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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Badlands v2.0 is released

Today version 2.0 of Badlands has been released This release add new capabilities to the code: simulates river entering in the simulation area output of Chi parameter in Hdf5 flow network multi-erodibility layers creation 3D stratigraphic layer displacements This release is compatible with version 1.0.0 and will work with similar XML input files. Download Badlands (source … Read more…

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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SoftwareX – Badlands: A parallel basin and landscape dynamics model

Abstract: Over more than three decades, a number of numerical landscape evolution models (LEMs) have been developed to study the combined effects of climate, sea-level, tectonics and sediments on Earth surface dynamics. Most of them are written in efficient programming languages, but often cannot be used on parallel architectures. Here, I present a LEM which … Read more…

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…

Workflow explained: Measuring global subduction zone lengths with pyGPlates

For our first analysis, we developed a simple work flow to quantify subduction zone lengths from 0 to 400 Ma, using the Matthews et al. (2016) plate kinematic model. The bash workflow consists of python scripts, GMT tools and AWK scripts organised into bash sub-routine functions. The most integral parts of the workflow are the python scripts … 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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Computers & Geosciences – Badlands: An open-source, flexible and parallel framework to study landscape dynamics

Salles, T., and Hardiman, L. (2016). Badlands: An open-source, flexible and parallel framework to study landscape dynamics. Computers & Geosciences 91 77–89. DOI: 10.1016/j.cageo.2016.03.011 Badlands: An open-source, flexible and parallel framework to study landscape dynamics

Computers & Geosciences – Badlands: An open-source, flexible and parallel framework to study landscape dynamics

Author List: Tristan Salles, Luke Hardiman Citation: Salles, T., and Hardiman, L. (2016). Badlands: An open-source, flexible and parallel framework to study landscape dynamics. Computers & Geosciences 91 77–89. DOI: 10.1016/j.cageo.2016.03.011 Abstract: In this paper, we propose a minimal numerical model which governing equations describe the following processes: erosion, sedimentation, diffusion and flexure. The model respects conservation … Read more…

pygplates beta revision 12 released

GPlates Vector Logo

GPlates Vector LogoThe first beta release of pygplates (the GPlates Python library) is now available for download.

pygplates enables access to GPlates functionality via the Python programming language. This may be of particular use to researchers requiring more flexibility than is provided by the GPlates user interface.

The following pygplates functionality is available:-

  • Load and save feature data (GPML, Shapefile, etc)
  • Create/modify/query feature data
  • Traverse/modify/query plate rotation hierarchy
  • Partition into plates and assign plate properties
  • Reconstruct geometries, flowlines, motion paths
  • Resolve topological plates and query their boundary sections (ridges/subductions)
  • Calculate velocities
  • Distance between geometries (region-of-interest queries)
  • Geometry queries (length, point-in-polygon, area, centroid, tessellate, interpolate, join, partition)

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Data Processing and Plotting Using 
Generic Mapping Tools (GMT) Course

GMT Course Image 2016

GMT Course Image 2016Course Overview
This course is designed to introduce students to different types of spatial data, data processing and interpolation functions and data plotting using GMT (Generic Mapping Tools). GMT is a set of public domain tools that will be used in conjunction with UNIX general processing tools (awk, grep) and basic shell programming. The examples presented in the course will focus on marine geophysical data, however many of the principles are applicable to other scientific data.

The learning outcomes for the course include:  … 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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Basin and Landscape Dynamics (Badlands)

Badlands image

Basin and Landscape Dynamics (Badlands) is a parallel TIN-based landscape evolution model, built to simulate topography development at various space and time scales. The model is capable of simulating hillslope processes, fluvial incision (erosion/transport/deposition), spatially and temporally varying geodynamic (3D displacements) and climatic forces which can be used to simulate changes in base level, as … Read more…

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…