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Seabed Logging (SBL) – A Promising Tool when Exploring in Frontier Basins. NOT AN OFFICIAL UNCTAD RECORD. Erik Gundersen, Tage Røsten, Jan Vollset & John Reidar Granli Statoil ASA. Talk outline. SBL - What is it, and how does it work? Calibration case example
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Seabed Logging (SBL) – A Promising Tool when Exploring in Frontier Basins NOT AN OFFICIAL UNCTAD RECORD Erik Gundersen, Tage Røsten, Jan Vollset & John Reidar Granli Statoil ASA
Talk outline • SBL - What is it, and how does it work? • Calibration case example • Exploration case example • Statoil´s experience
History of SBL*)Highlights 1997 R&D project in Statoil 2000 Statoil did a successful field test (West Africa) 2002 emgs (ElectroMagnetic GeoServices) established 2004 emgs was sold to Warburg Pincus Inc. Since 2003 Statoil uses SBL in exploration on regular basis *) Generally also referenced to as Marine Controlled Source ElectroMagnetics (MCSEM)
Ideation: From wireline resistivity logging to SBL SBL is a method to remotely detect high resistivity subsurface volumes using EM signals in marine environments rair~ ∞ r~ 0.5 – 3.0 m r~ 10 – 200 m rwater~ 0.3 m r~ 1 m r~ 0.5 – 1.5 m
SBL principles(i)Water saturated reservoir (with low resistivity) H2O No refraction of waves to the receivers
SBL principles (ii) HC saturated reservoir (with high resistivity) HC Refraction of waves to the receivers
3D seismic data 2D seismic data SBL validate/delineate validate/delineate Seismic data and SBL aqcuisition identification/exploratory
Fast track processing: 1-2 days Acquisition: 1-3 weeks Resistivity depth imaging: 2-3 weeks Integrated interpretation with geological and geophysical data Workflow and time frames Feasibility work and survey planning: 1-2 weeks
Statoil and SBL SBL is a proven technology for remote detection of HC saturated reservoirs for cost effective exploration • Statoil has invented, and is a leader within, this technology • Statoil has acquired SBL data in different deep and shallow water areas • 22 surveys over 35 targets • 12 drilled targets (post-well and pre-well) • … with very encouraging results • Statoil works systematically to improve processing and interpretation techniques
Acknowledgements We thank: • Troll License Group • Statoil • emgs