Insights on the kinematics of the India-Eurasia collision from global geodynamic models

Image 002We present the input plate motion models and results from the study by Zahirovic et al. (2012) on the India-Eurasia collision using linked kinematic and geodynamic models.

Two end-member scenarios of the India-Eurasia collision were tested. The conventional model invokes long-lived Andean-style subduction along southern Eurasia until continental collision between a maximum extent Greater India and Lhasa at ~60 Ma. … Read more…

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Full-fit, palinspastic reconstruction of the conjugate Australian-Antarctic margins

AusAntCThick47Ma-1Despite decades of study the pre-rift configuration and early rifting history between Australia and Antarctica is not well established. The plate boundary system during the Cretaceous includes the evolving Kerguelen-Broken Ridge Large Igneous Province in the west as well as the conjugate passive and transform margin segments of the Australian and Antarctic continents. … Read more…

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Dynamic subsidence of eastern Australia during the Cretaceous

Dynamic Subsidence of Eastern Australia Matthews et al (2011)During the Early Cretaceous Australia’s eastward passage over sinking subducted slabs induced widespread dynamic subsidence and formation of a large eperiogenic sea in the eastern interior. Despite evidence for convergence between Australia and the paleo-Pacific, the subduction zone location has been poorly constrained. Using coupled plate tectonic-mantle convection models, we test two end-member scenarios, one with subduction directly east of Australia’s reconstructed continental margin, and a second with subduction translated ~1000 km east, implying the existence of a back-arc basin. Our models incorporate a rheological model for the mantle and lithosphere, plate motions since 140 Ma and evolving plate boundaries. While mantle rheology affects the magnitude of surface vertical motions, timing of uplift and subsidence depends on plate boundary geometries and kinematics. … Read more…

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How supercontinents and superoceans affect seafloor roughness

Tasman Sea grav SW Indian grav Pacific grav

Seafloor roughness varies considerably across the world’s ocean basins and is fundamental to controlling the circulation and mixing of heat in the ocean and dissipating eddy kinetic energy. Models derived from analyses of active mid-ocean ridges suggest that ocean floor roughness depends on seafloor spreading rates, with rougher basement forming below a half-spreading rate threshold of 30-35 mm/yr, as well as on the local interaction of mid-ocean ridges with mantle plumes or cold-spots.
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Age and Bathymetry of the World’s Ocean Crust for the last 140 million years

Muller etal Figure1Reconstructing vanished oceans
We establish the locations and geometry of mid ocean ridges through time on the basis of marine magnetic anomaly identifications, geological information such as paleomagnetic data from terranes and microcontinents, especially in the Tethys Ocean, mid-oceanic ridge subduction events and the rules of plate tectonics. Based on a global set of tectonic plate rotations we construct a set of refined seafloor isochrons following the interpolation technique outlined by Müller et al. (1997; 2008) but including a multitude of additional data. … Read more…

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Herold et al. 2008 Mid Miocene topographic/bathymetric dataset

Citation: Herold, N., Seton, M., Muller, R.D., You, Y. and Huber, M. (2008). Middle Miocene tectonic boundary conditions for use in climate models. Geochemisty Geophysics Geosystems, 9, Q10009. doi:10.1029/2008GC002046. Abstract: Utilizing general circulation models (GCMs) for paleoclimate study requires the construction of appropriate model boundary conditions. We present a middle Miocene paleotopographic and paleobathymetric reconstruction … Read more…

Global subduction and back-arc basin grids and data

Please Note: These age grids are now outdated. Please see the agegrids available from the Müller et al. 2013 study on Ocean Chemistry at the Seawater chemistry driven by supercontinent assembly, break-up and dispersal resource page.

Subduction image 1Downloads
Download global subduction age grid images via FTP here – tgz file
Download global subduction parameter dataset via FTP here – tgz file
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Ellipsis

Ellipsis Visual Editor screenshotEllipsis is a lagrangian particle-in-cell finite element modelling software tool with an associated graphical user interface (GUI). Ellipsis, along with its GUI and its associated documentation allow novice users to assemble 2D or 3D numerical experiment for lithospheric extension and/or compression over a convecting mantle or simply run a mantle convection experiment with or without continents in a relatively short time, including the scaling of relevant parameters.  … Read more…

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Generic Mapping Tools (GMT)

GMT is an open source collection of about 80 command-line tools for manipulating geographic and Cartesian data sets (including filtering, trend fitting, gridding, projecting, etc.) and producing PostScript illustrations ranging from simple x–y plots via contour maps to artificially illuminated surfaces and 3D perspective views; the GMT supplements add another 40 more specialized and discipline-specific … Read more…