| Popis: |
This publication presents successful mapping of inter-well water saturation in a complex naturally fractured reservoir. The saturation distribution was based on a crosswell electromagnetic (EM) survey integrated with other well / reservoir data. The EM survey was deployed in a swept area of a tight carbonate reservoir in Saudi Arabia, between two horizontal wells, a water injector and a dead producer, using coil tubing conveyance. The presented EM saturation mapping located an area of potentially bypassed hydrocarbons. These findings were confirmed by a newly drilled slanted well that was landed in the inter-well area. The new well targeted an oil column bypassed by the water injection in an otherwise swept area and the well is currently on production. The EM field data were interpreted with a Gauss-Newton 3D inversion code. A resistivity model cannot be directly used for reservoir evaluation, then the subsequent step was to convert the resistivity model into a saturation volume, based on Archie’s law. The survey established a number of world firsts for the EM technology, including horizontal wells deployment, wells spacing >1.3 km, full 3D resistivity inversion and 3D water saturation mapping. |
