I imagine some form of Fischer Tropsch process. Water and carbon rocks and CO2 even under enormous heat and pressure and some types of minerals acting as catalysts. Would produce hydrocarbons as that would be more stable form at those high pressure and temperatures. The high pressure temperature energy would be converted and relieve pressure and heat from mantle/crust and turn it into chemical energy. Oil likely also helps crust float and transition more smoothly ie not huge earthquakes but smaller ones. Though I’m not a geologist so not sure on that one, I’m just thinking from purely mechanical viewpoint on how oil works in a machine.
I imagine some form of Fischer Tropsch process. Water and carbon rocks and CO2 even under enormous heat and pressure and some types of minerals acting as catalysts. Would produce hydrocarbons as that would be more stable form at those high pressure and temperatures. The high pressure temperature energy would be converted and relieve pressure and heat from mantle/crust and turn it into chemical energy. Oil likely also helps crust float and transition more smoothly ie not huge earthquakes but smaller ones. Though I’m not a geologist so not sure on that one, I’m just thinking from purely mechanical viewpoint on how oil works in a machine.