SS: Thunder Horse and Atlantis Deepwater Frontier Developments in the Gulf of Mexico: Future Challenges for Deepwater Developments
Authors: Addison Fergus , Kennelley Kevin , Botros Fikry 
Published: July 2010

Abstract
Discoveries over the past 20 years have established the Deepwater Gulf of Mexico (DW GoM) as a major hydrocarbon-producing region. The recent discoveries in Mississippi Canyon and Green Canyon areas, together with the emerging lower tertiary play in the Walker Ridge and Keathly Canyon areas signal a strong shift in field development challenges for the DW GoM. These challenges span a number of disciplines and include greatly increased drilling depths in remote areas with much higher reservoir pressures and lower permeability hydrocarbon reservoirs. Industry advances are needed in numerous technologies such as subsalt imaging, novel completion and casing designs, subsea production equipment rated in excess of 15,000 psi, subsea High Integrity Pressure Protection Systems (HIPPS), and subsea processing.
This paper provides BP's view of some of the key challenges the industry is facing, and the technologies that will be required to successfully develop the next generation of deepwater oil and gas fields in the GoM with a particular focus on those required for the lower tertiary trend. The solutions to these challenges will require cooperation among the operators, the engineering contractors and equipment suppliers working with the regulatory authorities to pave the way for the safe and reliable development of these future fields.

Introduction
Currently, the water depth record for BP's DW GoM developments exceeds 7,000 ft with reservoir pressures of 12,500 psi. As BP continues to explore and develop in deeper and more remote hydrocarbon basins worldwide, the next wave of projects, such as the recently announced Kaskida and Tiber discoveries in the lower tertiary of the GoM, are expected to have a major subsea component associated with the developments. They will require the development of very deep sub-salt reservoirs (30,000 ft +) with the compound challenges of high-pressure (15,000 psi) and heavier crude trapped in low permeability rock. In addition, these developments are located in ultradeepwater, far from existing offshore infrastructure.
In order to meet these challenges, BP will be leveraging its learnings from its earlier successes in subsea developments dating back to the first subsea development the 1970s. Since that time, BP has developed over 180 subsea wells which are currently producing approximately 800,000 bpd of oil and gas, with the number of wells expected to significantly increase over the next decade.
Since 1999, BP has successfully delivered a large number of record-breaking deepwater subsea developments worldwide. For example, BP has successfully developed the Greater Plutonio field using a Floating Production Storage and Offloading (FPSO) host off the West African coast (Figure 1). Follow-on plans are in place to develop additional subsea developments, in the ultradeepwater Block 31 (&gt;7,000 ft water depth) using modular FPSOs.
In the North Sea, the Skarv and the Schiehallion (Quad 204) harsh environment FPSO subsea developments are in various stages of development. And, BP has plans to develop a large number of subsea tie-back projects to existing facilities, including the record-breaking, 72-km Taurt gas development in Egypt.
As a result, BP has acquired unique knowledge and experience in the development and operation of world-class subsea installations under very challenging conditions. BP also has developed a keen appreciation for the engineering contractors, equipment suppliers and other technical professionals who work together with BP's own experienced staff, creating a team that is capable of meeting future deepwater technical challenges.