Sure,
the finding of abundant olivine dust on the surface of Mars really only guves us the last billion years or so of climate, but it does so in a globally-integrated and restrive way - you cannot have had more than trivial local water (even the odd damp morning dew or melting frost), over this whole billion years, so ideas of milder climate cycles with gullies trickling with meltwater are difficult to sustain.
What is a little more constraining is the deeper bedrock exposures of olivine, e.g. in V.M. - here we have terrains around 3 Ga in age with an extensive regional olivine layer at 4 km subsurface depth. This says that the cryosphere has been >4km thick at the EQUATOR for >3 Ga.
If you read my website, you'll see that I have long made the link between submarine canyon geometry and that of the Martian channels - and use this to infer a similarity of genetic process. I'm not the first to make this connection -Nummedahl was perhaps the first to publish this idea.
However, one cannot plausibly infer submarine turbidite flows for the channels on Mars - otherwise the Oceans would have lapped too high and swamped everything, destroying the crater record. Instead, you have to find another type of density flow. I used a gas-supported one.
Do you have any good alternatives?
Space/Science » in reply to re: Simple Counter Questions
Olivine postdates wet Mars?
The whole thread (51 posts)
- Will Life Be Found On Mars? Your opinions and guesses:
- Dear friends, thanks for the vigorous discussion. I love it when I start a thread and there are many differing responses. David. (n/t)
- hmmm
- The Martian Race by Greg Benford
- For former life, I'd bet on Venus first
- 50-50
- Yes
- Well
- I follow Lovelock: Equilibrium = Death
- Possibly extremophiles under the surface
- re: Will Life Be Found On Mars? Your opinions and guesses: