The typical life cycle of the development of an oil or gas subsea field.

Subsea field development is a long and complicated procedure that begins with the primary survey and ends with the last reservoir recovery.

Initial stage

Initially, mapping and reconnaissance are conducted by exploration geologists and geophysicists. They ultimately delineate the development area’s geology based on the data gathered from old wells, seismic analysis, and any other information that is available. The initial issues at this stage concern the following aspects:

  • Structure of the basin and the subregional features (i.e., fault and/or fold traps for hydrocarbons);
  • The stratigraphy (i.e., whether the reservoir rocks exhibit porosity and permeability);
  • The burial history of the basin (i.e., whether the source rocks have been buried sufficiently for hydrocarbon generation).

By addressing these concerns, investigators may identify and select parts of the larger area for further study and may ultimately generate a prospect evaluation.

Reservoir description

After the initial investigations, the reservoir description phase begins, which involves drilling delineation wells and perhaps conducting 3D seismic analyses. This new information allows reservoir engineers and geologists to calculate the volume of oil and/or gas that is present in the reservoir.

Field layout/installation

Then it is time to ascertain the optimum subsea field layout and pipeline route; the production facilities will also be selected based on field layout and installation considerations.

Production

After all well and equipment testing, the field begins to produce oil and gas. However, as more and more oil and gas are transported to the host structure from the reservoir, the reservoir pressure will decrease, and need to employ enhanced recovery to keep the production being transported from the reservoir.

The development of a field architecture and system integration and interfacing are the most important parts of a field development project. When defining a field architecture, the following issues should be considered:

  • Deepwater or shallow-water development;
  • Dry tree or wet tree;
  • Stand-alone or tie-back development;
  • Subsea processing;
  • Artificial lift methods;
  • Facility configurations (i.e., template, well cluster, satellite wells,manifolds).

Sea also

References

  • Subsea Engineering Handbook by Yong Bai and Qiang Bai, Publication Date: January 27, 2012 | ISBN-10: 0123978041 | ISBN-13: 978-0123978042 | Edition: 1