Mars outcrops breccia instead of conglomerate? Water not needed?
NASA is claiming that it has found conglomerates on Mars based on some deposits that have been found by the new Curiosity Mars rover. They are using this claim to go on to assert that water must have flowed across the planet, despite the current atmospheric conditions precluding water.
Couldn't those outcrops be more plausibly consist of breccia whose exposed clasts have been rounded remove their original angular morphology so the exposed examples resemble pebbles?
The breccias could plausibly have been deposited during volcanic eruption or be due to impact shock from ancient asteroid strikes (Mars is close to the asteroid belt, and there is ample evidence of volcanism on Mars). Hence there is no need to claim a watery past for Mars.
See this article for example (including images):
http://www.nasa.gov/mission_pages/msl/news/msl20120927.html