So much of our knowledge about geology comes from the study of Earth-bound processes, which we have observed, first-hand, for centuries. By comparison, how much first-hand knowledge do we have of exo-geological processes ?
We venture onto another world, and find the same geological structures.
Does this mean, absolutely, that the same geological processes necessarily resulted in the same observations, on an alien world ?
How much exo-geology do we infer from familiar Earthly processes, when coming up with explanations for observations on different worlds ? Are we even fully conscious of these when developing exo-environmental theories?
How many permutations of the variables involved, might result in the same observations, but by different means ? Given the exact same initial environmental conditions that has resulted in water inclusions in a volcanic Earth rock, can we confidently predict that these will also result in the same water inclusions inside a moon rock ?
Come to think of it, putting aside the question of how did these water inclusions get into the moon-rock crystals …. do we really know where the Earth's water came from, why there is so much of it, and why it has stayed here ?
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