971-984 ◽  
Author(s):  
R. Kind ◽  
T. Eken ◽  
F. Tilmann ◽  
F. Sodoudi ◽  
T. Taymaz ◽  
...  
Keyword(s):  
Subduction Zones ◽  
Receiver Function ◽  
Receiver Functions ◽  
Public Access ◽  
Entire Region ◽  
African Plate ◽  
Lithospheric Thickness ◽  
The North ◽  
Conversion Point ◽  
Surrounding Areas

Abstract. We analyze S-receiver functions to investigate variations of lithospheric thickness below the entire region of Turkey and surrounding areas. The teleseismic data used here have been compiled combining all permanent seismic stations which are open to public access. We obtained almost 12 000 S-receiver function traces characterizing the seismic discontinuities between the Moho and the discontinuity at 410 km depth. Common-conversion-point stacks yield well-constrained images of the Moho and of the lithosphere–asthenosphere boundary (LAB). Results from previous studies suggesting shallow LAB depths between 80 and 100 km are confirmed in the entire region outside the subduction zones. We did not observe changes in LAB depths across the North and East Anatolian faults. To the east of Cyprus, we see indications of the Arabian LAB. The African plate is observed down to about 150 km depth subducting to the north and east between the Aegean and Cyprus with a tear at Cyprus. We also observed the discontinuity at 410 km depth and a negative discontinuity above the 410, which might indicate a zone of partial melt above this discontinuity.

scholarly journals Thickness of the lithosphere beneath Turkey and surroundings from S-receiver functions

2015 ◽  
Vol 7 (2) ◽  
pp. 1315-1346 ◽  
Author(s):  
R. Kind ◽  
T. Eken ◽  
F. Tilmann ◽  
F. Sodoudi ◽  
T. Taymaz ◽  
...  
Keyword(s):  
Subduction Zones ◽  
Receiver Function ◽  
Receiver Functions ◽  
Public Access ◽  
Entire Region ◽  
African Plate ◽  
Lithospheric Thickness ◽  
The North ◽  
Teleseismic Data ◽  
S Receiver Function

Abstract. We analyze S-receiver functions to investigate the variations of lithospheric thickness below the entire region of Turkey and surroundings. The teleseismic data used here have been compiled combining all permanent seismic stations which are open to public access. We obtained almost 12 000 S-receiver function traces characterizing the seismic discontinuities between the Moho and the discontinuity at 410 km depth. Common-conversion-points stacks yield well-constrained images of the Moho and of the lithosphere–asthenosphere boundary (LAB). Results from previous studies suggesting shallow LAB depths between 80 and 100 km are confirmed in the entire region outside the subduction zones. We did not observe changes of LAB depths across the North and East Anatolian Faults. To the east of Cyprus, we see indications of the Arabian LAB. The African plate is observed down to about 150 km depth subducting to the north and east between the Aegean and Cyprus with a tear at Cyprus. We also observed the discontinuity at 410 km depth and a negative discontinuity above the 410, which might indicate a zone of partial melt above this discontinuity.

Petrologic and geochemical role of serpentinite in subduction zones and plate interface domains

2015 ◽  
Vol 37 ◽  
pp. 61-64
Author(s):  
Marco Scambelluri ◽  
Enrico Cannaò ◽  
Mattia Gilio ◽  
Marguerite Godard
Keyword(s):  
Subduction Zones ◽  
Plate Interface

A Study on Zero Assignment by Fault Tolerant Stability Control

2016 ◽  
Vol 136 (2) ◽  
pp. 143-156 ◽  
Author(s):  
Katsuhiko Fuwa ◽  
Tatsuo Narikiyo ◽  
Tatsushi Ooba
Keyword(s):  
Fault Tolerant ◽  
Stability Control

Development of Trunk Transmission Online Integrated Stability Control System (ISC) for New Generation Grid

2017 ◽  
Vol 137 (6) ◽  
pp. 434-445 ◽  
Author(s):  
Hiroshi Yoshida ◽  
Ryuji Tachi ◽  
Koya Takafuji ◽  
Hironori Imaeda ◽  
Masaru Takeishi ◽  
...  
Keyword(s):  
Control System ◽  
Stability Control ◽  
Stability Control System ◽  
New Generation
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