Most new ocean floor is made when undersea volcanic activity splits the crust and molten rock fills the gaps. However some new ocean floor develops when rock stretches along gently inclined tectonic faults called detachment faults.
The new research suggests the significance of this stretching process as a way of creating new sea floor has been underestimated. No active examples of these detachment faults had been seen - until now.
Co-author Prof Joe Cann, from the University of Leeds said: “Detachment faults appear to break one of the most fundamental rules of geology. After all of the theorising about them, trying to explain how they might exist, it is immensely exciting to discover active faults emerging from the sea floor.”
Detachment faults are characterised by their curved surfaces, like corrugated iron roofs, and by swarms of tiny earthquakes. Because the distinctive shape of the faults as they emerge, it was possible to show that along 80 kilometres of the Mid-Atlantic Ridge all of the new crust along one side was being formed through a chain of linked detachment faults each at a different stage of evolution, which was highly unexpected. After a while, each fault becomes inactive, and is replaced by a newly-emerging fault.
Co-author Deborah Smith, of Woods Hole Oceanographic Institution, said: “In our area, detachment faulting is the most important way in which new ocean floor is constructed. The initial signs are that detachment faulting is far commoner along many hundreds of kilometres of the Mid-Atlantic Ridge than anyone had supposed before. These observations shed a new light on the evolution of the ocean floor.”
About 3 square kilometres of new ocean floor is created around the world every year. With sea floor comprising two thirds of the Earth’s crust, this new work is invaluable in helping us understand how the Earth’s surface is formed.
Widespread active detachment faulting and core complex formation near 13 degrees N on the Mid-Atlantic Ridge by Deborah Smith of Woods Hole Oceanographic Institution, USA, Johnson Cann of the University of Leeds, UK and Javier Escartin of Marine Geosciences Group, France, was published yesterday (27 July) in Nature.
Vanessa Bridge | alfa
Climate change weakens Walker circulation
20.10.2017 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen
Shallow soils promote savannas in South America
20.10.2017 | Senckenberg Forschungsinstitut und Naturmuseen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Interdisciplinary Research
20.10.2017 | Materials Sciences
20.10.2017 | Earth Sciences