University of Aberdeen, Scotland, UK - Evolution of land plants changed composition of Earth's crust, study finds

Title:

Evolution of land plants changed composition of Earth's crust, study finds

 

Published:

University of Aberdeen, 30 August 2022

https://www.abdn.ac.uk/news/16300/

 

From the article:

A new study involving an international team of researchers has found that the evolution of land plants caused a sudden shift in the composition of Earth's continents.

 

ALSO SEE

 

Spencer, C.J., Davies, N.S., Gernon, T.M. [et al.]. Composition of continental crust altered by the emergence of land plants. Nature Geoscience, 29 August 2022. 

https://doi.org/10.1038/s41561-022-00995-2

 

The University of Sydney, Australia (May 2022) - How plate tectonics has maintained Earth's 'Goldilocks' climate

Title:

How plate tectonics has maintained Earth's 'Goldilocks' climate 

 

Published:

The University of Sydney, 26 May 2022

https://www.sydney.edu.au/news-opinion/news/2022/05/26/how-plate-tectonics-have-maintained-earth-s--goldilocks--climate.html

 

From the article:

Not hothouse, nor icehouse: when tectonic plates move at a moderate speed - not too fast or slow - Earth remains habitable, new University of Sydney research finds.

 

ALSO SEE

 

Müller, R.D., Mather, B., Dutkiewicz, A. et al. Evolution of Earth’s tectonic carbon conveyor belt. Nature 605, 629–639 (2022). https://doi.org/10.1038/s41586-022-04420-x

Abstract:

Concealed deep beneath the oceans is a carbon conveyor belt, propelled by plate tectonics. Our understanding of its modern functioning is underpinned by direct observations, but its variability through time has been poorly quantified. Here we reconstruct oceanic plate carbon reservoirs and track the fate of subducted carbon using thermodynamic modelling. In the Mesozoic era, 250 to 66 million years ago, plate tectonic processes had a pivotal role in driving climate change. Triassic–Jurassic period cooling correlates with a reduction in solid Earth outgassing, whereas Cretaceous period greenhouse conditions can be linked to a doubling in outgassing, driven by high-speed plate tectonics. The associated ‘carbon subduction superflux’ into the subcontinental mantle may have sparked North American diamond formation. In the Cenozoic era, continental collisions slowed seafloor spreading, reducing tectonically driven outgassing, while deep-sea carbonate sediments emerged as the Earth’s largest carbon sink. Subduction and devolatilization of this reservoir beneath volcanic arcs led to a Cenozoic increase in carbon outgassing, surpassing mid-ocean ridges as the dominant source of carbon emissions 20 million years ago. An increase in solid Earth carbon emissions during Cenozoic cooling requires an increase in continental silicate weathering flux to draw down atmospheric carbon dioxide, challenging previous views and providing boundary conditions for future carbon cycle models.

Implications for megathrust earthquakes and tsunamis from seismic gaps south of Java Indonesia [Scholarly Article - Nature, 17 September 2020]

Title:

Implications for megathrust earthquakes and tsunamis from seismic gaps south of Java Indonesia

 

Authors:

S. Widiyantoro, E. Gunawan, A. Muhari, N. Rawlinson, J. Mori, N. R. Hanifa, S. Susilo, P. Supendi, H. A. Shiddiqi, A. D. Nugraha & H. E. Putra

 

Published:

Nature, 17 September 2020

https://www.nature.com/articles/s41598-020-72142-z

 

Abstract:

Relocation of earthquakes recorded by the agency for meteorology, climatology and geophysics (BMKG) in Indonesia and inversions of global positioning system (GPS) data reveal clear seismic gaps to the south of the island of Java. These gaps may be related to potential sources of future megathrust earthquakes in the region. To assess the expected inundation hazard, tsunami modeling was conducted based on several scenarios involving large tsunamigenic earthquakes generated by ruptures along segments of the megathrust south of Java. The worst-case scenario, in which the two megathrust segments spanning Java rupture simultaneously, shows that tsunami heights can reach ~ 20 m and ~ 12 m on the south coast of West and East Java, respectively, with an average maximum height of 4.5 m along the entire south coast of Java. These results support recent calls for a strengthening of the existing Indonesian Tsunami Early Warning System (InaTEWS), especially in Java, the most densely populated island in Indonesia.