The effects of ridge subduction on the thermal structure of accretionary prisms: A Tertiary example from the Shimanto Belt of Japan

1993 ◽  
pp. 151-168 ◽  
Author(s):  
Michael B. Underwood ◽  
Tim Byrne ◽  
J. P. Hibbard ◽  
Lee DiTullio ◽  
Matthew M. Laughland
Keyword(s):  
Thermal Structure ◽  
Ridge Subduction ◽  
Shimanto Belt ◽  
Accretionary Prisms

scholarly journals Advances in the thermal and petrologic modeling of subduction zones

Geosphere ◽  
2020 ◽  
Vol 16 (4) ◽  
pp. 936-952 ◽  
Author(s):  
Simon M. Peacock
Keyword(s):  
Heat Flux ◽  
Subduction Zones ◽  
Mantle Wedge ◽  
Dynamic Models ◽  
Seismic Velocity ◽  
Thermal Structure ◽  
Metamorphic Rocks ◽  
Ridge Subduction ◽  
Dehydration Reactions ◽  
Flux Measurements

Abstract In the two decades since Subduction: Top to Bottom was published in 1996, improved analytical and numerical thermal-petrologic models of subduction zones have been constructed and evaluated against new seismological and geological observations. Advances in thermal modeling include a range of new approaches to incorporating shear (frictional, viscous) heating along the subduction interface and to simulating induced flow in the mantle wedge. Forearc heat-flux measurements constrain the apparent coefficient of friction (μ′) along the plate interface to <∼0.1, but the extent to which μ′ may vary between subduction zones remains challenging to discern owing to scatter in the heat-flux measurements and uncertainties in the magnitude and distribution of radiogenic heat production in the overriding crust. Flow in the mantle wedge and the resulting thermal structure depend on the rheology of variably hydrated mantle rocks and the depth at which the subducting slab becomes coupled to the overlying mantle wedge. Advances in petrologic modeling include the incorporation of sophisticated thermodynamic software packages into thermal models and the prediction of seismic velocities from mineralogic and petrologic models. Current thermal-petrologic models show very good agreement between the predicted location of metamorphic dehydration reactions and observed intermediate-depth earthquakes, and between the predicted location of the basalt-to-eclogite transition in subducting oceanic crust and observed landward-dipping, low-seismic-velocity layers. Exhumed high-pressure, low-temperature metamorphic rocks provide insight into subduction-zone temperatures, but important thermal parameters (e.g., convergence rate) are not well constrained, and metamorphic rocks exposed at the surface today may reflect relatively warm conditions in the past associated with subduction initiation or ridge subduction. We can anticipate additional advances in our understanding of subduction zones as a result of further testing of model predictions against geologic and geophysical observations, and of evaluating the importance of advective processes, such as diapirism and subduction-channel flow, that are not captured in hybrid kinematic-dynamic models of subduction zones but are observed in fully dynamical models under certain conditions.

scholarly journals Fluid circulation in the depths of accretionary prisms: an example of the Shimanto Belt, Kyushu, Japan

2015 ◽  
Vol 655 ◽  
pp. 161-176 ◽  
Author(s):  
Hugues Raimbourg ◽  
Maxime Vacelet ◽  
Claire Ramboz ◽  
Vincent Famin ◽  
Romain Augier ◽  
...  
Keyword(s):  
Fluid Circulation ◽  
Shimanto Belt ◽  
Accretionary Prisms
Sign in / Sign up

Export Citation Format

Share Document