Geology (ceresology?) question.

Base camp for my Ceres expedition is near an unusual geological feature, an ice crevasse under the floor of a ravine. Does this description seem reasonably plausible, or at least a generally right flavour of bullshit? Do the diagrams look OK?

I should preface it by saying that for scenario purposes Ceres has a partially liquid interior (somewhat like theory predicts for the real Ceres), with ammonia dissolved in the water acting as anti-freeze.

( base camp )

Sound OK? Too dry and technical? All comments welcomed.