SoylentNews is people
SoylentNews
Scientists Discover Volcanoes on Venus Are Still Active
A new study identified 37 recently active volcanic structures on Venus. The study provides some of the best evidence yet that Venus is still a geologically active planet. A research paper on the work, which was conducted by researchers at the University of Maryland and the Institute of Geophysics at ETH Zurich, Switzerland, was published in the journal Nature Geoscience on July 20, 2020.
[...] Scientists have known for some time that Venus has a younger surface than planets like Mars and Mercury, which have cold interiors. Evidence of a warm interior and geologic activity dots the surface of the planet in the form of ring-like structures known as coronae, which form when plumes of hot material deep inside the planet rise through the mantle layer and crust. This is similar to the way mantle plumes formed the volcanic Hawaiian Islands.
But it was thought that the coronae on Venus were probably signs of ancient activity, and that Venus had cooled enough to slow geological activity in the planet's interior and harden the crust so much that any warm material from deep inside would not be able to puncture through. In addition, the exact processes by which mantle plumes formed coronae on Venus and the reasons for variation among coronae have been matters for debate.
Also at EarthSky.
Corona structures driven by plume–lithosphere interactions and evidence for ongoing plume activity on Venus (DOI: 10.1038/s41561-020-0606-1) (DX)
Journal Reference:
Anna J. P. Gülcher, Taras V. Gerya, Laurent G. J. Montési, et al. Corona structures driven by plume–lithosphere interactions and evidence for ongoing plume activity on Venus, Nature Geoscience (DOI: 10.1038/s41561-020-0606-1)
(Score: 1) by khallow on Tuesday July 21 2020, @01:47PM (2 children)
"Has had". It's not tidally locked with the Sun, but it's pretty close. That means tidal forces are no longer providing that level of heating. It's also a bit smaller than Earth meaning both less heating from radioactive material and formation (the collisions that would have formed Venus), and greater radiating of that heat to atmosphere and space.
That is an important factor, but it also means the atmosphere can absorb much more heat from the surface. So some decline in temperature gradient, but a much larger heat capacity. I think it balances out.
(Score: 2) by PartTimeZombie on Tuesday July 21 2020, @10:36PM (1 child)
I'm sure I read somewhere about the water in Earth's lithosphere acting as a lubricant which helps to keep our tectonic plates moving.
Or something like that.
(Score: 1) by khallow on Tuesday July 21 2020, @11:06PM
I believe that is correct. Other volatiles like carbon and sulfur dioxide also supposedly work that way. A key part of it is that supposedly these volatiles reduce the melting temperature of the rock, making it less viscous at any temperature near or above the melting point. That less viscous rock in turn provides the lubrication.