Dual Laterolog Service (DLL™)
| Halliburton’s proven Dual Laterolog
service provides 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 Micro-Spherically Focused Log
(MSFL) 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. |
| » DLL Service Features |
| The HRI
tool can be used in the following applications: |
- 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)
- Uses LLd, LLs, and MSFL to determine Rt and diameter of invasion of the formation and depth of invasion
- Provides MSFL measurments to help delineate thin
beds and provide estimates of
Rxo
- Offers qualitative indication of permeable zones
and estimating invasion diameters (when run with
MSFL)
|
| » DLL Service Benefits |
| The DLL
service gives operators a reliable way of measuring
formation resistivity in conductive borehole fluids
and/or where large contrasts exist between the formation
and mud resistivities. |
|
|
 |
| A DLL log
example from a carbonate-evaporite sequence showing deep
and medium laterolog curves presented along with the
shallow MSFL
log. |
|
|
| Length |
Diameter |
Maximum
Pressure |
Maximum
Temperature |
Weight |
| (ft) |
(m) |
(in) |
(mm) |
(psi) |
(Mpa) |
(°F) |
(°C) |
(lb) |
(kg) |
| 33.9 |
10.3 |
3.63 |
92.2 |
20,000 |
137.9 |
350 |
176.7 |
460 |
208.7 |
|
|
|
