Low-Cost Recovery System for Oil, Gas, and Thermal Seepage

Describes an innovative method for constructing large, thin-shell, highly reinforced concrete pontoons, domes, and risers for installation over thermal vents and hydrocarbon seeps. Cost projections based on marine structures previously built by the method and tested for long-term durability, show savings of more than fifty percent in labor and materials over their counterparts in steel or conventional concrete. Building takes place in floating formwork at or near the site without the need for shipyard facilities and with no size limit on monolithic contruction. The method can also substantially reduce the cost of an OTEC cold water tube and platform. Possible applications to seabed mining, smelting, and transportation are mentioned