Dietmar Müller

Geol. Soc. London Mem.: Effects of melt-percolation, refertilization and deformation on upper mantle seismic anisotropy: constraints from peridotite xenoliths, Marie Byrd Land, West Antarctica

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We report on the petrology, microstructure and seismic properties of 44 peridotite xenoliths extracted from the upper mantle beneath Marie Byrd Land (MBL), West Antarctica. The aim of this work is to understand how melt-rock reaction, refertilization, and deformation affected the seismic properties (velocities, anisotropy) of the West Antarctic upper mantle, in the context of … Read more…

Future Mining: Travelling through geological time to find copper deposits

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Travel through geological time to find copper deposits via our article in the inaugural issue of the Future Mining Magazine. https://future-mining.partica.online/future-mining/vol-1-no-1/flipbook/60/ Plate reconstructions at 1000, 400, 300, 200, 100 million years ago and at present-day. Ancient ocean basins are shown in white with continents in grey, and coloured arrows showing plate speed and direction. Mid-ocean … Read more…

Scientific Reports: Javanese Homo erectus on the move in SE Asia circa 1.8 Ma

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The migration of Homo erectus in Southeast Asia during Early Pleistocene is cardinal to our comprehension of the evolution of the genus Homo. However, the limited consideration of the rapidly changing physical environment, together with controversial datings of hominin bearing sites, make it challenging to secure the robust timeline needed to unveil the behavior of early humans. Here, … Read more…

Marine Geology: Tidal dynamics drive ooid formation in the Capricorn Channel since the Last Glacial Maximum

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Relative sea-level changes can dramatically alter coastal geomorphology and coastlines, which, in turn, can fundamentally alter tidal regimes. The Great Barrier Reef (GBR) has undergone around 120 m of relative sea level (RSL) rise since the Last Glacial Maximum, ∼20,000 years ago (ka). Ooid grains (sand sized carbonate sediment) that formed in shallow water (>5 m depth) … Read more…

Geoscience Letters: Geophysical model generation with generative adversarial networks

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With the rapid development of deep learning technologies, data-driven methods have become one of the main research focuses in geophysical inversion. Applications of various neural network architectures to the inversion of seismic, electromagnetic, gravity and other types of data confirm the potential of these methods in real-time parameter estimation without dependence on the starting subsurface … Read more…

Nature Reviews Earth and Environment: A glimpse into a possible geomorphic future of Tibet

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The Tibetan Plateau plays a central role in global atmospheric circulation, acts as a key biodiversity hotspot, and delivers fresh water for more than 20% of the global population. Projecting its future uplift and erosion trajectory over geological time can offer potential testable hypotheses into interactions between tectonic and surface processes. Rey, P., Salles, T., … Read more…

Geochemistry, Geophysics, Geosystems: The history of Cenozoic carbonate flux in the Atlantic Ocean constrained by multiple regional carbonate compensation depth reconstructions

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The Atlantic is the only ocean basin almost entirely surrounded by passive margins, and a major global long-term sink of carbonate carbon that has evaded subduction. Quantifying the history of carbonate accumulation in the Atlantic has been limited by the absence of well-defined regional carbonate compensation depth (CCD) models. We determine the CCD for the … Read more…

EOS: Billion-year rewind tracks supercontinents and mantle structures

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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…

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

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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…

Environmental stability on Earth allowed marine biodiversity to flourish

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Modern ocean biodiversity, which is at its highest level ever, was achieved through long-term stability of the location of so-called biodiversity hotspots, regions of especially high numbers of species, scientists have found. The findings, published in Nature, were reached through a pioneering model that reconstructs the diversity of marine animals from their origin – some … Read more…

Nature: Post-extinction recovery of the Phanerozoic oceans and biodiversity hotspots

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The fossil record of marine invertebrates has long fuelled the debate as to whether or not there are limits to global diversity in the sea. Ecological theory states that, as diversity grows and ecological niches are filled, the strengthening of biological interactions imposes limits on diversity. However, the extent to which biological interactions have constrained … 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

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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

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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…

Front Earth Sci: Two-step Gravity Inversion Reveals Variable Architecture of African Cratons

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The lithospheric build-up of the African continent is still to a large extent unexplored. In this contribution, we present a new Moho depth model to discuss the architecture of the three main African cratonic units, which are: West African Craton, Congo Craton, and Kalahari Craton. Our model is based on a two-step gravity inversion approach … Read more…

Extending full-plate tectonic models into deep time: Linking the Neoproterozoic and the Phanerozoic

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Recent progress in plate tectonic reconstructions has seen models move beyond the classical idea of continental drift by attempting to reconstruct the full evolving configuration of tectonic plates and plate boundaries. A particular problem for the Neoproterozoic and Cambrian is that many existing interpretations of geological and palaeomagnetic data have remained disconnected from younger, better-constrained … Read more…

Plate tectonic carbon cycle explains how Earth maintains a Goldilocks climate

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Earth’s hot and cold climates driven by tectonic plate speeds A new study has revealed how the plate tectonic carbon cycle maintains a “Goldilocks climate” on Earth that is neither too hot nor too cold. It is now established that CO2 emissions from burning fossil fuels are driving atmospheric CO2 above 400 parts per million … Read more…

Evolution of Earth’s tectonic carbon conveyor belt

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This video shows plate motions, carbon storage within tectonic plates and carbon degassing along mid-ocean ridges and subduction zones through time. Our carbon model shows these processes alone cannot explain global cooling in the Cenozoic Era. The effects of rock erosion, not shown here, played a key role. Arrows indicate plate motion speed relative to … Read more…

Postgraduate Research Scholarship in Deep-time exploration for mineral deposits along convergent margins

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Postgraduate research scholarship at the EarthByte Group for international and domestic students. Up to $107,850 stipend scholarship to support a PhD student to research in deep-time exploration for mineral deposits along convergent margins   Highlights Value Eligibility Open date Closing date $35,950 pa (for up to 3 years, with a possible 6 month extension) Full-time … Read more…

Part-time research assistant position in mineral exploration

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The EarthByte Group is looking for a research assistant as part of our STELLAR industry project in collaboration with BHP. The casual position will be for up to 10 hours per week on average. The successful applicant can complete these hours through a regular weekly schedule or clump their hours into intensive weekly blocks (i.e., … Read more…

ANZIC Forum 2022 Talk: Deep-sea hiatuses track the vigour of Cenozoic ocean bottom currents

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By Adriana Dutkiewicz Abstract: Scientific ocean drilling data collected over half a century have generated a treasure trove of data to map deep sea currents.  We have compiled data from more than 200 drill sites to map the continuity of the deep sea sedimentary record and to understand how global warming– or cooling – is … Read more…

Geoscience Data Journal: Subduction and carbonate platform interactions

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Plate tectonics, as the unifying theory in Earth sciences, controls the functioning of important planetary processes on geological timescales. Here, we present an open-source workflow that interrogates community digital plate tectonic reconstructions, primarily in the context of the planetary deep carbon cycle. We present an updated plate tectonic reconstruction covering the last 400 million years … Read more…

Terra Nova: Timing of partial melting and granulite formation during the genesis of high to ultra-high temperature terranes: Insight from numerical experiments

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Long-lived high to ultra-high temperature (HT-UHT) granulitic terranes formed throughout Earth’s history. Yet, the detailed processes involved in their formation re- main unresolved and notably the sequence of appearance and duration of migmatisa- tion and granulites conditions in the orogenic cycle. These processes can be evaluated by analytical and numerical models. First, solving the steady-state … Read more…

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

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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 number … Read more…

The use of machine learning in processing remote sensing data for mineral exploration

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ASEG will be hosting their next technical meeting on Wednesday 20th April, featuring EarthByter Ehsan Farahbakhsh Title: The use of machine learning in processing remote sensing data for mineral exploration     Time:                    5:30 pm for 6:00 pm start Address:              Level 2, 99 on York (99 York St, Sydney. Room ‘York 2’) For virtual attendance, … Read more…

Groundwater ‘superhighway’ modelled along Australia’s east coast

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When floodwaters recede, where do they go? By Loren Smith University of Sydney researchers have modelled water-storing aquifers that perform a natural balancing act: they absorb water during floods and supply water during drought. Yet human intervention is limiting their function. University of Sydney researchers have identified a groundwater ‘superhighway’ along Australia’s east coast. Stretching from … Read more…

When the Earth warms, the ocean speeds up

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Sixty-six million years of geological data suggests that heating makes ocean currents stronger. By Ellen McPhiddian, Cosmos Ocean currents play a big role in floods, droughts, and other large-scale weather patterns. We know that ocean circulation will be affected by global warming – but figuring out exactly how it will be affected is much more difficult. Will there be … Read more…

Global warming speeds up currents in the ocean’s abyss

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University of Sydney media release University of Sydney scientists have used the geological record of the deep sea to discover that past global warming has sped up deep ocean circulation. This is one of the missing links for predicting how future climate change may affect heat and carbon capture by the oceans. Circulation of the … Read more…

Nature Commmunications: Impact of green clay authigenesis on element sequestration in marine settings

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Retrograde clay mineral reactions (reverse weathering), including glauconite formation, are first-order controls on element sequestration in marine sediments. Here, we report substantial element sequestration by glauconite formation in shallow marine settings from the Triassic to the Holocene, averaging 3 ± 2 mmol·cm−²·kyr−1 for K, Mg and Al, 16 ± 9 mmol·cm−²·kyr−1 for Si and 6 ± 3 mmol·cm−²·kyr−1 for Fe, which is ~2 orders of magnitude higher … Read more…

Geology: Deep-sea hiatuses track the vigor of Cenozoic ocean bottom currents

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The deep-sea stratigraphic record is full of gaps. These hiatuses track changes in ocean circulation and chemistry, but determining their timing and causes has been limited by sparse data and incomplete knowledge of ocean gateway evolution in earlier studies. We combine a significantly expanded, age-calibrated deep-sea stratigraphic database with a global tectonic and paleo–water depth … Read more…

Scientific Reports: Constraining the response of continental‐scale groundwater flow to climate change

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Numerical models of groundwater flow play a critical role for water management scenarios under climate extremes. Large‐scale models play a key role in determining long-range flow pathways from continental interiors to the oceans, yet struggle to simulate the local flow patterns offered by small‐scale models. We have developed a highly scalable numerical framework to model … Read more…