Subsea sampling is an activity which is rapidly gaining acceptance in the oil and gas industry, for applications in subsea field developments in deep and ultradeep water. Starting from the first ROV operated subsea sampling experiences 15 years ago, the industry is now seeing more and more operators including sampling systems in their subsea field architectures.

The paper describes the key trends of the subsea oil and gas industry which are also the main drivers behind the development of a subsea sampling system and of the corresponding subsea sampling services. It then covers the most common applications enabled by subsea sampling, which span over the full producing life of a subsea field, and interest all the main domains involved with underwater oil and gas production:

• Production Monitoring
• Flow Assurance
• Subsea Processing
• Reservoir Modeling
• Reservoir Management
• Well Intervention
• Enhanced Oil Recovery.

The benefits brought by the implementation of the Subsea Sampling capability in a given field are then discussed:

• Improved accuracy of the production measurements, which lead to accurate definition of produced hydrocarbons, corresponding royalties and allocation of production among partners
• Improved recovery rates due to more accurate Reservoir Modeling and improved decision making process for Reservoir Management
• Reduced loss of production due to improved flow assurance strategy and inhibitor injection strategy
• Reduced intervention costs and improved effectiveness, due to optimized frequency and optimized treatments (scale squeeze, inhibitors injection, produced water reduction)

The paper then describes how subsea sampling has evolved through the year and how it can be implemented, safely, cost effectively and without altering in any way the ongoing production. Different possibilities for integration of a subsea sampling interface into the subsea hardware are described.