Abstract: A mobile, self-elevating, offshore production platform, for exploitation of smaller reservoirs, is provided with a liquid tight hull having a deck; a plurality of support legs, each having a gear rack and bottom footpads, which are slidably extendable through the hull; a removable jacking tower for each support leg, and, a locking means for each support leg which is engageable to the leg gear rack at any vertical position of the leg. Mineral processing equipment is pre-installed on the deck at a suitable shoreside facility. Then the platform, with legs elevated, is towed to the offshore location where minerals are to be produced. On location the legs are lowered, grounded, and then pre-loaded to desired criteria by introducing ballast water into the hull. After pre-loading the platform is deballasted and elevated to establish a desired air gap.