... Abstract Topside interrogation for distributed acoustic sensing (DAS) of subsea wells for vertical seismic profiling (VSP), well integrity, and sand control requires optical engineering solutions to compensate for the insertion losses and back reflections accumulated through umbilicals...

... to use conventional approach and equipment, e.g. drilling equipment, BOP and marine riser/workover riser. This practice is a conventional and reliable method to P&A subsea wells. The introduction of RLWI vessels to P&A subsea wells are unconventional and there are uncertainties of the reliability...

... Abstract Deployment of dedicated riserless well intervention (RLWI) vessels to perform a number of light-weight plug and abandonment (P&A) operations on subsea wells (also called pre-P&A) is now being used systematically in the North Sea as an alternative to modular offshore drilling...

... operation to continue despite the presence of CaCO3scale. The paper will also discuss the equipment and Riserless Light Well Intervention (RLWI) method to derive valuable lessons learned for future operations. Method The operation took place in the British shelf of the North Sea. A subsea well...

...Introduction The combination of increasing global energy demand ( Fig. 1 ), known reserves being depleted, and the offshore locations of new oil and gas discoveries is pushing drilling and production into deeper and deeper waters. Abstract The number of subsea wells has increased...