Evolution of Mantle Plumes and Lower Mantle Structure in Numerical Models Using Tectonic Reconstructions as Boundary Conditions

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…

EarthByte Seminar Series: Dr. Luke Daly

Join us for an exciting talk by Luke Daly, a planetary geoscientist at the University of Glasgow, as he takes us on a journey through the geological history of a Martian volcano. Using correlative microscopy, Luke has been able to uncover the complex geological history of a group of Martian meteorites known as the Nakhlites, and has used this information to predict the geomorphology of the landscape around the launch crater.

In this talk, Luke will share his insights into the evolution of Mars and the Solar System as a whole, and how his research is informing remote sensing exploration to finally locate the source of the Nakhlite meteorites on Mars.

The talk will take place on March 15th at 11:00 am AEDT, in Madsen Building Room 331, School of Geosciences, University of Sydney and will be live-streamed via Zoom for those who are unable to attend in person. This is an excellent opportunity to learn from Luke and gain insights into the mysteries of our Solar System.

To register for the talk, please visit https://www.eventbrite.com.au/e/earthbyte-seminar-series-tickets-565834575447?keep_tld=1 

We look forward to seeing you there! For more information, see the details below. See you there!

Read more…

Share

Science: Hundred million years of landscape dynamics from catchment to global scale

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…

Nature Reviews Earth and Environment: Deconstructing plate tectonic reconstructions

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…

Geology: The role of surface processes in basin inversion and breakup unconformity

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…

Terra Nova: Brief immersion of southern Australia by change in relative plate speed

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…

Software Is Unlocking The Mystery Of Why Rivers Change

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…

EarthByte Seminar Series: Dr. Samuel C Boone

EarthByte Seminar Series presents the first talk of this year by Dr. Samuel C Boone from the University of Melbourne, titled “THERMOCHRONOLOGICAL INSIGHTS INTO CONTINENTAL BREAKUP PROCESSES.” The seminar will be held in the Madsen Building Room 449 (Conference Room) from 11 am (AEDT)  Wednesday, 18th January. You are also welcome to join us live via Zoom (link: https://uni-sydney.zoom.us/j/86426471159). For more information on the seminar, see below:

Read more…

Share

EarthByte seminar series: Nicole Januszczak

This week brings the final EarthByte seminar of the year, featuring Nicole Januszczak of BHP, titled “Exploration at BHP: Putting mineral systems into action.” The seminar will be held in the Madsen Building Room 331 at 11am-12pm this Wednesday 14th December, and will also streamed live via Zoom (link: https://uni-sydney.zoom.us/j/82037433636). For more information on the seminar, see below:

Read more…

Share

J. Struct. Geol.: Microstructural and textural modification of columnar calcite under increasing shear strain (Evia Island, Greece)

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…

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

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

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

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

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

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

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

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…

EarthByte seminar series: Ben Fulcher

The next EarthByte seminar will be held at 11am–12pm on Wednesday 16th November in Madsen Seminar Room 331 at the University of Sydney. This week we will be hearing from Ben Fulcher from the Dynamics and Neural Systems Group within the School of Physics at the University of Sydney, discussing his work on “Quantifying patterns in time series.” As usual, the seminar will be streamed live over Zoom at the following link: https://uni-sydney.zoom.us/j/82037433636.

More details are below:

Quantifying patterns in time series

Read more…

Share

EOS: Billion-year rewind tracks supercontinents and mantle structures

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…

EarthByte seminar series: Nick Mortimer

The next installment of the EarthByte seminar series will be held at 11am–12pm next Wednesday 5th October, featuring Nick Mortimer from GNS Science in New Zealand. The seminar will be held in the Madsen Building Rm 449 at the University of Sydney, and streamed live on Zoom at this link: https://uni-sydney.zoom.us/j/82037433636.

Further details on the talk are below:

Read more…

Share

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…

Welcome to two new PhD students — Satyam Pratap Singh and Tom New

EarthByte globe icon

Welcome to two new PhD students who have joined the EarthByte Group. Satyam Pratap Singh has joined the Stellar project working on reconstructions of palaeogeography through time and will be jointly supervised by Maria Seton, Sabin Zahirovic and Nicky Wright. Tom New has joined a recently funded ARC Discovery Project on plate-plume interactions and will … 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…

Environmental stability on Earth allowed marine biodiversity to flourish

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

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

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…

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

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…

PyBacktrack 1.4 released

PyBacktrack 1.4 is now available, and adds support for generating paleobathymetry grids from submerged present-day crust. PyBacktrack is available as a Python package and a Docker image. Installation instructions can be found online in the pyBacktrack documentation. Changes since version 1.3: Can now generate paleobathymetry grids: Submerged oceanic and continental present-day crust is backtracked and … Read more…