Abstract
I would like to start my discussion by giving you a brief history of offshore platform development since its beginning in 1947 in the Gulf of Mexico. I will then discuss the important preliminary steps which must be undertaken before a decision is made to develop an offshore field after a discovery has been made. I refer specifically to such items as the establishment of environmental criteria, water depth, foundation conditions, number of wells required, number of drilling rigs, production equipment needed, etc. The many different types of structures will then be reviewed, along with reasons for choosing one type over another for a specific discovery. Deep water (> 1000′) development will be discussed, with an emphasis on the special problems associated, and the structures anticipated for such development. I will then discuss briefly the improvements needed in our technology as we go into deeper water and give my opinion as to where we can be in the next ten years, given the opportunity.
Though some drilling had taken place in offshore waters from timber trestles and in inland waters and marshlands before World War II, the first steel platform on which drilling took place was installed in 1947 in the Gulf of Mexico in about 20 feet of water. Through the 50′s, offshore development was concentrated in water depths less than 200′. During the 1960′s, development began in the southern North Sea area in about 100′ of water, a much more hostile environment than the Gulf of Mexico. During this time also, ice-resistant structures were successfully installed in 100′ of water in Alaska.
The 400′ water depth, considered to be a barrier for a while because of anticipated problems with dynamic response, about which the industry knew very little before the early 70′s, was exceeded in the mid 70′s. By 1981, five structures had been successfully installed in water depths exceeding 600′ in the Gulf of Mexico, the deepest of which is in 1025 feet (Figure 1). Several huge platforms have been installed in greater than 500′ of water in the North Sea, and Brazil is presently developing fields with platforms in excess of 400′. The Far East will soon have two platforms in over 400′ of water--one offshore Japan and one offshore Australia.
