Dietmar Müller 
Reposted from Earth Logs by Steve Drury The Cryogenian Period that lasted from 860 to 635 million years ago is aptly named, for it encompassed two maybe three episodes of glaciation. Each left a mark on every modern continent and extended from the poles to the Equator. In some way, this series of long, frigid … Read more…
8 February 2024, University of Sydney Media release Historically low volcanic emissions and weathering events seem likely cause Dr Adriana Dutkiewicz was inspired during a field trip to the Flinders Ranges to find out how volcanic activity turned our blue dot to an ice covered planet. Together with Professor Dietmar Muller and the EarthByte group, … Read more…
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…
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…
Since the Mesozoic, eastern NE Asia has experienced multiple tectonic events, resulting in a complex structure and forming one of the world’s largest Meso-Cenozoic lacustrine basin systems. Presently, basin evolution models require further elucidation regarding the simultaneous generation of diverse rift basins and the potential impact stemming from the closure of the Mudanjiang Ocean, whose … Read more…
We end 2023 with the release of GPlately1.3, with a number of bugfixes and improvements. The cool functionality of GPlately includes generating gridded oceanic crustal ages and seafloor spreading rates from plate models with evolving plate boundaries – see example below using a plate model in a mantle reference frame. Happy holidays from the EarthByte … Read more…
The long-term diversification of the biosphere responds to changes in the physical environment. Yet, over the continents, the nearly monotonic expansion of life started later in the early part of the Phanerozoic eon1 than the expansion in the marine realm, where instead the number of genera waxed and waned over time2. A comprehensive evaluation of … Read more…
We are excited to have Assoc Prof Caroline Tiddy from the University of South Australia visiting us in person to present her amazing work on new technologies in mineral exploration on Wednesday, 1 Nov, 1pm, Madsen Room 449. Abstract Our world is embarking on a green transition to see us move towards a low carbon … Read more…
For the past 250 million years, species have diversified and died out while Earth’s tectonic plate movements and sea level changes have operated in the background. They’re linked, according to new research that found that processes altering the lithosphere affect ocean levels and, in turn, the availability of shallow marine environments in which life thrives. “Why we … Read more…
We welcome our new postdoctoral researcher, Jianping Zhou, visiting for 2-3 years from the Ocean University of China in Qingdao. He obtained his undergraduate degree from Jilin University in China and completed his Ph.D. at the University of Göttingen, Germany. His research primarily focuses on the basin-and-range evolution in Eastern Asia and associated ore deposits. He plans on … Read more…
GPlates has been shortlisted for one of the 18 Australian Museum Eureka Prizes in 2023 – the Australian Research Data Commons Eureka Prize for Excellence in Research Software thanks to over 15 years of support by the AuScope National Collaborative Research Infrastructure Strategy.
Low‐temperature thermochronology is a powerful tool for constraining the thermal evolution of rocks and minerals in relation to a breadth of tectonic, geodynamic, landscape evolution, and natural resource formation processes through deep time. However, complexities inherent to these analytical techniques can make interpreting the significance of results challenging, requiring them to be placed in their … Read more…
Kimberlites are sourced from thermochemical upwellings which can transport diamonds to the surface of the crust. The majority of kimberlites preserved at the Earth’s surface erupted between 250 and 50 million years ago, and have been attributed to changes in plate velocity or mantle plumes. However, these mechanisms fail to explain the presence of strong … Read more…
11 July 2023 Tectonic changes alter sea levels that can create breeding grounds for life Movement in the Earth’s tectonic plates indirectly triggers bursts of biodiversity in 36-million-year cycles by forcing sea levels to rise and fall, new research has shown. Dinosaur Stampede exhibit at Dinosaur Canyon, located in Queensland’s Winton Formation which was formed … Read more…
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…
PyGPlates is an open-source Python library to visualize and edit plate tectonic reconstructions created using GPlates. The Python API affords a greater level of flexibility than GPlates to interrogate plate reconstructions and integrate with other Python workflows. GPlately was created to accelerate spatio-temporal data analysis leveraging pyGPlates and PlateTectonicTools within a simplified Python interface. This … Read more…
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…
We have just released GPlately1.0 as a conda package. GPlately was created to accelerate spatio-temporal data analysis leveraging pyGPlates and PlateTectonicTools within a simplified Python interface. GPlately is a python package that enables the reconstruction of data through deep geologic time (points, lines, polygons and rasters), the interrogation of plate kinematic information (plate velocities, rates of subduction … Read more…
The Royal Society of NSW Clarke Memorial Open Lecture on Wednesday 5 April 2023 will be delivered by Dietmar Müller on “Reconstructing ancient oceans, sea-level fluctuations, the deep carbon cycle and biodiversity”. Venue: Gallery Room, State Library of NSW, Shakespeare Place Abstract This presentation is a journey through geological time, reconstructing ancient oceans that have … Read more…
We evaluate four mantle convection models that use tectonic reconstructions to specify kinematic boundary conditions to explore the development of the lower mantle large low shear velocity provinces (LLSVP) structures and their relationship with mantle plumes. Evolution of mantle plumes in our spherical models is broadly consistent with observations including the number of plumes generated … Read more…
Our capability to reconstruct past landscapes and the processes that shape them underpins our understanding of paleo-Earth. We take advantage of a global-scale landscape evolution model assimilating paleoelevation and paleoclimate reconstructions over the past 100 million years. This model provides continuous quantifications of metrics critical to the understanding of the Earth system, from global physiography … Read more…
The evolving mosaic of tectonic plates across the surface of the Earth sets boundary conditions for the evolution of biotic and abiotic processes and helps shape the dynamics of its interior. Reconstructing plate tectonics back through time allows scientists from a range of disciplines (such as palaeobiology, palaeoclimate, geodynamics and seismology) to investigate Earth evolution … Read more…
In the context of continental extension, transient compressional episodes (stress inversion) and phases of uplift (depth inversion) are commonly recorded with no corresponding change in plate motion. Changes in gravitational potential energy during the rifting process have been invoked as a possible source of compressional stresses, but their magnitude, timing, and relationship with depth inversions … Read more…
Dynamic subsidence and uplift of plates are often explained by the vertical motion of density anomalies in the mantle. Such models predict surface vertical motion rates of less than 100 m Myr−1 at long-wavelengths with a timespan of tens of Myr. However, during periods of relative sea-level stability, some of the phases of vertical motion … Read more…
Colombian geologist Sara Polanco uses a computer-game-like river modelling software to understand the processes that make and connect river networks, hopefully providing the tools to help better manage water resources in the future. “That software allows me to simulate how rivers change under different scenarios,” Polanco says, “In a sense, it is like a computer game where … Read more…
We studied the microstructural and textural modification of columnar calcite naturally deformed at increasing shear strain. The studied marbles were sampled from different structural levels of the Basal Unit of the Cycladic Massif on Evia Island, Greece. The marbles have experienced high pressure metamorphism at peak temperatures around 350 °C. The long axes of the columnar calcite grains and their c-axes were … Read more…
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…
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…
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…
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…