Deep Carbon Cycling Over the Past 200 Million Years: A Review of Fluxes in Different Tectonic Settings

Abstract: Carbon is a key control on the surface chemistry and climate of Earth. Significant volumes of carbon are input to the oceans and atmosphere from deep Earth in the form of degassed CO2 and are returned to large carbon reservoirs in the mantle via subduction or burial. Different tectonic settings (e.g., volcanic arcs, mid-ocean … Read more…

Rift and plate boundary evolution across two supercontinent cycles

Citation: Merdith, Andrew & Williams, Simon & Brune, Sascha & Collins Alan, S & Müller, Dietmar. (2018). Rift and plate boundary evolution across two supercontinent cycles. Global and Planetary Change. 173. 10.1016/j.gloplacha.2018.11.006. Abstract The extent of continental rifts and subduction zones through deep geological time provides insights into the mechanisms behind supercontinent cycles and the long term evolution of the mantle. … Read more…

Rift and plate boundary evolution across two super-continent cycles

Abstract The extent of continental rifts and subduction zones through deep geological time provides insights into the mechanisms behind supercontinent cycles and the long term evolution of the mantle. However, previous compilations have stopped short of mapping the locations of rifts and subduction zones continuously since the Neoproterozoic and within a self-consistent plate kinematic framework. … Read more…

Oblique rifting: the rule, not the exception

Abstract: Movements of tectonic plates often induce oblique deformation at divergent plate boundaries. This is in striking contrast with traditional conceptual models of rifting and rifted margin formation, which often assume 2-D deformation where the rift velocity is oriented perpendicular to the plate boundary. Here we quantify the validity of this assumption by analysing the kinematics … Read more…

New interactive rift obliquity globe on the GPlates Portal

The ARC Basin Genesis Hub has made a new interactive rift obliquity globe available on the GPlates Portal at http://portal.gplates.org/cesium/?view=rift_ov, based on a recently published paper entitled “Oblique rifting: the rule, not the exception” in Solid Earth. This virtual globe visualizes extension velocities and obliquities within Earth’s major post-Pangea rift systems. Each circle depicts the … Read more…

Degassing from Continental Rifts Controls Earth’s Thermostat

As a greenhouse gas, carbon dioxide in the atmosphere has played a major role in regulating Earth’s climate throughout its history. There are vast stores of carbon in the subsurface, but the global carbon cycle controls how much of that carbon enters the atmosphere. As methods for monitoring and tracking the carbon dioxide that moves … Read more…

Continental breakup triggered massive CO2 emissions

Currently, human activity is the primary driver of elevating atmospheric CO2, but the Earth fluctuated from greenhouse to icehouse conditions and back long before humans existed. The question is:  what triggered these long-term climate cycles? Now research at the University of Sydney’s EarthByte Group, in collaboration with the German Research Centre for Geosciences, reveals how … Read more…

EarthByte Honours and Masters Projects 2018

EarthByte globe icon

EarthByte has now released a list of Honours/Masters projects to be offered in 2018. These projects are outlined below. Project Title Supervisor(s) Dynamic Earth models, landscape dynamics and basin evolution in Australasia Dietmar Müller, Sabin Zahirovic, Tristan Salles, Rohit Chandra, Sally Cripps (Centre for Translational Data Science) Incorporating modern plate tectonic reconstructions into box models of the deep-time deep-Earth … Read more…

Global patterns in Earth’s dynamic topography since the Jurassic: the role of subducted slabs

Author List: Michael Rubey, Sascha Brune, Christian Heine, Rhodri Davies, Simon Williams, and Dietmar Müller. Citation: Rubey, M., Brune, S., Heine, C., Davies, D. R., Williams, S. E., and Müller, R. D.: Global patterns in Earth’s dynamic topography since the Jurassic: the role of subducted slabs, Solid Earth, 8, 899-919, https://doi.org/10.5194/se-8-899-2017, 2017. Abstract: We evaluate the spatial … Read more…

Abrupt plate accelerations shape rifted continental margins

Author List: Sascha Brune, Simon Williams, Nathaniel Butterworth and Dietmar Müller. Citation: Brune, S., Williams, S.E, Butterworth, N. P., and Müller, R.D. (2016). Abrupt plate accelerations shape rifted continental margins. Nature, 1–4. doi:10.1038/nature18319 Abstract: Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension … Read more…

The pains and strains of a continental breakup in the media

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View of Australia’s western continental margin, looking eastwards from the Indian Ocean.

Congratulations to Dr Sascha Brune, Dr Simon Williams, Dr Nathan Butterworth, and Prof Dietmar Müller on their paper published in Nature earlier this week. The paper,  Abrupt plate accelerations shape rifted continental marginshas been picked up by the media across the globe.

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The pains and strains of a continental breakup

Every now and then in Earth’s history, a pair of continents draws close enough to form one. There comes a time, however, when they must inevitably part ways. Now scientists at Australia’s EarthByte research group, in collaboration with the German Research Centre for Geosciences, have revealed the underlying mechanics of a continental breakup when this … Read more…

Earth and Planetary Science Letters – Climate changes control offshore crustal structure at South China Sea continental margin

Clift, P. D., Brune, S., & Quinteros, J. (2015). Climate changes control offshore crustal structure at South China Sea continental margin. Earth and Planetary Science Letters, 420, 66-72. doi: 10.1016/j.epsl.2015.03.032. Climate changes control offshore crustal structure at South China Sea continental margin Download supporting information – pdf

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…

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Evolution of stress and fault patterns in oblique rift systems: 3D numerical lithospheric-scale experiments from rift to breakup

Rifting involves complex normal fault systems that are controlled by extension direction, reactivation of pre-rift structures, sedimentation, and dyke dynamics. The relative impact of these factors on the observed fault pattern, however, is difficult to deduce from field-based studies alone.

This study provides insight in crustal stress patterns and fault orientations by employing a laterally homogeneous, 3D rift setup with constant extension velocity. The presented numerical forward experiments cover the whole spectrum of oblique extension. They are conducted using an elasto-visco-plastic finite element model and involve crustal and mantle layers accounting for self-consistent necking of the lithosphere. … Read more…

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Geochemistry, Geophysics, Geosystems – Evolution of stress and fault patterns in oblique rift systems: 3-D numerical lithospheric-scale experiments from rift to breakup

Brune, S. (2014). Evolution of stress and fault patterns in oblique rift systems: 3‐D numerical lithospheric‐scale experiments from rift to breakupGeochemistry, Geophysics, Geosystems, 15(8), 3392-3415. doi: 10.1002/2014GC005446.

Evolution of stress and fault patterns in oblique rift systems: 3‐D numerical lithospheric‐scale experiments from rift to breakup

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Nature Communications – Rift migration explains continental margin assymetry and crustal hyper-extension

Brune, S., Heine, C., Pérez-Gussinyé, M., & Sobolev, S. V. (2014). Rift migration explains continental margin asymmetry and crustal hyper-extension. Nature communications, 5. doi: 10.1038/ncomms5014. Rift migration explains continental margin asymmetry and crustal hyper-extension Download supplementary information – pdf

Rift migration explains continental margin asymmetry and crustal hyper-extension

Rift MigrationWhen continents break apart, continental crust and lithosphere are thinned until break-up is achieved and an oceanic basin is formed. The most remarkable and least understood structures associated with this process are up to 200 km wide areas of hyper-extended continental crust, which are partitioned between conjugate margins with pronounced asymmetry. Here we show, using high-resolution thermo-mechanical modelling, that hyper-extended crust and margin asymmetry are produced by steady state rift migration. … Read more…

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EarthByte publicity for Oblique rifting of the Equatorial Atlantic paper

Summary FigureCongratulations to EarthByte’s Sascha Brune and Christian Heine (now at Shell in The Hague) who made it to the Sydney Uni front page with a media piece on “How the world missed out on a Saharan Atlantic ocean”, attracted international media attention and were chosen as a “Research Focus” in the current volume of Geology for their paper: Oblique rifting of the Equatorial Atlantic: Why there is no Saharan Atlantic Ocean. Well done! … Read more…

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Geology – Oblique rifting of the Equatorial Atlantic: Why there is no Saharan Atlantic Ocean

Heine, C., & Brune, S. (2014). Oblique rifting of the Equatorial Atlantic: why there is no Saharan Atlantic Ocean. Geology, 42(3), 211-214. doi:10.1130/G35082.1 107-199. Oblique rifting of the Equatorial Atlantic: why there is no Saharan Atlantic Ocean Access supporting data (ref. 2014073)

Tectonophysics – The rift to break-up evolution of the Gulf of Aden: Insights from 3D numerical lithospheric-scale modelling

Brune, S., & Autin, J. (2013). The rift to break-up evolution of the Gulf of Aden: Insights from 3D numerical lithospheric-scale modelling. Tectonophysics, 607, 65-79. doi:10.1016/j.tecto.2013.06.029. The rift to break-up evolution of the Gulf of Aden: Insights from 3D numerical lithospheric-scale modelling