It's been almost ten years since I was down there last, but I seem to recall that most of the rock i saw along the way looked like some form of sandstone. There are some big sandstone formations in the area (I think Painted Rock is one) but a little googling tells me there is also basalt and granite.
No big deal. Rock I.D. is a tricky business and without being able to get a closer look, I can't be sure either.
That first pic looks like granitic rock to me because of the color and the way it is weathering.
The surface looks really nubbly/coarse - probably a result of large crystals of different minerals disintegrating at different rates.
The second pic shows layered strata in the distance - so if the rocks in the foreground correlate, it's a good bet they are also sedimentary - and the color looks right. Too far away to speculate further.
Of course I could be wrong
