Mmm. Brown's Gas is an oxy-hydrogen mix, essentially it's unburnt hydrogen plus sufficient oxygen to burn much or all of it. When ignited, it turns to water (vapor.) Wouldn't trying to process more than an apparent 4 billion years worth of radiation tend to ignite it and burn it off before it could do even a tiny percentage of the job? Not to mention the heat produced by plate tectonics working thousands of miles per hour and so forth.
I'm also wondering what you mean about Oklo. That's a natural reactor that formed in Gabon a couple of billion years ago. Are you saying Somebody did that one first in order to perfect their uhm, oxidation-prevention technology before they proceeded to oh whatever, flood the whole planet and then clean it up so it left no trace, for example?
Don't let me discourage you, I'm looking forward to experimental results involving you walking through live reactors protected by dehydrated water.
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