News 2020

Identifying Characteristic and Anomalous Mantle From the Complex Relationship Between Abyssal Hill Roughness and Spreading Rates

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The dependence of abyssal hill roughness on mid-ocean ridge (MOR) spreading rate is an important indicator for faulting and volcanism. I reanalyze this relationship using a global gravity-based prediction of root-mean-square (RMS) heights, enabling dense sampling of RMS/spreading rate space and thus a far more detailed examination than possible with bathymetric data. RMS histograms are … Read more…

Intraplate volcanism triggered by bursts in slab flux

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Long-lived, widespread intraplate volcanism without age progression is one of the most controversial features of plate tectonics. Previously proposed edge-driven convection, asthenospheric shear, and lithospheric detachment fail to explain the ~5000-km-wide intraplate volcanic province from eastern Australia to Zealandia. We model the subducted slab volume over 100 million years and find that slab flux drives … Read more…

Coupled evolution of plate tectonics and basal mantle structure

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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…

Paper in Frontiers of Earth Science: Modeling the Dynamic Landscape Evolution of a Volcanic Coastal Environment Under Future Climate Trajectories

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Modeling the Dynamic Landscape Evolution of a Volcanic Coastal Environment Under Future Climate Trajectories Kyle Manley, T. Salles and R. D. Müller As anthropogenic forcing continues to rapidly modify worldwide climate, impacts on landscape changes will grow. Olivine weathering is a natural process that sequesters carbon out of the atmosphere, but is now being proposed … Read more…

Environmental predictors of deep-sea polymetallic nodule occurrence in the global ocean

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Abstract: Polymetallic nodules found on the abyssal plains of the oceans represent one of the slowest known geological processes, and are a source of critical and rare metals for frontier technologies. A quantitative assessment of their occurrence worldwide has been hampered by a research focus on the northeastern Pacific Ocean and the lack of a … Read more…

Subduction history reveals Cretaceous slab superflux as a possible cause for the mid-Cretaceous plume pulse and superswell events

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Abstract: Subduction is a fundamental mechanism of material exchange between the planetary interior and the surface. Despite its significance, our current understanding of fluctuating subducting plate area and slab volume flux has been limited to a range of proxy estimates. Here we present a new detailed quantification of subduction zone parameters from the Late Triassic … Read more…

Integration of Selective Dimensionality Reduction Techniques for Mineral Exploration Using ASTER Satellite Data

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Abstract: There are a significant number of image processing methods that have been developed during the past decades for detecting anomalous areas, such as hydrothermal alteration zones, using satellite images. Among these methods, dimensionality reduction or transformation techniques are known to be a robust type of methods, which are helpful, as they reduce the extent … Read more…

East African topography and volcanism explained by a single, migrating plume

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Abstract: Anomalous topographic swells and Cenozoic volcanism in east Africa have been associated with mantle plumes. Several models involving one or more fixed plumes beneath the northeastward migrating African plate have been suggested to explain the space-time distribution of magmatism in east Africa. We devise paleogeographically constrained global models of mantle convection and, based on … Read more…

Surrogate-assisted Bayesian inversion for landscape and basin evolution models

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Abstract: The complex and computationally expensive nature of landscape evolution models poses significant challenges to the inference and optimization of unknown model parameters. Bayesian inference provides a methodology for estimation and uncertainty quantification of unknown model parameters. In our previous work, we developed parallel tempering Bayeslands as a framework for parameter estimation and uncertainty quantification … Read more…

Bayesian geological and geophysical data fusion for the construction and uncertainty quantification of 3D geological models

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Abstract: Traditional approaches to develop 3D geological models employ a mix of quantitative and qualitative scientific techniques, which do not fully provide quantification of uncertainty in the constructed models and fail to optimally weight geological field observations against constraints from geophysical data. Here, using the Bayesian Obsidian software package, we develop a methodology to fuse … Read more…

Reconstructing seafloor age distributions in lost ocean basins

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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…

Concentration-concentration fractal modelling: a novel insight for correlation between variables in response to changes in the underlying controlling geological-geochemical processes

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Behnam Sadeghi has recently published a research paper in “Ore Geology Reviews”. This paper is based on one of the methods Behnam has developed in his PhD thesis. It is about a quite novel fractal model, named Concentration-Concentration (C-C), applied to geochemical anomaly classification. Also, in this paper Behnam has proposed a Bayesian framework, using … Read more…

Controls on soil geochemistry fractal characteristics in Lemesos (Limassol), Cyprus

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Behnam Sadeghi has recently published a research paper about urban geochemistry in Cyprus, based on soil data, and using fractal models and statistical analysis. A part of this paper is from his PhD thesis. This is a collaborative project with the Geological Survey of Cyprus and UNSW School of Biological, Earth and Environmental Sciences. ABSTRACT: This … Read more…

PhD Scholarship in Spatio-Temporal Data Mining for Mineral Exploration

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Postgraduate research scholarship at the EarthByte Group Up to $105,000 stipend scholarship to support a PhD student to research spatio-temporal data mining for mineral exploration. Highlights Value Eligibility Open date Closing date $35,000 pa (for up to 3 years) Full-time PhD student at the School of Geosciences Hold an honours or master’s degree 1 September 2020 … Read more…

PhD scholarship in plate-plume interactions

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Postgraduate research scholarship at the EarthByte Group Up to $84,000 stipend scholarship to support a PhD student to research plate-plume interactions.   Highlights Value Eligibility $28,000 pa (for up to 3 years) Full-time PhD student at the School of Geosciences Hold an honours or master’s degree How to apply Send expressions of interest to Dr … Read more…

A global dataset of present-day oceanic crustal age and seafloor spreading parameters

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Abstract: We present an updated oceanic crustal age grid and a set of complementary grids including spreading rate, asymmetry, direction and obliquity. Our dataset is based on a selected set of magnetic anomaly identifications and the plate tectonic model of Müller et al. (2019). We find the mean age of oceanic crust is 64.2 Myrs, … Read more…

Kinematic and geodynamic evolution of the Isthmus of Panama region: Implications for Central American Seaway closure

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Abstract: A major topic of debate in Earth and climate science surrounds the timing of closure of the Central American Seaway. While it is clear that the gateway was closed by ~2.8 Ma, recent studies based on geological and marine molecular evidence have suggested an earlier closing time of early to mid-Miocene. Here, we examine … Read more…

Sea level fluctuations driven by changes in global ocean basin volume following supercontinent break-up

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Abstract: Long-term variations in eustatic sea level in an ice-free world, which existed through most of the Mesozoic and early Cenozoic eras, are partly driven by changes in the volume of ocean basins. Previous studies have determined ocean basin volume changes from plate tectonic reconstructions since the Mesozoic; however, these studies have not considered a … Read more…

A Quantitative Tomotectonic Plate Reconstruction of Western North America and the Eastern Pacific Basin

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Abstract: Plate reconstructions since the breakup of Pangaea are mostly based on the preserved spreading history of ocean basins, within absolute reference frames that are constrained by a combination of age-progressive hotspot tracks and palaeomagnetic data. The evolution of destructive plate margins is difficult to constrain from surface observations as much of the evidence has … Read more…

Professor Dietmar Müller has been recognised as Australia’s research leader in the field of geophysics!

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✨Huge congratulations to Professor Dietmar Müller who has been recognised as Australia’s research leader in the field of geophysics! ✨ The Australian newspaper’s annual research awards acknowledge 17 scholars who are Australia’s leading researchers in chemical and material sciences – one selected from each of the 17 fields in this discipline. They are the researchers with … Read more…

PyGPlates now supports Python 3

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PyGPlates now supports Python 3.  You can download pyGPlates:   http://www.gplates.org/download.html What’s new in pyGPlates revision 28:- Windows and macOS support for Python 2.7, 3.5, 3.6, 3.7 and 3.8. macOS libraries signed and notarized by Apple (should no longer get security prompts). Ubuntu support for 16.04 LTS (Xenial), 18.04 LTS (Bionic), 19.10 (Eoan) and 20.04 LTS (Focal). Create topological features (dynamic … Read more…

PyBacktrack 1.3 now available as a Python package and a Docker image.

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PyBacktrack 1.3 is now available as a Python package and a Docker image. The documentation is available at: https://pybacktrack.readthedocs.io/en/latest/ Changes since version 1.2: Supports Python 3: please also use the recent pyGPlates Python 3 release. Added the following output columns: dynamic_topography: change in dynamic topography elevation since present day decompacted_depth: depth from fully decompacted layers (using surface porosity only) … Read more…

GPlates Portal passes 1 million views!

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Just in time for science week, our #AuScope supported GPlates Portal has passed 1 million views! The most popular globe remains the vertical gravity gradient globe which highlights the Earth’s lithospheric structure, followed by our seafloor lithology globe. For #ScienceWeek our portal guru Michael Chin has created a new globe for reconstructing the SRTM15 digital elevation model. Check it … Read more…

GPlates x Digital Directory: re-linking people with earth system science in an opportune moment of pause

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COVID-19 has stimulated both major behavioural change during lockdown; and new thoughts, experiments and even dreams as many of our human-created systems have come to a raging halt. As the traffic dims, we have the opportunity to ‘remind ourselves that we are embedded in a more-than-human world — and have some fun along the way … Read more…

Congratulations to Ömer Bodur for completing his Ph.D

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Ömer Bodur has satisfied the requirements for the award of the degree of Doctor of Philosophy (Science). Dr Ömer Bodur has completed his Ph.D. in 3 years, and he is currently pursuing his postdoc at the University of Wollongong. His thesis titled: On the Dynamics of Plate Tilting: An Analytical and Numerical Approach, was supervised by … Read more…

Visualizing the Deep Carbon Cycle

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Christian Fogerty, writing for American Geophysical Union (AGU)’s EoS magazine, reviews some of our work on modelling and visualising Earth’s deep carbon cycle. We started our exciting journey with the Deep Carbon Observatory (DCO) in 2015, and these projects have laid the foundations of a lot of exciting future work. Importantly, the team behind the … Read more…

Paper in Geological Society London Memoirs: Geodynamics of the SW Pacific: a brief review and relations with New Caledonian geology

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A book chapter in: New Caledonia: Geology, Geodynamic Evolution and Mineral Resources. Geological Society, London, Memoirs, 51, 13–26, https://doi.org/10.1144/M51-2018-5 has finally been published. The book chapter, which gives a brief overview of the geodynamics of New Caledonia, was a collaboration between colleagues from New Caledonia, New Zealand, Australia and France. Abstract below: The SW Pacific … Read more…