This study is the first to conclusively relate geochemical differences in surface lava rocks from both chains to differences in their deep mantle sources, 2,800 kilometres below the Earth’s surface, at the core-mantle boundary.
Underwater action scene of robotic mechanical arm on the JASON2 submersible collecting a pillow lava sample from Mauna Loa volcano at 10,000 feet below sea level during 2002 expedition. Photo taken by camera on JASON2 Credit: M. Garcia and J.M. Rhodes).
"We now know that by studying oceanic island lavas we can approach the composition of the Earth's mantle, which represents 80 per cent of the Earth's volume and is obviously not directly accessible," says Dominique Weis, Canada Research Chair in the Geochemistry of the Earth’s Mantle and Director of UBC’s Pacific Centre for Isotopic and Geochemical Research.
"It also implies that mantle plumes indeed bring material from the deep mantle to the surface and are a crucial means of heat and material transport to the surface."
The results of this study also suggest that a recent dramatic increase in Hawaiian volcanism, as expressed by the existence of the Hawaiian islands and the giant Mauna Loa and Mauna Kea volcanoes (which are higher than Mount Everest when measured from their underwater base) is related to a shift in the composition and structure of the source region of the Hawaiian mantle plume. Thus, this work shows, for the first time, that the chemistry of hotspot lavas is a novel and elegant probe of deep earth evolution.
Weis and UBC colleagues Mark Jellinek and James Scoates made the connection by fingerprinting samples of Hawaiian island lavas--generated over the course of five million years--by isotopic analyses. The research included collecting 120 new samples from Mauna Loa--"the largest volcano on Earth" emphasizes co-author and University of Massachusetts professor Michael Rhodes.
"Hawaiian volcanoes are the best studied in the world and yet we are continuing to make fundamental discoveries about how they work," according to co-author and University of Hawaii volcanologist Michael Garcia.
The next steps for the researchers will be to study the entire length of the Hawaiian chain (which provides lava samples ranging in age from five to 42 million years old) as well as other key oceanic islands to assess if the two trends can be traced further back in time and to strengthen the relationship between lavas and the composition of the deep mantle.
Chris Balma | EurekAlert!
Sea ice extent sinks to record lows at both poles
23.03.2017 | NASA/Goddard Space Flight Center
Less radiation in inner Van Allen belt than previously believed
21.03.2017 | DOE/Los Alamos National Laboratory
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
23.03.2017 | Life Sciences
23.03.2017 | Power and Electrical Engineering
23.03.2017 | Earth Sciences