Like the outcrops ahead with layers! such as this hilltop and the outcrops onthis hillside.

I think the Meridiana type rocks, with spheres found in situ there at Gusev are supportive evidence of extensive, global oceans on Mars during the Noachian. The sulfates in the depths of the Valles Marineris also support this view. That guy's "...Mars was always dry" orbital formation theory is all washed up (IMHO). It only makes sense that the farther out planets have relatively more light elements. Look how much atmosphere Venus has. Earth lost most of its atmosphere, it's only a tiny fragile husk now. With a diameter of 7,926 miles, the troposphere is only about 7 miles thick, or 0.2% of the total diameter. Mars was probably something in between early Earth and Jupiter, a planet with a vast atmosphere and kilometer deep oceans- until it gradually lost its protective magnetic field since it lacks the quantity of uranium and thorium that keep Earth's core molten. I think that Mars, or the asteroid belt, were ideally situated to have the most water during planetary formation.