Open Hole
Auxiliary
Acoustic
Nuclear
Imaging
MRIL
Pressure and Sampling
Resistivity
DLL™ Dual Laterolog Service
Halliburton's proven DLL™ dual laterolog service provides a reliable means of measuring formation resistivity in conductive borehole fluids and/or where large contrasts exist between the formation and mud resistivities. The DLL service operates by focusing currents into the formation to produce a deep resistivity measurement (LLd) and a shallow resistivity measurement (LLs). The MSFL™ micro- spherically focused log is usually run in combination to provide a third shallow resistivity measurement. Together, these three measurements provide the resistivity profile around the borehole and permit the computation of Rt in
presence of invasion.
Applications
- Provides accurate, high resolution shallow (LLs) and deep (LLd) resistivity measurements in high Rt/Rm conditions (>100) or when formation resistivity exceeds the limits for conventional induction tools (> 2,000 ohm-m)
- Quantitative assessment of Sw
- When run with the MSFL log, provides estimates of Rt, Rxo, and diameter of invasion
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Quantitative assessment of moveable water saturations (Sxo) and moveable hydrocarbon volumes
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Acquires improved formation resistivity measurements in saline borehole fluids and in high Rt/Rm (>100) contrast logging conditions or when formation resistivity exceeds the limits of induction tools (>2000 ohm-m)
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Provides MSFL measurements to help delineate thin beds and provide estimates of Rxo
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Offers qualitative indication of permeable zones and estimating invasion diameters (when run with the MSFL tool)
Features
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Rugged sonde construction and state-of-the-art electronics provide for accurate measurements of formation resistivity up to 40,000 ohm-m
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Dual electrode arrays and an automatic current-focusing technique
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The fundamental vertical resolution is 24 for both measurements which facilitates reservoir description of thinly bedded formations
