we have quite a bit of life that thrives just under the surface… within nooks and crannies of dust particles… inside Chernobyl… in ocean volcanic vents…
i think mycelia are the only thing that can live off of just raw rock though (the vanguards of life)
but, spores are pretty small and everywhere…
personally i think we should get over looking for life on mars and seed it with whatever has the best chances…
a deep valley has a thicker atmosphere and more shade from the sun, btw…