NMR Results Without NMR Logs

Virtual Magnetic Resonance Processing (VMRP)

VMRP is a proprietary log analysis technique that allows computation of many NMR log outputs from standard logs such as resistivity, neutron-density, sonic, etc. This can be a useful technique in the millions of cased wellbores where an actual NMR log cannot be recorded. Also it may preclude the need for running actual NMR logs in every well in a field development situation.

Case Study – Cretaceous Muddy Sand – Wattenberg Field, Colorado
Thousands of wells had been drilled and completed in this Cretaceous "Muddy Sand" section in the rockies. The NMR log revealed that the radioactive silty sand above the field pay might be productive. The operator included this sand in the completion and doubled production. The synthetic NMR result readily identifies the bypassed pay zone.

nmr cretaceous muddy sand case study

Case Study – Vicksburg Sand - South Texas

This example is of Vicksburg sand in South Texas. The Vicksburg offers challenges to formation evaluation including varying grain sizes and changing mineralogy. The analysis below features synthetic NMR results including bound fluid and perm estimates. Pay zones at 2 ohm-m are discriminated from wet zones also at 2 ohm-m (confirmed by FT and production of 8 mmcfd). Recognizing the low contrast pay zones in addition to the standard pay zones increases net pay by 3 times and doubles hydrocarbon pore-volume. The standard pay flags are on the left side in red, the new pay flags reflecting the low resistivity pay are in green. Several other low contrast pay zones were confirmed in this well and in offset wells. The volumetric results were confirmed by an NMR log in an offset well.

nmr south texas vicksburg sand case study