Latest News and Announcements:
Several studies published by EarthByte and their collaborators have received international publicity in recent months. Dr Sabin Zahirovic and colleagues have constrained the "tectonic speed limits" from plate reconstructions and their work was highlighted by the Huffington Post, where the story and animation below have had 90,000+ hits! The study was received international coverage elsewhere as summarised here.
Understanding how the Hawaii-Emperor bend formed
Deciphering the past movements of tectonic plates on Earth is important for understanding how the deep Earth evolved through time. One particular mystery is the bend in the Hawaiian-Emperor seamount chain, as this chain represents a trace of the Pacific plate moving over the Hawaiian hotspot. There are two alternative causes proposed for this 47 million-year-old bend: a large change in the Pacific plate's motion, due to a reorganization of the tectonic plates in the Pacific basin; or a change in the motion of the Hawaiian hotspot driven by a change in mantle flow. To explore the plate reorganization scenario, EarthByte's Nicky Wright and collaborators, in a paper in Geology, used data preserved on the Pacific seafloor to revise its spreading history between 66 and 33 million years ago. The approach allowed them to better determine the timing of any changes in the seafloor spreading history, with 95% confidence estimates. They found that only a small change in Pacific seafloor spreading occurred around 47 million years ago, implying that there was no major change in the motion of the Pacific plate. This provides independent evidence that the Hawaiian-Emperor bend is largely due to a change in the motion of the Hawaiian hotspot. These observations highlight the very active role of mantle convection in driving the formation of volcanic islands. That a major change in mantle flow may have followed the onset of subduction of the Pacific Plate around 50 million years ago is also supported by recent computer simulations of coupled plate motion and mantle flow in the Pacific hemisphere by Maria Seton et al. (Geophysical Research Letters). They show that complete Izanagi plate subduction and margin-wide slab detachment induced a major change in sub-Pacific mantle flow, from dominantly southward before 60 Ma to north-northeastward after 50 Ma.
Dr Maria Seton and Dr Simon Williams from the School of Geosciences and colleagues from GNS Science and the Geological Survey of New Caledonia were awarded ship time on Australia's new, state-of-the-art research vessel, the RV Investigator. The supplementary voyage, with Dr Seton as Chief Scientist, will investigate the continuity of Australian terranes into Zealandia through the Lord Howe Rise via targeted dredging of the Fairway Ridge. The voyage will also present an opportunity to travel back to "Sandy Island" where rock samples will be recovered in order to determine the age and origin of the ridge underlying this phantom island.
Professor Dietmar Müller and collaborators at the Scripps Institute of Oceanography, the European Space Agency and the USA Laboratory for Satellite Altimetry have released an improved marine gravity model from CryoSat-2 and Jason-1 satellite data. Their paper has been published in Science and is receiving a lot of attention from international media! Read more about the new marine gravity model here or view the map interactively in GPlates Portal.
Published: 3 Oct. 2014
Nature publication: Spreading continents kick-started plate tectonics
EarthByte researchers Assoc. Professor Patrice Rey and Dr Nico Flament, together with collaborator Prof. Nicolas Coltice from the AUGURY project in France have a new theory about the initiation of subduction, which suggests that spreading of early continental crust may have created gravitational instability which kick-started this plate-tectonic process. Watch an animation of the model results here!
The paper, which can be found here, was
discussed in the Nature editorial and received extensive media attention across international news sites including these stories: USA News, Technobahn, Lyon Capitale, The Conversation, Business Standard, Bioportfolio, EurekAlert! Popular Mechanics, Daily News, Vancouver Verdesi, Scitech Daily, Yahoo! News, Science Newsline, Universite Lyon and was discussed in these Blogs: I F*%ing Love Science! and Asian Scientist.
View the Nature journal metrics
Published: 22 Sept. 2014
Basin GENESIS hub - Sedimentary Basin Modelling Research Funded
Assoc. Professor Patrice Rey and Professor Dietmar Müller, have been awarded new research funding, of $5.4 million over five years from the Australian Research Council (ARC) and industry partners, for the Basin GENESIS Hub that will use computational modelling to understand the evolution of sedimentary basins. The project will harness big data sets and super-computer resources to model the interaction between earth's surface processes and deep Earth processes in 'five dimensions'.
The funding was announced by the Federal Minister for Education and is funded through the Industry Transformation Research Hub program the main partners are the University of Melbourne Geodynamics group, Curtin University's Petroleum Group, CSIRO Earth Science and Resource Engineering, National ICT Australia (NICTA), Geoscience Australia, the California Institute of Technology, and five national and international industry partners.Read more on this story or see all other Media and Publicity here
Illustration of the use of modelling techniques to understand basin evolution, courtesy of Luke Mondy, PhD candidate
Published: 13 June, 2014
In the News: What is it really like under the Indian Ocean?
Dr Simon Williams and EarthByte collaborator, Jo Whittaker, have written a piece for The Conversation, regarding the mysteries surrounding the Indian Ocean seafloor. They highlight the limited ship-track bathymetry data available in the Eastern Indian Ocean and discuss the importance of marine surveys and geophysical research in understanding the ocean structure and tectonic processes.Read the story here
This figure from their story shows the difference in resolution between ship-track bathymetry and satellite-derived bathymetry
Published: 17 June, 2014
Recent Research Highlight: Rift migration and Asymmetry
Dr Sascha Brune and others (2014) have published a new study "Rift migration
explains continental margin asymmetry and crustal hyper-extension" in Nature Communications.
They use high-resolution computer models and geological data from the South Atlantic margins and demonstrate that rifts are capable of moving sideways over hundreds of kilometres. During rift migration, the crust on one side of the rift is weakened by hot upwelling material in Earth's mantle, whereas the other side is slightly stronger as the crust there is colder.
Read more here
Download the paper and supplementary information.