Improving global paleogeography since the late Paleozoic using paleobiology

Author List: Wenchao Cao, Sabin Zahirovic, Nicolas Flament, Simon Williams, Jan Golonka, Dietmar Müller Citation: Cao, W., Zahirovic, S., Flament, N., Williams, S., Golonka, J., and Müller, R. D., 2017, Improving global paleogeography since the late Paleozoic using paleobiology: Biogeosciences, v. 14, no. 23, p. 5425-5439. Paleogeographic maps, linked to plate tectonic reconstructions, are key components required for climate models … Read more…

Kinematic constraints on the Rodinia to Gondwana transition

Author List: Andrew Merdith, Simon Williams, Dietmar Müller & Alan Collins. Citation: Merdith, Andrew & Williams, Simon & Müller, Dietmar & Collins, Alan. (2017). Kinematic constraints on the Rodinia-Gondwana transition. Precambrian Research. 299. . 10.1016/j.precamres.2017.07.013. Abstract: Earth’s plate tectonic history during the breakup of the supercontinent Pangea is well constrained from the seafloor spreading record, but evolving plate configurations during … Read more…

Tectonic speed limits from plate kinematic reconstructions

Abstract The motion of plates and continents on the planet’s surface are a manifestation of long-term mantle convection and plate tectonics. Present-day plate velocities provide a snapshot of this ongoing process, and have been used to infer controlling factors on the speeds of plates and continents. However, present-day velocities do not capture plate behaviour over … Read more…

The deep Earth origin of the Iceland plume and its effects on regional surface uplift and subsidence

Abstract The present-day seismic structure of the mantle under the North Atlantic Ocean indicates that the Iceland hotspot represents the surface expression of a deep mantle plume, which is thought to have erupted in the North Atlantic domain during the Palaeocene. The spatial and temporal evolution of the plume since its eruption is still highly … Read more…

A full-plate global reconstruction of the Neoproterozoic

Author List:  Andrew Merdith, Alan Collins, Simon Williams, Sergei Pisarevsky, John Foden, Donnelly Archibald, Morgan Blades, Brandon Alessio, Sheree Armistead, Diana Plavsa, Chris Clark, Dietmar Müller Citation: Merdith, Andrew & Collins, Alan & Williams, Simon & Pisarevsky, Sergei & Foden, John & Archibald, Donnelly & Blades, Morgan & Alessio, Brandon & Armistead, Sheree & Plavsa, Diana & Clark, Chris … Read more…

A Paleomagnetic Database for GPlates: PaleoPoles, Declination Arrows, and PaleoLatitudes

A PaleomagneticPmag Tutorial Image Database that has been assembled for use with the program, GPlates.  The paleomagnetic database presented here is made up of 1638 paleopoles compiled by Rob Van der Voo for his book, Paleomagnetism of the Atlantic, Tethys, and Iapetus Oceans.  In addition to the spreadsheet of paleopoles, we have constructed five feature collections that can be used to visualize the paleomagnetic data using GPlates:  1) site localities, 2) paleopoles, 3) declination arrows, 4) paleolatitude labels, and a set of time-dependent rasters which plot the site locations, paleopoles, declination arrows, and paleolatitude labels on a set of plate tectonic reconstructions ( 0 – 540 Ma).  The last section of this report is a detailed discussion of the paleomagnetic data for three-time intervals (40Ma, 285Ma, and 450Ma).  The Supplementary Materials includes a program, “PaleoPolePlotter”, which GPlates users can use to build paleopoles, declination arrows, and paleolatitude labels from user-defined data sets
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GPlates 2.0 Released

2016_11_MedMeet-Group.jpgGPlates 2.0 was released last week, with lots of new features including plate deformation, volume rendering, much improved project and session management, a plate topology building tool and an interactive tool to determine best-fit rotation poles using the method of Hellinger, and much more. Check out the full list of improvements here. … Read more…

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GPlates 2.0 software and data sets

GPlates 1.5 PromoGPlates is a free desktop software for the interactive visualisation of plate-tectonics. The compilation and documentation of GPlates 2.0 data was primarily funded by AuScope National Collaborative Research Infrastructure (NCRIS).

GPlates is developed by an international team of scientists and professional software developers at the EarthByte Project (part of AuScope) at the University of Sydney, the Division of Geological and Planetary Sciences (GPS) at CalTech, the Geodynamics team at the Geological Survey of Norway (NGU) and the Centre for Earth Evolution and Dynamics (CEED) at the University of Oslo.  … Read more…

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Setting up environment for DCO Demo Analysis

Mac Environment 1.1) Install Anaconda Navigate to the continuum website and download the python 2.7 Mac version of Anaconda, if not already installed. In terminal, where the downloaded anaconda source code is stored, type: bash Anaconda2-4.1.1-MacOSX-x86_64.sh Select yes to all of the prompts. Edit your .bash_profile to include the anaconda bin path in the PATH … Read more…

Ocean Basin Evolution and Global-Scale Plate Reorganization Events Since Pangea Breakup

Author List: Dietmar Müller, Maria Seton, Sabin Zahirovic, Simon Williams, Kara Matthews, Nicky Wright, Grace Shephard, Kayla Maloney, Nicholas Barnett-Moore, Maral Hosseinpour, Dan Bower and John Cannon. Citation: Müller, R.D., Seton, M., Zahirovic, S., Williams, S.E., Matthews, K.J., Wright, N.M., Shephard, G.E., Maloney, K.T., Barnett-Moore, N., Hosseinpour, M., Bower, D.J., & Cannon, J. (2016). Ocean Basin Evolution and … Read more…

Workflow explained: The interaction of subduction zone volcanism with carbonate platforms and continents

Objectives Our two objectives of analysis were to (a) quantify the km-long length areas of interaction of subduction zone volcanism with carbonate platforms and (b) characterise the subduction volcanism as either continental or intra-oceanic depending on the proximity of the subduction zones to continent-ocean boundaries. In regards to the first objective, we are interested in cases where subduction-related … Read more…

PALEOMAP PaleoAtlas for GPlates

PaleoAtlas_imageThe PALEOMAP PaleoAtlas for GPlates consists of 91 paleogeographic maps spanning the Phanerozoic and late Neoproterozoic. The PaleoAtlas can be directly loaded into GPlates as a Time Dependent Raster file. The paleogeographic maps in the PaleoAtlas illustrate the ancient configuration of the ocean basins and continents, as well as important topographic and bathymetric features such as mountains, lowlands, shallow sea, continental shelves, and deep oceans. This tutorial also describes how the maps in the PaleoAtlas were made, documents the sources of information used to make the paleogeographic maps, and provides instructions how to plot user-defined paleodata on the paleogeographic maps using the program PaleoDataPlotter. Read more…

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Ocean basin evolution and global-scale plate reorganization events since Pangea breakup

Seafloor ages from Müller et al.

Seafloor ages from Müller et al.Citation
Müller R.D., Seton, M., Zahirovic, S., Williams, S.E., Matthews, K.J., Wright, N.M., Shephard, G.E., Maloney, K.T., Barnett-Moore, N., Hosseinpour, M., Bower, D.J., Cannon, J., 2016. Ocean basin evolution and global-scale plate reorganization events since Pangea breakup, Annual Review of Earth and Planetary Sciences, Vol 44, 107-138. DOI: 10.1146/annurev-earth-060115-012211.

Abstract
We present a revised global plate motion model with continuously closing plate boundaries ranging from the Triassic at 230 Ma to the present day, assess differences between alternative absolute plate motion models, and review global tectonic events. Relatively high mean absolute plate motion rates around 9–10 cm yr-1 between 140 and 120 Ma may be related to transient plate motion accelerations driven by the successive emplacement of a sequence of large igneous provinces during that time. … Read more…

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Seafloor lithology of the ocean basins

Lithology globe Aus Ant view

Lithology globe Aus Ant viewCitation
Dutkiewicz, A., Müller, R. D., O’Callaghan, S., & Jónasson, H. (2015). Census of seafloor sediments in the world’s ocean. Geology, G36883-1. doi: 10.1130/G36883.1.

Abstract
Knowing the patterns of distribution of sediments in the global ocean is critical for understanding biogeochemical cycles and how deep-sea deposits respond to environmental change at the sea surface. We present the first digital map of seafloor lithologies based on descriptions of nearly 14,500 samples from original cruise reports, interpolated using a support vector machine algorithm. We show that sediment distribution is more complex, with significant deviations from earlier hand-drawn maps, and that major lithologies occur in drastically different proportions globally. … Read more…

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Influence of subduction history on South American topography

Case 4 paleotopography 16MaCitation
Flament, N., Gurnis, M., Müller, R. D., Bower, D. J., & Husson, L. (2015). Influence of subduction history on South American topography. Earth and Planetary Science Letters, 430, 9-18. doi: 10.1016/j.epsl.2015.08.006.

Abstract
The Cenozoic evolution of South American topography is marked by episodes of large-scale uplift and subsidence not readily explained by lithospheric deformation. The drying up of the inland Pebas system, the drainage reversal of the Amazon river, the uplift of the Sierras Pampeanas and the uplift of Patagonia have all been linked to the evolution of mantle flow since the Miocene in separate studies. Here we investigate the evolution of long-wavelength South American topography as a function of subduction history in a time-dependent global geodynamic model. This model is shown to be consistent with these inferred changes, as well as with the migration of the Chaco foreland basin depocentre, that we partly attribute to the inboard migration of subduction resulting from Andean mountain building. … Read more…

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Evaluating global paleoshoreline models for the Cretaceous and Cenozoic

Early CretaceousCitation
Heine, C., Yeo, L. G., & Müller, R. D. (2015). Evaluating global paleoshoreline models for the Cretaceous and Cenozoic. Australian Journal of Earth Sciences, (ahead-of-print), 1-13., doi: 10.1080/08120099.2015.1018321.

Summary
Paleoshoreline maps represent the distribution of land and sea through geologic time. These compilations provide excellent proxies for evaluating the contributions non-tectonic vertical crustal motions, such as mantle convection-driven dynamic topography, to the flooding histories of continental platforms. Until now, such data have not been available as a globally coherent compilation. Here, we present and evaluate a set of Cretaceous and Cenozoic global shoreline data extracted from two independent published global paleogeographic atlases. … Read more…

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A tectonic model reconciling evidence for the collisions between India, Eurasia and intra-oceanic arcs of the central-eastern Tethys

Gibbons etal AgeGrid Vels MagPicks v3 0175Citation
Gibbons, A., Zahirovic, S., Muller, R.D., Whittaker, J., and Yatheesh, V. 2015. A tectonic model reconciling evidence for the collisions between India, Eurasia and intra-oceanic arcs of the central-eastern Tethys. Gondwana Research FOCUS, doi: 10.1016/j.gr.2015.01.001.

Summary
Despite several decades of investigations, inferences on the timing and nature of collisions along the Mesozoic–Cenozoic Eurasian margin remain controversial. We assimilate geological and geophysical evidence into a plate tectonic model for the India–Eurasia collision that includes continuously– … Read more…

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GPlates 1.5 software and data sets

GPlates 1.5 Promo

GPlates 1.5 PromoGPlates is a free desktop software for the interactive visualisation of plate-tectonics. The compilation and documentation of GPlates 1.5 data was primarily funded by AuScope National Collaborative Research Infrastructure (NCRIS).

GPlates is developed by an international team of scientists and professional software developers at the EarthByte Project (part of AuScope) at the University of Sydney, the Division of Geological and Planetary Sciences (GPS) at CalTech, the Geodynamics team at the Geological Survey of Norway (NGU) and the Centre for Earth Evolution and Dynamics (CEED) at the University of Oslo.  … Read more…

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Age, spreading rates and spreading asymmetry of the world’s ocean crust

agegrid_ageerror_2008 rategrid_asymgrid_2008We present four companion digital models of the age, age uncertainty, spreading rates and spreading asymmetries of the world’s ocean basins as geographic and Mercator grids with 2 minute resolution. The grids include data from all the major ocean basins as well as detailed reconstructions of back-arc basins.

The age, spreading rate and asymmetry at each grid node is determined by linear interpolation between adjacent seafloor isochrons in the direction of spreading. Ages for ocean floor between the oldest identified magnetic anomalies and continental crust are interpolated by geological estimates of the ages of passive continental margin segments. … Read more…

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Supplementary resources for "Absolute plate motions since 130 Ma constrained by subduction zone kinematics"

Williams et al 2015 figure 3Citation
Williams, S., Flament, N., Müller, R. D., & Butterworth, N. (2015). Absolute plate motions since 130 Ma constrained by subduction zone kinematics. Earth and Planetary Science Letters, 418, 66-77. doi:10.1016/j.epsl.2015.02.026.

Summary
The supplementary data set comprise plate reconstructions from 130 Ma to present-day, designed to be used within the open-source reconstruction software GPlates.

There are eight sets of reconstructions. In each case, the relative plate motion (RPM) model is unchanged; the differences lie in the absolute plate motion (APM) model. This is expressed in the rotation file as the finite poles of rotation that describe motion of Africa relative to the Earth’s spin-axis. These files were the basis of the results presented in the EPSL paper.  … Read more…

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Supplementary resources for “Absolute plate motions since 130 Ma constrained by subduction zone kinematics”

Williams et al 2015 figure 3Citation
Williams, S., Flament, N., Müller, R. D., & Butterworth, N. (2015). Absolute plate motions since 130 Ma constrained by subduction zone kinematics. Earth and Planetary Science Letters, 418, 66-77. doi:10.1016/j.epsl.2015.02.026.

Summary
The supplementary data set comprise plate reconstructions from 130 Ma to present-day, designed to be used within the open-source reconstruction software GPlates.

There are eight sets of reconstructions. In each case, the relative plate motion (RPM) model is unchanged; the differences lie in the absolute plate motion (APM) model. This is expressed in the rotation file as the finite poles of rotation that describe motion of Africa relative to the Earth’s spin-axis. These files were the basis of the results presented in the EPSL paper.  … Read more…

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Experimental release of GPlates 1.5+Hellinger

GPlates 1.5 Promo

An experimental release of GPlates 1.5+Hellinger was released this week. This version includes all GPlates 1.5 functionality as well as a Hellinger Tool to calculate best-fitting poles to segmented magnetic pick data points. The tool uses a Python implementation of the FORTRAN program by Chang and others and is compatible with FORTRAN data files which can … Read more…

GPlates Portal

Lithology globe Aus Ant view

Lithology globe Aus Ant viewThe GPlates Portal is a free and interactive cloud-based tool that enables the visualisation of cutting-edge geoscience datasets. Using a published plate kinematic model, datasets can be reconstructed back through time to the Jurassic, 200 million years ago.

Currently, global satellite-derived vertical gravity gradient data can be visualised via the Portal, and global maps of free-air gravity anomalies and magnetic anomalies can be tectonically reconstructed.

The GPlates Portal is also the gateway to the Paleomap Maker, a web service designed to provide researchers with plate-tectonic data reconstruction and visualization services. The core reconstruction engine is powered by the cutting-edge open-source plate-tectonic reconstruction software, GPlates, and the visualization is made available by using Matplotlib Basemap Toolkit. … Read more…

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New GPlates Portal available

GPlates Portal Figure

EarthByte have launched a new cloud-based GPlates Web Portal that was used by almost 40 000 users over the last long-weekend! It took GPlates software over ten years to get that many users, so this is a huge achievement and also makes GPlates accessible to a broader audience! The GPlates portal can be used to … Read more…

Post-Jurassic tectonic evolution of southeast Asia from Zahirovic et al. (2014)

Asia Zahirovic 20maCitation
Zahirovic, S., Seton, M., and Müller, R. D., (2014). The Cretaceous and Cenozoic tectonic evolution of Southeast Asia: Solid Earth (EGU).

Summary
Tectonic reconstructions of Southeast Asia have given rise to numerous controversies that include the accretionary history of Sundaland and the enigmatic tectonic origin of the Proto South China Sea. We assimilate a diversity of geological and geophysical observations into a new regional plate model, coupled to a global model, to address these debates.

Our approach takes into account terrane suturing and accretion histories, the location of subducted slabs imaged in mantle tomography in order to constrain the evolution of regional subduction zones, as well as plausible absolute and relative plate velocities and tectonic driving mechanisms. … Read more…

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The tectonic stress field evolution of India since the Oligocene

Muller etal India Paleostress Graphical AbstractCitation
Müller, R. D., Yatheesh, V., & Shuhail, M. (2014). The tectonic stress field evolution of India since the Oligocene. Gondwana Research.

Summary
We use a 2 dimensional finite element model with heterogeneous elastic strengths in continental areas to model the regional stress field orientation and relative magnitudes in and around India for 33 Ma, 20 Ma and the present day. The large-scale geological structure of India is embedded in our model by using published outlines of cratons, fold belts and basins, associated with estimates of their relative strengths, enabling the modelling of stress field deflections along interfaces between relatively strong and weak tectonic elements through time. … Read more…

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GPlates 1.4 now available to download

GPlates Version 1.4 has been released! This latest update of GPlates brings added functionality for the export of both numerical floating point-data and colour reconstructed rasters, for a user specified region and resolution. There is also greater flexibility for raster file import, with ERMapper, Erdas Imagine and GeoTIFF files now supported and geo-referencing is retained … Read more…

Topographic asymmetry of the South Atlantic from global models of mantle flow and lithospheric stretching

Flament et al EPSL 2014 - FigureCitation
Flament, N., Gurnis, M., Williams, S., Seton, M., Skogseid, J., Heine, C., & Müller, R. D. (2014). Topographic asymmetry of the South Atlantic from global models of mantle flow and lithospheric stretching. Earth and Planetary Science Letters, 387, 107-119. dx.doi.org/10.1016/j.epsl.2013.11.017.

Abstract
The relief of the South Atlantic is characterized by elevated passive continental margins along southern Africa and eastern Brazil, and by the bathymetric asymmetry of the southern oceanic basin where the western flank is much deeper than the eastern flank. We investigate the origin of these topographic features in the present and over time since the Jurassic with a model of global mantle flow and lithospheric deformation. The model progressively assimilates plate kinematics, plate boundaries and lithospheric age derived from global tectonic reconstructions with deforming plates, and predicts the evolution of mantle temperature, continental crustal thickness, long-wavelength dynamic topography, and isostatic topography. … Read more…

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The breakup of east Gondwana: assimilating constraints from Cretaceous ocean basins around India into a best-fit tectonic model, Gibbons et al. (2013)

Citation
Gibbons, A., Whittaker, J. and R. Dietmar Müller, (2013), The break up of East Gondwana: assimilating constraints from Cretaceous ocean basins around India into a best-fit tectonic model. Journal of Geophysical Research, 118, 1-15: doi:10.1002/jgrb.50079

East GondwanaSummary
Published models for the Cretaceous seafloor-spreading history of East Gondwana result in unlikely tectonic scenarios for at least one of the plate boundaries involved and/or violate particular constraints from at least one of the associated ocean basins. We link East Gondwana spreading corridors by integrating magnetic and gravity anomaly data from the Enderby Basin off East Antarctica within a regional plate kinematic framework to identify a conjugate series of east-west-trending magnetic anomalies, M4 to M0 (~126.7–120.4 Ma). … Read more…

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A review of observations and models of dynamic topography

Citation
Flament, N., Gurnis, M., & Müller, R. D. (2013). A review of observations and models of dynamic topography. Lithosphere, 5(2), 189-210. doi: 10.1130/L245.1

Flament-et-al_fig1Summary
The topography of Earth is primarily controlled by lateral differences in the density structure of the crust and lithosphere. In addition to this isostatic topography, flow in the mantle induces deformation of its surface leading to dynamic topography. This transient deformation evolves over tens of millions of years, occurs at long wavelength, and is relatively small (<2 km) in amplitude. Here, we review the observational constraints and modeling approaches used to understand the amplitude, spatial pattern, and time dependence of dynamic topography. … Read more…

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