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Mars Volcanoes May Still Erupt
Q3vi1 writes "Space. com reports, Images from a European space probe reveal recent glacial deposits and lava flows on Mars that suggest the red planet is more active than many scientists had thought."
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Well, we have only been closely looking at mars for (in an astronomical sense) a fraction of a second. Just because there hasn't been any evidence of eruption yet doesn't really mean anything.
Mars does have a molten core, according to JPL. Strikingly similar to both earth, and venus. Interesting stuff, none the less.
Excuse me, I don't mean to impose, but I am the ocean
Mars does have a molten core.
Take a Look
Excuse me, I don't mean to impose, but I am the ocean
Actually, they look much like certain lava flows on earth. Here's the URL of a primer on vulcanism with some examples:
http://pubs.usgs.gov/gip/volc/types.html
Mars igneous rocks are mafic -- rich in iron and magnesium, low in silica and volatiles (e.g. water). Mafic magmas are low viscosity and have a better chance of reaching the surface in a liquid state. Since they are also low in water, they don't explode.
On earth, we also have big sheets of mafic lava flows -- the Deccan Traps in India, Watchung Mountains in New Jersey, Grand Mesa in Colorado just to name a few.
Venus isn't inactive it just has long periods of inactivity before enough pressure builds and a huge amount of its surface gets covered in molten lava. This is due to no water being on the planet thereby lacking the necessary lubrication for plate technonics and an active surface like us.
"I don't which is worse, that everyone has a price, or that the price is always so low"--Hobbes
"That is they are by the gas laws (which also apply to liquids and solids)"
The gas laws certainly don't apply to liquids and solids. If I double the pressure (taking atmospheric pressure into account) of a drop of water, its absolute temperature doesn't double. I can't calculate the work required to compress water using the gas laws (instead I must use the bulk modulus). If I put a blowtorch on a piece of steel its volume doesn't double (or its pressure change). Etc.
There are some fundamental assumptions used in the gas laws that don't apply to solids or liquids. Some of the assumptions include: the average intermolecular spacing is assumed to be huge so that inter-molecular forces are insignificant, the walls of the container are infinitely hard, the gas is homogenous, and the gas particles are infinitely small.