Dynamic topography of passive continental margins and their hinterlands since the Cretaceous

Even though it is well accepted that the Earth’s surface topography has been affected by mantle-convection induced dynamic topography, its magnitude and time-dependence remain controversial.  The dynamic influence to topographic change along continental margins is particularly difficult to unravel, because their stratigraphic record is dominated by tectonic subsidence caused by rifting. We follow a three-fold … Read more…

A full-plate global reconstruction of the Neoproterozoic

Abstract Neoproterozoic tectonic geography was dominated by the formation of the supercontinent Rodinia, its break-up and the subsequent amalgamation of Gondwana. The Neoproterozoic was a tumultuous time of Earth history, with large climatic variations, the emergence of complex life and a series of continent-building orogenies of a scale not repeated until the Cenozoic. Here we … 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…

Origin and evolution of the deep thermochemical structure beneath Eurasia

Flament_Figure5Citation

Flament, N. et al. Origin and evolution of the deep thermochemical structure beneath Eurasia. Nat. Commun. 7, 14164 doi: 10.1038/ncomms14164 (2016).

Abstract 

A unique structure in the Earth’s lowermost mantle, the Perm Anomaly, was recently identified beneath Eurasia. It seismologically resembles the large low-shear velocity provinces (LLSVPs) under Africa and the Pacific, but is much smaller. This challenges the current understanding of the evolution of the plate–mantle system in which plumes rise from the edges of the two LLSVPs, spatially fixed in time. New models of mantle flow over the last 230 million years reproduce the present-day structure of the lower mantle, and show a Perm-like anomaly. The anomaly formed in isolation within a closed subduction network ~22,000 km in circumference before 150 million years ago before migrating ~1,500 km westward at an average rate of 1 cm per year, indicating a greater mobility of deep mantle structures than previously recognized. We hypothesize that the mobile Perm Anomaly could be linked to the Emeishan volcanics, in contrast to the previously proposed Siberian Traps. 

This article is freely accessible using the following link http://rdcu.be/oDqg Read more…

Global plate boundary evolution and kinematics since the late Paleozoic

Matthews++_SummaryFigCitation

Matthews, K.J., Maloney, K.T., Zahirovic, S., Williams, S.E., Seton, M., and Müller, R.D. (2016). Global plate boundary evolution and kinematics since the late Paleozoic, Global and Planetary Change, 146, 226-250. DOI: 10.1016/j.gloplacha.2016.10.002

Abstract

Many aspects of deep-time Earth System models, including mantle convection, paleoclimatology, paleobiogeography and the deep Earth carbon cycle, require high-resolution plate models that include the evolution of the mosaic of plate boundaries through time. We present the first continuous late Paleozoic to present-day global plate model with evolving plate boundaries, building on and extending two previously published models for the late Paleozoic (410–250 Ma) and Mesozoic-Cenozoic (230–0 Ma). We ensure continuity during the 250–230 Ma transition period between the two models, update the absolute reference frame of the Mesozoic-Cenozoic model and add a new Paleozoic reconstruction for the Baltica-derived Alexander Terrane, now accreted to western North America. This 410–0 Ma open access model provides a framework for deep-time whole Earth modelling and acts as a base for future extensions and refinement.

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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…

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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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 Reviews of Earth and Planetary Sciences, in press.

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…

Prospectivity of Western Australian iron ore from geophysical data using a reject option classifier

Prospectivity of Western Australian iron ore from geophysical data using a reject option classifier - figure

Prospectivity of Western Australian iron ore from geophysical data using a reject option classifier - figureCitation
Merdith, A. S., Landgrebe, T. C., & Müller, R. D. (2015). Prospectivity of Western Australian iron ore from geophysical data using a reject option classifier. Ore Geology Reviews. http://dx.doi.org/10.1016/j.oregeorev.2015.03.014

Abstract
There has recently been a rapid growth in the amount and quality of digital geological and geophysical data for the majority of the Australian continent. Coupled with an increase in computational power and the rising impor- tance of computational methods, there are new possibilities for a large scale, low expenditure digital exploration of mineral deposits. Here we use a multivariate analysis of geophysical datasets to develop a methodology that utilises machine learning algorithms to build and train two-class classifiers for provincial-scale, greenfield min- eral exploration. … Read more…

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…

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…

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…

Long-term interaction between mid-ocean ridges and mantle plumes

Whittaker et al 2015 MORs plumes LIPSCitation
Whittaker, J. M., Afonso, J. C., Masterton, S., Müller, R. D., Wessel, P., Williams, S. E., & Seton, M. (2015). Long-term interaction between mid-ocean ridges and mantle plumes. Nature Geoscience, 8(6), 479-483.

Summary
Plate tectonic motions are commonly considered to be driven by slab pull at subduction zones and ridge push at mid-ocean ridges, with motion punctuated by plumes of hot material rising from the lower mantle. Within this model, the geometry and location of mid-ocean ridges are considered to be independent of lower-mantle dynamics, such as deeply sourced plumes that produce voluminous lava eruptions-termed large igneous provinces. Here we use a global plate model to reconstruct the locations of large igneous provinces relative to plumes and mid-ocean ridges at the time they formed. … 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…

Tectonic speed limits from plate kinematic reconstructions

Plate velocities summary figureCitation
Zahirovic, S., Müller, R. D., Seton, M., & Flament, N. (2015). Tectonic speed limits from plate kinematic reconstructions. Earth and Planetary Science Letters, 418, 40-52. doi:10.1016/j.epsl.2015.02.037.

Summary
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 geologically representative periods of time. To address this shortcoming, we use a plate tectonic reconstruction approach to extract time-dependent plate velocities and geometries from which root mean square (RMS) velocities are computed, resulting in a median RMS plate speed of ~4 cm/yr over 200 Myr.  … Read more…

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…

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…

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…

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…

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…

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…

Linking rift propagation barriers to excess magmatism at volcanic rifted margins

Koopmann etal 2014 Model EvolutionCitation
Koopman, H., Brune, S., Franke, D. and Breuer. 2014. Linking rift propagation barriers to excess magmatism at volcanic rifted margins. Geology (Pre-Issue Publication 15. Oct), doi: 10.1130/G36085.

Summary
Break-up–related extrusive magmatism, imaged in reflection seismic data as seaward-dipping reflectors (SDRs), extends sym- metrically along the volcanic margins of the Atlantic Ocean. Recent research found distinct along-margin variations in the distribution of SDRs, and abundance of volcanic material was found to be spatially linked to transfer fault systems. These segmented the propagating rift that later developed into the ocean, and are interpreted as rift propa- gation barriers. Based on these observations, we develop a numeri- cal model, which shows that rift-parallel mantle flow and locally enhanced rates of volcanism are the result of delays in rift propaga- tion and segmented opening. … Read more…

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…

New global marine gravity model, Sandwell et al. (2014)

Indian Ocean View Westward from AustraliaCitation
Sandwell, D. T., Müller, R. D., Smith, W. H. F., Garcia, E. and Francis, R. 2014. New global marine gravity model from Cryo-Sat-2 and jason-1 reveals buried tectonic structure. Science, Vol. 346, 6205, pp. 65-67, doi: 10.1126/science.1258213.

Summary
New global marine gravity model from CryoSat-2 and Jason-1 reveals buried tectonic structure.

View the new gravity map in an online 3D portal!

Gravity models are powerful tools for mapping tectonic structures, especially in the deep ocean basins where the topography remains unmapped by ships or is buried by thick sediment. We combined new radar altimeter measurements from satellites CryoSat-2 and Jason-1 with existing data to construct a global marine gravity model that is two times more accurate than previous models. We found an extinct spreading ridge in the Gulf of Mexico, a … 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…

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…

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…

Geoscientific Model Development – A suite of early Eocene (~55 Ma) climate model boundary conditions

Herold_etal_2014_BIOME4

Herold, N., Buzan, J., Seton, M., Goldner, A., Green, J. A. M., Müller, R. D., Markwick, P., & Huber, M. (2014). A suite of early Eocene (~ 55 Ma) climate model boundary conditions. Geoscientific Model Development, 7(5), 2077-2090. doi: 10.5194/gmd-7-2077-2014.

A suite of early Eocene (~ 55 Ma) climate model boundary conditions

Supplementary data

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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…