User blog comment:Unownshipper/Metallurgists Wanted: Rapture's Natural Resources/@comment-75.36.142.53-20140810162926

"Resources found at the depths of the ocean" - which is around 3000+ feet around Raptures location. Rapture is (?) up in that volcano crater nearer the surface (base at 600 feet might be sufficient - tops of 400 foot tall buildings wouldnt be taken off by passing icebergs - some parts up closer to surface on the seamount highpoints to have access to air (for industrial processes) and some sunlight)

Deep Sea production is expensive (high pressure suits pre-ADAM would be required)

McClendon may have made alot of sea-work robots and remote controlled machinery (prefab city work for example)

Submarines would have to travel to distant locations for rarer materials (nearest pertoleum  is north of iceland about 400+ miles away)