PLATO – PLAte Tectonics and Ore deposits

Project PLATO is an ARC Linkage project as a collaboration between the EarthByte Group and Lithodat. CIs, PIs and AIs include Dietmar Müller (Usyd) Maria Seton (Usyd) Sabin Zahirovic (Usyd) Sara Polanco (Usyd) Brent McInnes (Curtin Univ.) Fabian Kohlmann (Lithodat) In addition, Dr Ehsan Farahbakhsh is a research fellow and Elnaz Heidari is a PhD student … Read more…

PNAS: Earth’s interior dynamics drive marine fossil diversity cycles of tens of millions of years

The fossil record reveals that biotic diversity has fluctuated quasi-cyclically through geological time. However, the causal mechanisms of biotic diversity cycles remain unexplained. Here, we highlight a common, correlatable 36 ± 1 Myr (million years) cycle in the diversity of marine genera as well as in tectonic, sea-level, and macrostratigraphic data over the past 250 … Read more…

Tectonics: Modeling Lithospheric Thickness Along the Conjugate South Atlantic Passive Margins Implies Asymmetric Rift Initiation

The lithospheric architecture of passive margins is crucial for understanding the tectonic processes that caused the breakup of Gondwana. We highlight the evolution of the South Atlantic passive margins by a simple thermal lithosphere-asthenosphere boundary (LAB) model based on onset and cessation of rifting, crustal thickness, and stretching factors. We simulate lithospheric thinning and select … Read more…

The formation of atolls: new insights from numerical simulations

Several theories have been proposed to explain atoll formation. While karst dissolution during glacial periods and preferential coral reef accretion along raised bank margins during deglaciations and interglacials have been invoked to explain atoll formation, the respective roles of karst dissolution and reef margin construction in atoll formation have not been adequately evaluated by simulations. … Read more…

Nature Communications: Coupled influence of tectonics, climate, and surface processes on landscape evolution in southwestern North America

The Cenozoic landscape evolution in southwestern North America is ascribed to crustal isostasy, dynamic topography, or lithosphere tectonics, but their relative contributions remain controversial. Here we reconstruct landscape history since the late Eocene by investigating the interplay between mantle convection, lithosphere dynamics, climate, and surface pro- cesses using fully coupled four-dimensional numerical models. Our quantified … 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…

G-cubed: Slow Geodynamics and Fast Morphotectonics in the Far East Tethys

How can the sluggish, long-wavelength mantle convection be expressed by so many time and space scales of morphotectonic activity? To investigate these relationships, we explore the Java-Banda subduction zone, where geodynamic records cluster. In the far-East Tethys, the exceptionally arcuate Banda subduction zone circumscribes the deepest oceanic basin on Earth, seismotectonic activity slices the upper … Read more…

Marine and Petroleum Geology: Single-phase vs two-phase rifting: Numerical perspectives on the accommodation of extension during continental break-up

How continental lithosphere responds to extension is a function of the dynamic interaction between layers of differing rheological properties, including the shallow crust, deep crust, lithospheric mantle, and asthenosphere. We investigate the first-order controls on the modes of extension and timing of transition from continental rifting to development of continental margins via a suite of … Read more…

Basin Research: Modelling the role of dynamic topography and eustasy in the evolution of the Great Artesian Basin

Widespread flooding of the Australian continent during the Early Cretaceous, referred to as the Eromanga Sea, deposited extensive shallow marine sediments throughout the Great Artesian Basin (GAB). This event had been considered ‘out of sync’ with eustatic sea level and was instead solely attributed to dynamic subsidence associated with Australia’s passage over eastern Gondwanan subducted … Read more…

G-Cubed: Papanin Ridge and Ojin Rise Seamounts (Northwest Pacific): Dual Hotspot Tracks Formed by the Shatsky Plume

The origin of Shatsky Rise, a large igneous plateau in the NW Pacific, has long been debated. It could have either formed by shallow mantle melting due to its confirmed creation along a mid-ocean ridge or with additional contribution of deeper mantle material that upwelled as so-called mantle plume beneath the spreading ridge (“plume-ridge interaction”). … Read more…

STELLAR – Spatio TEmporaL expLorAtion for Resources

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Project STELLAR (Spatio TEmporaL expLorAtion for Resources) is a collaboration between BHP and the EarthByte Group aimed at implementing big and complex spatio-temporal data analysis and modelling to support the needs of BHP in global resource exploration. Split into multiple phases over the next 3.5 years, the project will connect BHP’s warehouse of global resource knowledge with … Read more…

Potential encoding of coupling between Milankovitch forcing and Earth’s interior processes in the Phanerozoic eustatic sea-level record

The driving mechanisms of Earth’s climate system at a multi-Myr timescale have received considerable attention since the 1980’s as they are deemed to control large-amplitude climatic variations that result in severe biogeochemical disruptions, major sea-level variations, and the evolution of Earth’s land- and seascapes through geological time. The commonly accepted mechanism for these changes derives … Read more…

The carbonate compensation depth in the South Atlantic Ocean since the Late Cretaceous

Carbonate accumulation rates (CAR) in the South Atlantic through time, with the average CCD for the South Atlantic shown in black, which the CCD in the Walvis Ridge/Rio Grande Rise area is shown in magenta. Deep-sea carbonate deposition is a complex process that is encapsulated in the carbonate compensation depth (CCD)—a facies boundary separating calcareous … Read more…

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

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

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

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

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

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

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

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…

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

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

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

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

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…

MinEx CRC PhD project: Bayesian optimisation for drill site selection

MinEx CRC PhD project: Bayesian optimisation for drill site selection at the University of South Australia, the School of Geosciences, University of Sydney and Geoscience Australia, including the Centre for Translational Data Science and the EarthByte Group. Download the MinEx pgrad booklet at https://buff.ly/2N5DLJ0

Muller et al. (2019) deforming plate reconstructions and associated digital supplements (Tectonics)

A Global Plate Model Including Lithospheric Deformation Along Major Rifts and Orogens Since the Triassic R. Dietmar Müller, Sabin Zahirovic, Simon E. Williams, John Cannon, Maria Seton, Dan J. Bower, Michael G. Tetley, Christian Heine, Eline Le Breton, Shaofeng Liu, Samuel H. J. Russell, Ting Yang, Jonathon Leonard, and Michael Gurnis Journal: Tectonics (open access) … Read more…

Continental breakup triggered massive CO2 emissions

Plate Models

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…

A global review and digital database of large-scale extinct spreading centers

Author List: Sarah MacLeod, Simon Williams, Kara Matthews, Dietmar Müller and Xiaodong Qin Citation: MacLeod, S.J., Williams, S.E., Matthews, K.J., Müller, R.D. and Qin, X., 2017. A global review and digital database of large-scale extinct spreading centers. Geosphere, pp.GES01379-1. Abstract: Extinct mid-ocean ridges record past plate boundary reorganizations, and identifying their locations is crucial to developing a better understanding of the … Read more…