Distributed acoustic sensing of subsea wells
Citation
Andreas Ellmauthaler, Brian C. Seabrook, Glenn A. Wilson, John Maida, Jeff Bush, Michel LeBlanc, James Dupree, and Mauricio Uribe, (2020). Distributed acoustic sensing of subsea wells. The Leading Edge, 39(11), 801-807. https://doi.org/10.1190/tle39110801.1
Keywords
- Distributed Acoustic Sensing (DAS)
- Subsea wells
- Optical fiber
- Optical circulator
- Rayleigh backscattering
- Vertical seismic profiling (VSP)
- Dry-tree
- Tie-back distance
- Acoustic bandwidth
- Backscattered light
- Optical losses
- Subsea infrastructure
- Enhanced backscatter fiber
- Hydrogen ingression (or darkening)
- Optical flying lead (OFL)
- Subsea tree
- Umbilical
- Optical feedthrough system (OFS)
- Signal-to-noise ratio (S/N)
- Sampling rate
- Gauge length
- Remote circulator assembly
- Erbium-doped fiber amplifier (EDFA)
- Tubing-encapsulated fiber (TEF)
Brief
This article introduces a novel Distributed Acoustic Sensing (DAS) solution utilizing a subsea fiber topology with a remote optical circulator to achieve dry-tree-equivalent acoustic sensing performance in subsea wells by overcoming limitations related to optical losses and long tie-back distances.
Summary
Topside Distributed Acoustic Sensing (DAS) in subsea wells faces challenges like reduced acoustic bandwidth and optical losses. This article presents a new DAS solution utilizing a subsea fiber topology with a remote optical circulator deployed at the subsea tree. This design limits the sensing fiber to the downhole section, achieving dry-tree-equivalent acoustic sampling frequencies and eliminating back reflections from subsea connectors. Combined with enhanced backscatter fiber, this system delivers high-quality DAS data for applications like seismic profiling and reservoir diagnostics, as validated by laboratory and field trials
Origin: https://sci.bban.top/pdf/10.1190/tle39110801.1.pdf#