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!
Satellite data show severity of drought summers in 2018 and 2019
13.07.2020 | GFZ GeoForschungsZentrum Potsdam, Helmholtz Centre
NASA analyzes Tropical Cyclone Cristina's water vapor concentration
09.07.2020 | NASA/Goddard Space Flight Center
Biochemists at Martin Luther University Halle-Wittenberg (MLU) have used a standard electron cryo-microscope to achieve surprisingly good images that are on par with those taken by far more sophisticated equipment. They have succeeded in determining the structure of ferritin almost at the atomic level. Their results were published in the journal "PLOS ONE".
Electron cryo-microscopy has become increasingly important in recent years, especially in shedding light on protein structures. The developers of the new...
New insight into the spin behavior in an exotic state of matter puts us closer to next-generation spintronic devices
Aside from the deep understanding of the natural world that quantum physics theory offers, scientists worldwide are working tirelessly to bring forth a...
Kiel physics team observed extremely fast electronic changes in real time in a special material class
In physics, they are currently the subject of intensive research; in electronics, they could enable completely new functions. So-called topological materials...
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.
Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....
Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.
Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...
07.07.2020 | Event News
02.07.2020 | Event News
19.05.2020 | Event News
13.07.2020 | Physics and Astronomy
13.07.2020 | Life Sciences
13.07.2020 | Life Sciences