Mars attracts: how Earth’s planetary interactions drive deep-sea circulation

12 March 2024, The University of Sydney Media Release Giant whirlpools in warming oceans could mitigate Gulf Stream stagnation Geoscientists at Sydney and Sorbonne have identified a 2.4-million-year cycle in the geological record that show the energy of deep-sea currents wax and wane as oceans cool and warm. Earth’s distance to Mars varies between 55 … Read more…

Nature Communications: Deep-sea hiatus record reveals orbital pacing by 2.4 Myr eccentricity grand cycles

Astronomical forcing of Earth’s climate is embedded in the rhythms of stratigraphic records, most famously as short-period (10^4–10^5 year) Milankovitch cycles. Astronomical grand cycles with periods of millions of years also modulate climate variability but have been detected in relatively few proxy records. Here, we apply spectral analysis to a dataset of Cenozoic deep-sea hiatuses … Read more…

AuScope News: EarthByters unveil Ice Age secrets

Notebook resting on an Ice Age or the transition from the Tonian Skillogallee and Myrtle Springs Formations to the overlying Cryogenian Sturt Formation (Sturt Glaciation, marked by the notebook) in the Willouran Ranges, Adnyamathanha Country, South Australia. Image: Alan Collins ARC Future Fellow Dr Adriana Dutkiewicz from the EarthByte Group and colleagues have used NCRIS … Read more…

New data set for refined boundaries between continental and ocean crust released

Earth’s topography and bathymetry with revised boundaries between continental and ocean crust overlain as thin red lines. We have released a refined data set of the boundaries between continental and ocean crust (COBs). The data can be downloaded from zenodo as GPlates-compatible gpmlz and as ESRI shapefile. The COBs are based on the data set … Read more…

Geology: Submarine volcanism along shallow ridges did not drive Cryogenian cap carbonate formation

The termination of Neoproterozoic “Snowball Earth” glaciations is marked globally by laterally extensive neritic cap carbonates directly overlying glacial diamictites. The formation of these unique deposits on deglaciation calls for anomalously high CaCO3 saturation. A popular mechanism to account for the source of requisite ocean alkalinity is the shallow-ridge hypothesis, in which initial spreading ridges … Read more…

Geology: Duration of Sturtian “Snowball Earth” glaciation linked to exceptionally low mid-ocean ridge outgassing

The Sturtian ‘Snowball Earth’ glaciation (~717–661 Ma) is regarded as the most extreme interval of icehouse climate in Earth’s history. The exact trigger and sustention mechanisms for this long-lived global glaciation remain obscure. The most widely debated causes are silicate weathering of the ~718 Ma Franklin LIP, and changes in the length and degassing of … Read more…

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

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…

Evolution of Earth’s tectonic carbon conveyor belt

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…

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

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…

When the Earth warms, the ocean speeds up

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

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…

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

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…

PhD scholarship in Deep-Sea Sediments and Paleoclimate

This PhD project with Dr. Adriana Dutkiewicz in the Univ. of Sydney EarthByte Group is aimed at reconstructing the evolution of the deep-sea carbon reservoir and its impact on the long-term global carbon cycle as part of an ARC-funded Future Fellowship. It includes a stipend allowance of $28,854 per annum for three years (with an … 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…

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

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…

EarthByte Honours and Masters Projects 2020

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EarthByte has now released a list of Honours/Masters projects to be offered in 2020. These projects are outlined below. We can also tailor projects to your interests. Feel free to contact us by clicking the supervisor links below. Project Title Supervisor(s) How climate and subsidence control the sedimentation along the Norwegian Margin? Claire Mallard , … Read more…

How marine snow cools the planet

University of Sydney scientists have modelled how carbonate accumulation from ‘marine snow’ in oceans has absorbed carbon dioxide over millennia and been a key driver in keeping the planet cool for millions of years. Researchers in the School of Geosciences have mapped out how carbonate formations have helped regulate Earth’s temperature over 120 million years. … Read more…

Carbon Down Under workshop – 24 to 26 July 2019

Carbon Down Under

We are excited to announce a Sydney-based workshop that will bring existing and emerging leaders in deep carbon research to discuss the state of the discipline, but importantly a plan for future collaboration that builds on the momentum generated by the Deep Carbon Observatory. The workshop will be held on Wednesday and Thursday 24 and … Read more…

Sequestration and subduction of deep-sea carbonate in the global ocean since the Early Cretaceous

Citation: Dutkiewicz, Adriana & Müller, Dietmar & Cannon, John & Vaughan, Sioned & Zahirovic, Sabin. (2018). Sequestration and subduction of deep-sea carbonate in the global ocean since the Early Cretaceous. Geology. 10.1130/G45424.1. Abstract Deep-sea carbonate represents Earth’s largest carbon sink and one of the least-known components of the long-term carbon cycle that is intimately linked … Read more…

Mapping the Growth of Seafloor Carbonates in Deep Time

A news article published by the Deep Carbon Observatory entitled “Mapping the Growth of Seafloor Carbonates in Deep Time” explains how Adriana Dutkiewicz and colleagues used records of carbonate layers logged from cores collected during scientific ocean drilling expeditions combined with a model of ocean basin evolution to unravel the role deep sea carbonate deposition might have … Read more…

Roberto Spina reviews the future of Big Data and Artificial Intelligence Analytics in Geosciences

Roberto Spina, a computational geologist from Italy, wrote a lead article in GSA Today, in which he reviews the future of Big Data and Artificial Intelligence Analytics in Geosciences, using Adriana Dutkiwicz’s digital seafloor lithology map published 3 years ago as a ground-breaking example. The article includes a South Atlantic view of the virtual globe portraying her map, … Read more…

EarthByte Honours and Masters Projects 2019

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EarthByte has now released a list of Honours/Masters projects to be offered in 2019. These projects are outlined below. Project Title Supervisor(s) How is landscape complexity driving biodiversity over geological time scales? Tristan Salles & Patrice Rey How well are tectonic and climatic signals preserved in the stratigraphic record? Tristan Salles & Claire Mallard Vertical motions … Read more…

PyBacktrack 1.0: a tool for reconstructing paleobathymetry on oceanic and continental crust

The pyBacktrack software package allows the backtracking of the paleo-water depth of ocean drill sites, providing a framework for reconstructing the accumulation history of sediment components through time. The software incorporates the effects of decompaction of common marine lithologies and allows backtracking of sites on both oceanic and continental crust.  Backtracking on ocean crust is based on … Read more…

Controls on the global distribution of contourite drifts: Insights from an eddy-resolving ocean model

Abstract Contourite drifts are anomalously high sediment accumulations that form due to reworking by bottom currents. Due to the lack of a comprehensive contourite database, the link between vigorous bottom water activity and drift occurrence has yet to be demonstrated on a global scale. Using an eddy-resolving ocean model and a new georeferenced database of 267 contourites, we show that the … Read more…

Oceanic crustal carbon cycle drives 26 million-year atmospheric carbon dioxide periodicities

Citation: Müller, R.D. and Dutkiewicz, A., 2018, Oceanic crustal carbon cycle drives 26 million-year atmospheric carbon dioxide periodicities, Science Advances, 4:eaaq0500, 1-7. Atmospheric carbon dioxide (CO2) data for the last 420 million years (My) show long-term fluctuations related to supercontinent cycles as well as shorter cycles at 26–32 My whose origin is unknown. Periodicities of 26–30 … Read more…

How seafloor weathering drives the slow carbon cycle

A previously unknown connection between geological atmospheric carbon dioxide cycles and the fluctuating capacity of the ocean crust to store carbon dioxide has been uncovered by two geoscientists from the University of Sydney. Prof Dietmar Müller and Dr Adriana Dutkiewicz from the Sydney Informatics Hub and the School of Geosciences report their discovery in the … Read more…

Predicting Sediment Thickness on Vanished Ocean Crust Since 200 Ma

Citation: Dutkiewicz, A., Müller, R.D., Wang, X., O’Callaghan, S., Cannon, J., Wright, N.M., 2017. Predicting sediment thickness on vanished ocean crust since 200 Ma. Geochemistry, Geophysics, Geosystems, 18, 4586–4603. Tracing sedimentation through time on existing and vanished seafloor is imperative for constraining long-term eustasy and for calculating volumes of subducted deep-sea sediments that contribute to global … Read more…

Understanding the Deep Carbon Cycle from Icehouse to Greenhouse Climates

Sydney Research Excellence Initiative grant (2017-2018) Research area, key questions, significance, and innovation. The planet is experiencing a major transition from an icehouse climate, one dominated by permanent continental ice sheets at high latitudes, to a greenhouse climate that favours ice-free conditions. Although part of the deglaciation trend is influenced by a natural orbital cycle, … Read more…

Taking the pulse of the global ocean

sediments_currents_global_oceanWhen organic particles sink from the surface ocean to the seafloor, a small but significant proportion of atmospheric carbon is stored away. Adriana Dutkiewicz and colleagues at the University of Sydney and Data61/CSIRO have now used global data sets collected over decades combined with cutting-edge big data analysis to understand how this process depends on surface ocean environments.   … Read more…

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Controls on the distribution of deep-sea sediments

Author List: Dr Adriana Dutkiewicz, Dr Simon O’Callaghan, Prof Dietmar Müller Citation: Dutkiewicz, A., O’Callaghan, S., and Müller, R.D. (2016). Controls on the distribution of deep-sea sediments. Geochemistry, Geophysics, Geosystems 17 1–24. doi:10.1002/2016GC006428 Abstract: Deep-sea sediments represent the largest geological deposit on Earth and provide a record of our planet’s response to conditions at the sea surface from … Read more…