EOS: Billion-year rewind tracks supercontinents and mantle structures

AGU Science News: Billion-Year Rewind Tracks Supercontinents and Mantle Structures – EOS has featured our recent paper on tracing past pathways of tectonic plates and their boundaries back a billion years. The article highlights how our work on solid Earth system evolution is driving “a second plate tectonic revolution”., inspiring future work to test and … Read more…

Solid Earth: A tectonic-rules-based mantle reference frame since 1 billion years ago – implications for supercontinent cycles and plate–mantle system evolution

Understanding the long-term evolution of Earth’s plate-mantle system is reliant on absolute plate motion models in a mantle reference frame, but such models are both difficult to construct and controversial. We present a tectonic rules-based optimisation approach to construct a plate motion model in a mantle reference frame covering the last billion years and use … Read more…

EPSL: Long-term Phanerozoic sea level change from solid Earth processes

The sedimentary rock record suggests that global sea levels may have fluctuated by hundreds of meters throughout Phanerozoic times. Long-term (10–80 Myr) sea level change can be inferred from paleogeographic reconstructions and stratigraphic methods can be used to estimate sea level change over 1–10 Myr in tectonically quiescent regions assumed to be stable. Plate tectonic … Read more…

Coupled evolution of plate tectonics and basal mantle structure

The relationships between plate motions and basal mantle structure remain poorly understood, with some models implying that the basal mantle structure has remained stable over time, while others suggest that it could be shaped by the aggregation and dispersal of supercontinents. Here we investigate the evolution of mantle flow driven by end‐member plate tectonic models … Read more…

Reconstructing seafloor age distributions in lost ocean basins

Abstract: Reconstructions of past seafloor age make it possible to quantify how plate tectonic forces, surface heat flow, ocean basin volume and global sea-level have varied through geological time. However, past ocean basins that have now been subducted cannot be uniquely reconstructed, and a significant challenge is how to explore a wide range of possible … Read more…

The interplay of dynamic topography and eustasy on continental flooding in the late Paleozoic

Abstract: Global sea level change can be inferred from sequence stratigraphic and continental flooding data. These methods reconstruct sea level from peri-cratonic and cratonic basins that are assumed to be tectonically stable and sometimes called reference districts, and from spatio-temporal correlations across basins. However, it has been understood that long-wavelength (typically hundreds of km) and low-amplitude … Read more…

Constraining Absolute Plate Motions Since the Triassic

Abstract: The absolute motion of tectonic plates since Pangea can be derived from observations of hotspot trails, paleomagnetism, or seismic tomography. However, fitting observations is typically carried out in isolation without consideration for the fit to unused data or whether the resulting plate motions are geodynamically plausible. Through the joint evaluation of global hotspot track … Read more…

The interplay of dynamic topography and eustasy on continental flooding in the late Paleozoic

Abstract: Global sea level change can be inferred from sequence stratigraphic and continental flooding data. These methods reconstruct sea level from peri-cratonic and cratonic basins that are assumed to be tectonically stable and sometimes called reference districts, and from spatio-temporal correlations across basins. However, it has been understood that long-wavelength (typically hundreds of km) and … Read more…

Geodynamic reconstruction of an accreted Cretaceous back-arc basin in the Northern Andes

Abstract A complex history of subduction, back-arc basin formation, terrane accretion and transpressional shearing characterizes the evolution of the Caribbean and northern South American margin since Jurassic times. Quantitative plate tectonic reconstructions of the area do not include Jurassic-Cretaceous back-arc terranes of which there are both geological and geophysical observations. We developed a revised plate … Read more…

Tectonic evolution and deep mantle structure of the eastern Tethys since the latest Jurassic

Sabin Zahirovic, Kara J. Matthews, Nicolas Flament, R. Dietmar Müller, Kevin C. Hill, Maria Seton, Michael Gurnis Earth-Science Reviews Citation: Zahirovic, S., Matthews, K.J., Flament, N., Müller, R.D., Hill, K.C., Seton, M. and Gurnis, M., 2016, Tectonic evolution and deep mantle structure of the eastern Tethys since the latest Jurassic, Earth Science Reviews, 162, 293-337. The … Read more…

Palaeolatitudinal distribution of lithologic indicators of climate in a palaeogeographic framework

Citation: Cao, W., Williams, S., Flament, N., Zahirovic, S., Scotese, C., and Müller, R. D., 2018. Paleolatitudinal distribution of lithologic indicators of climate in a paleogeographic framework. Geological Magazine, 1-24. Abstract: Whether the latitudinal distribution of climate-sensitive lithologies is stable through greenhouse and icehouse regimes remains unclear. Previous studies suggest that the palaeolatitudinal distribution of palaeoclimate … Read more…

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…

Influence of mantle flow on the drainage of eastern Australia since the Jurassic period

Author List: Tristan Salles, Nicolas Flament & Dietmar Müller. Citation: Salles, Tristan & Flament, Nicolas & Müller, Dietmar. (2017). Influence of mantle flow on the drainage of eastern Australia since the Jurassic Period. Geochemistry, Geophysics, Geosystems. 18. . 10.1002/2016GC006617. Abstract:  Recent studies of the past eastern Australian landscape from present-day longitudinal river profiles and from mantle flow models … Read more…

Dynamic topography and eustasy controlled the paleogeographic evolution of northern Africa since the mid-Cretaceous

Author List: Nicholas Barnett-Moore, Rakib Hassan, Dietmar Müller, Simon Williams & Nicolas Flament. Citation: Barnett-Moore, Nicholas & Hassan, Rakib & Müller, Dietmar & Williams, Simon & Flament, Nicolas. (2017). Dynamic topography and eustasy controlled the paleogeographic evolution of northern Africa since the mid Cretaceous. Tectonics. . 10.1002/2016tc004280. Abstract: Northern Africa underwent widespread inundation during the Late Cretaceous. Changes … Read more…

Origin and evolution of the deep thermochemical structure beneath Eurasia

Author List: Nicolas Flament, Simon Williams, Dietmar Müller, Michael Gurnis & Dan Bower. Citation: Flament, Nicolas & Williams, Simon & Müller, Dietmar & Gurnis, Michael & J. Bower, Dan. (2017). Origin and evolution of the deep thermochemical structure beneath Eurasia. Nature Communications. 8. . 10.1038/ncomms14164. Abstract: A unique structure in the Earth’s lowermost mantle, the Perm Anomaly, was … 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…

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

Author List: Dietmar Müller, Rakib Hassan, Michael Garnis, Nicolas Flament, Simon Williams. Citation: Müller, Dietmar & Hassan, Rakib & Gurnis, M & Flament, Nicolas & Williams, Simon. (2018). Dynamic topography of passive continental margins and their hinterlands since the Cretaceous. Gondwana Research. . 10.1016/j.gr.2017.04.028. Abstract: Even though it is well accepted that the Earth’s surface topography has been … Read more…

Rodinia conference in Townsville reviews progress and challenges in reconstructing ancient supercontinents

Several EarthByters presented talks at the Rodinia 2017 conference in Townsville, including Dietmar Müller, Andrew Merdith, Simon Williams, Mike Tetley and Nicolas Flament.  The conference was opened by two talks by Alan Collins (Univ. Adelaide) and Andrew, presenting their new Proterozoic Rodinia plate model with continuously closing plate boundaries that were recently published in Gondwana … Read more…

EarthByters selected as exceptional reviewers for GSA journals

EarthByters selected as exceptional reviewers for GSA journals Several Australian geologists and geophysicists have been selected as exceptional reviewers for Geological Society of America journals, for prompt, insightful, meticulous, and tactful reviews. Nicolas Flament was selected for his reviews of Lithosphere papers, and Dietmar Muller for Geosphere reviews. Other Australians honoured for their quality reviews … Read more…

Basin Genesis Hub computer model explains Early Cretaceous eastward flow of ancient Murray River

Murray_RiverAustralia is an outstanding natural laboratory to study the influence of dynamic topography on landscape evolution, having been largely unaffected by tectonic deformation since the Jurassic. Recent studies of the past eastern Australian landscape from present-day longitudinal river profiles and from mantle flow models suggest that the interaction of plate motion with mantle convection accounts for the two phases of large-scale uplift of the region since 120 Ma. … Read more…

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EarthByters find that death of ancient ocean between China and Russia triggered mantle upwelling

Flament_Figure5A collaboration between the University of Wollongong, the EarthByte Group at the University of Sydney, the California Institute of Technology and ETH Zürich have solved the mystery of the formation of a recently discovered structure 2,500 km below the city of Perm in Russia.

Earth’s lowermost rocky mantle, just above its iron-rich core, is characterised by two giant hot upwellings under the Pacific Ocean and Africa. Many islands in the Pacific and around Africa owe their volcanic activity to “hotspots” within these large, hot regions deep underneath the surface.  … Read more…

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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…

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Large fluctuations of shallow seas in low-lying Southeast Asia driven by mantle flow

Author List: Sabin Zahirovic, Nicolas Flament, Dietmar Müller, Maria Seton, Mike Gurnis. Citation: Zahirovic, S., Flament, N., Müller, R.D., Seton, M., and Gurnis, M. (2016). Large fluctuations of shallow seas in low-lying Southeast Asia driven by mantle flow. Geochemistry, Geophysics, Geosystems. doi:10.1002/2016GC006434 The Sundaland continental promontory, as the core of Southeast Asia, is one of the lowest lying … Read more…

A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow

Author List: Rakib Hassan, Dietmar Müller, Mike Gurnis, Simon Williams and Nicolas Flament Citation: Hassan, R., Müller, R.D., Gurnis, M., Williams, S.E. and Flament, N. (2016). A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow. Nature, 533, 239-242. doi:10.1038/nature17422 Abstract: Volcanic hotspot tracks featuring linear progressions in the age of volcanism … Read more…

How the Hawaiian-Emperor seamount chain got its spectacular bend

In a paper published in Nature, Rakib Hassan with fellow EarthByters Dietmar Müller, Simon E. Williams & Nicolas Flament, and Caltech’s Michael Gurnis, proposed a solution to a long standing geological mystery – how the distinct bend in the Hawaiian-Emperor Seamount Chain came to be. Using NCI’s Raijin supercomputer, the research team simulated flow patterns in the Earth’s mantle over the past 100 million years. The convection model suggests that the history of subduction has a profound effect on the time-dependent deformation of the edges of the Large Low-Shear Velocity Province (LLSVP) under the Pacific. The Hawaiian plume originates from the edge of this province and the southward migration of the plume during the formation of the Emperor chain reflects the migration of the northern edge of the LLSVP before ~47 million years ago. 
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Geologists Discover How Australia’s Highest Mountain Formed

Eastern_australia_topographyCongratulations to Prof Dietmar Müller, Dr Nicolas Flament, Dr Kara Matthews, Dr Simon Williams, and Prof Michael Gurnis on their paper recently published in Earth and Planetary Science Letters. Their paper, Formation of Australian continental margin highlands driven by plate-mantle interaction, has featured in a variety of Australian and international media outlets.

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Geologists Discover How Australia’s Highest Mountain Formed – Media Release

Eastern_australia_topographyGeologists from the University of Sydney and the California Institute of Technology have solved the mystery of how Australia’s highest mountain – Mount Kosciusko – and surrounding alps came to exist.

Most of the world’s mountain belts are the result of two continents colliding (including the Himalayas) or volcanism. The mountains of Australia’s Eastern highlands – stretching from north-eastern Queensland to western Victoria – are an exception. Until now no one knew how they formed.

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PLOS ONE – The GPlates Portal: Cloud-Based Interactive 3D Visualization of Global Geophysical and Geological Data in a Web Browser

Author List: Dietmar Müller, Xiaodong Qin, David Sandwell, Adriana Dutkiewicz, Simon Williams, Nicolas Flament, Stefan Maus, Maria Seton Citation: Müller, R. D., Qin, X., Sandwell, D. T., Dutkiewicz, A., Williams, S. E., Flament, N., Maus, S., & Seton, M. (2016). The GPlates Portal: Cloud-Based Interactive 3D Visualization of Global Geophysical and Geological Data in a Web Browser. … Read more…

Earth and Planetary Science Letters – Formation of Australian continental margin highlands driven by plate–mantle interaction

Author List: Dietmar Müller, Nicolas Flament, Kara Matthews, Simon Williams and Mike Gurnis Citation: Müller, R. D., Flament, N., Matthews, K. J., Williams, S. E., & Gurnis, M. (2016). Formation of Australian continental margin highlands driven by plate–mantle interaction. Earth and Planetary Science Letters, 441, 60–70. http://dx.doi.org/10.1016/j.epsl.2016.02.025 Formation of Australian continental margin highlands driven by plate–mantle … Read more…