New study explains previous observations of ocean water flowing through the seafloor from one seamount to another
Vast quantities of ocean water circulate through the seafloor, flowing through the volcanic rock of the upper oceanic crust. A new study by scientists at UC Santa Cruz, published June 26 in Nature Communications, explains what drives this global process and how the flow is sustained.
About 25 percent of the heat that flows out of the Earth's interior is transferred to the oceans through this process, according to Andrew Fisher, professor of Earth and planetary sciences at UC Santa Cruz and coauthor of the study. Much of the fluid flow and heat transfer occurs through thousands of extinct underwater volcanoes (called seamounts) and other locations where porous volcanic rock is exposed at the seafloor.
Fisher led an international team of scientists that in the early 2000s discovered the first field site where this process could be tracked from fluid inflow to outflow, in the northeastern Pacific Ocean. In a 2003 paper published in Nature, Fisher and others reported that bottom seawater entered into one seamount, traveled horizontally through the crust, gaining heat and reacting with crustal rocks, then discharged into the ocean through another seamount more than 50 kilometers away.
'Ever since we discovered a place where these processes occur, we have been trying to understand what drives the fluid flow, what it looks like, and what determines the flow direction,' Fisher said.
For the new study, first author Dustin Winslow, a UCSC Ph.D. candidate who graduated this month, developed the first three-dimensional computer models showing how the process works. The models reveal a 'hydrothermal siphon' driven by heat loss from deep in the Earth and the flow of cold seawater down into the crust and of warmed water up out of the crust.
'Dustin's models provide the best, most realistic view of these systems to date, opening a window into a hidden realm of water, rock, and life,' Fisher said.
The models show that water tends to enter the crust ('recharge') through seamounts where fluid flow is easiest due to favorable rock properties and larger seamount size. Water tends to discharge where fluid flow is more difficult due to less favorable rock properties or smaller seamount size. This finding is consistent with field observations suggesting that smaller seamounts are favored as sites of hydrothermal discharge.
'This modeling result was surprising initially, and we had to run many simulations to convince ourselves that it made sense,' Winslow said. 'We also found that models set up to flow in the opposite direction would spontaneously flip so that discharge occurred through less transmissive seamounts. This seems to be fundamental to explaining how these systems are sustained.'
Winslow's project was funded by the U.S. National Science Foundation through a graduate fellowship and as part of the Center for Dark Energy Biosphere Investigations (C-DEBI). UCSC is a partner in C-DEBI, which is headquartered at the University of Southern California.
Tim Stephens | EurekAlert!
New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland
19.01.2017 | University of Gothenburg
Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Life Sciences
20.01.2017 | Physics and Astronomy
20.01.2017 | Materials Sciences