A new study by Jacobs University Bremen, in close cooperation with the University of Bonn and the University of Cologne, shows that 2,700 million years ago vast landmasses already existed on earth. The research results have now been published in science journal Geology. (DOI: 10.1130/G35014.1).
The Temagami Iron Formation: an archive of 2,700-million-year-old seawater
Copyright: M. Bau / Jacobs University Bremen
The question when vast landmasses rose above sea-level remains an issue of debate within the science community. Computer simulations, for example, suggested that 2,500 million years ago only 3% of the Earth’s surface area was dry.
A new geochemical approach to address this issue has now been developed by Michael Bau, Professor of Geosciences at Jacobs University Bremen, his Ph.D. student Sebastian Viehmann and collaborators Dr. Elis Hoffmann (University of Bonn) and Prof. Carsten Münker (University of Cologne), who studied the distribution of rare trace elements and the isotopic composition of hafnium (Hf) and neodymium (Nd) in ancient seawater.
Analyzing unusually pure iron-rich sedimentary rocks (banded iron-formation, BIF) from Temagami, Canada, which are an archive of 2,700-million-year-old seawater, the researchers were able to extend the Hf isotope record of seawater back in time to the Early Earth’s ocean.
The Temagami BIF shows that 2,700 million years ago, seawater was anomalously enriched in the radiogenic Hf-176 isotope, whereas its Nd isotopic composition was normal. This reveals that the same decoupling of Hf and Nd isotopes, which is observed in the modern ocean, did already persist 2,700 million years ago.
Prof. Bau explains: “Seawater that is enriched in Hf-176 is produced when rocks at the Earth’s surface are subjected to terrestrial erosion and weathering. The observed decoupling of Hf and Nd isotopes recorded in the Temagami BIF indicates that already 2,700 million years ago, large areas of dry land were emerged above sea-level and exposed to wind and rain.”
The results of this study are now published in scientific journal Geology.Decoupled Hf-Nd isotopes in Neoarchean seawater reveal weathering of emerged continents
Authors: Sebastian Viehmann, J. Elis Hoffmann, Carsten Münker, Michael BauContact:
Andrea Daschner | idw
Researchers find higher than expected carbon emissions from inland waterways
25.05.2016 | Washington State University
Rutgers scientists help create world's largest coral gene database
24.05.2016 | Rutgers University
Permanent magnets are very important for technologies of the future like electromobility and renewable energy, and rare earth elements (REE) are necessary for their manufacture. The Fraunhofer Institute for Mechanics of Materials IWM in Freiburg, Germany, has now succeeded in identifying promising approaches and materials for new permanent magnets through use of an in-house simulation process based on high-throughput screening (HTS). The team was able to improve magnetic properties this way and at the same time replaced REE with elements that are less expensive and readily available. The results were published in the online technical journal “Scientific Reports”.
The starting point for IWM researchers Wolfgang Körner, Georg Krugel, and Christian Elsässer was a neodymium-iron-nitrogen compound based on a type of...
In the Beyond EUV project, the Fraunhofer Institutes for Laser Technology ILT in Aachen and for Applied Optics and Precision Engineering IOF in Jena are developing key technologies for the manufacture of a new generation of microchips using EUV radiation at a wavelength of 6.7 nm. The resulting structures are barely thicker than single atoms, and they make it possible to produce extremely integrated circuits for such items as wearables or mind-controlled prosthetic limbs.
In 1965 Gordon Moore formulated the law that came to be named after him, which states that the complexity of integrated circuits doubles every one to two...
Characterization of high-quality material reveals important details relevant to next generation nanoelectronic devices
Quantum mechanics is the field of physics governing the behavior of things on atomic scales, where things work very differently from our everyday world.
When current comes in discrete packages: Viennese scientists unravel the quantum properties of the carbon material graphene
In 2010 the Nobel Prize in physics was awarded for the discovery of the exceptional material graphene, which consists of a single layer of carbon atoms...
The trend-forward world of display technology relies on innovative materials and novel approaches to steadily advance the visual experience, for example through higher pixel densities, better contrast, larger formats or user-friendler design. Fraunhofer ISC’s newly developed materials for optics and electronics now broaden the application potential of next generation displays. Learn about lower cost-effective wet-chemical printing procedures and the new materials at the Fraunhofer ISC booth # 1021 in North Hall D during the SID International Symposium on Information Display held from 22 to 27 May 2016 at San Francisco’s Moscone Center.
24.05.2016 | Event News
20.05.2016 | Event News
19.05.2016 | Event News
25.05.2016 | Trade Fair News
25.05.2016 | Life Sciences
25.05.2016 | Power and Electrical Engineering