Standard Range
A613 - Spontaneous Potential / Point ResistanceA627 - 16" Normal 64" Normal
A636 - 16" Normal 64" Normal / PR
A616 - 16" Normal 64" Normal / SP/PR/ Lateral Resistivity
A602 - 16" Normal 64" Normal / SP/PR/ Gamma/Fluid Temp/CCL
A629 - 16" Normal 64" Normal / SP/PR/ Gamma
ALSO AVAILABLE
A617 - Lateral Tool
A610 - Gamma/CCL/ 16" Normal 64" Normal
A635 - Gamma/EAL/ 16" Normal 64" Normal / SP/PR
A622 - CCL/ 16" Normal 64" Normal / Lateral/Temp
The Gamma, Short Normal and Long Normal logs are recorded on one run. The SP and PR logs are acquired on a separate run.
ResistivityResistivity logs may be usefully applied in a number of areas.
In Ground-water studies, electrical resistivity logs have been regarded as vital for many years. Apart from general geological / stratigraphic information, resistivity values provide excellent information on two important hydro-geological aspects:
In sedimentary sequences (consolidated or otherwise) aquifers are usually much more resistive than aquicludes such as clay layers and shale. In igneous and carbonate sequences, secondary aquifers formed by fracturing or dissolution are often less resistive than the adjacent massive rocks.
In Coal studies, electrical resistivity logs indicate that the seam has been coked by an igneous intrusion, or has been affected by oxidation.
PR (point resistance) measurements are used to ascertain depths and thicknesses of strata.
These measurements will often clearly define the strata boundaries.The SP log measures small, naturally occurring spontaneous potential generated by electrochemical differences between differing rock types, water and drilling fluids. Occasionally there is another component called streaming potential created by fluids entering of leaving the borehole. Recognition of this is important in some engineering applications.
Gamma
The tool detects natural gamma radiation emanating from the sub-surface rocks. Gamma rays are very high frequency electromagnetic radiation and are derived from the radioactive decay of various elements. In borehole applications the most common radioactive elements are radioisotopes of potassium, thorium and uranium.
Please review A631 &A675 for complete details.
Specifications
| Model |
A613 SP/PR |
A627 16"N / 64"N |
A624 16"N/64"N/SP/PR |
| Range |
2 to -2mV/1 to 1000 ohms 2 to 10 000 ohms |
1 to 1000 ohm-m | 1 to 1000 ohm-m |
| Calibration |
Millivolt Values / Resistance Values | Resistance Values | Resistance Values |
| Units of measure |
mV & ohms | Ohm metres | Ohm meters & ohms |
| Communication |
Duplex Digital RS232 | Duplex Digital RS232 | Duplex Digital RS232 |
| Nominal Current |
N/A | 60 | 100 |
| Power at Sonde (VDC) |
N/A | 40 | 40 |
| Pressure Rating (KPg/PSI) |
21000/3000 | 21000/3000 | 21000/3000 |
| Temp Rating (Degrees C) |
0-100 | 0-60 | 0-60 |
| Diameter (mm) | 33 | 45 | 45 |
| Length (mm) | 730 | 2370 | 2370 |
| Weight (Kg) | 3.0 | 12.0 | 12.0 |
| Model |
A616 16"N/ 64"N/ SP / PR / |
A629 16"N / 64"N / SP / PR / Gamma |
A602 16"N / 64"N / SP / PR / Gamma Fluid Temp / CCL |
| Detector Sensor |
Current & 2 measure electrodes | Current & 2 measure electrodes Nal (TI) Crystal |
Current & 2 measure electrodes Nal (TI) Crystal Solid State Temperature Sensor |
| Range |
1 to 10 000 ohm-m 2 to -2 mV 1 to 1000 ohms |
1 to 1000 ohm-m 2 to -2 mV 1 to 1000 ohms Gamma N/A |
1 to 1000 ohm-m 2 to -2 mV 1 to 1000 ohms 0-70Deg C CCL N/A Gamma N/A |
| Calibration |
Resistance Values & mV values | Resistance Values & mV values | Resistance Values & mV values |
| Units of measure |
ohm meters, mV & ohms | Ohm metres | Ohm metres |
| Communication |
Duplex Digital RS232 | Duplex Digital RS232 | Duplex Digital RS232 |
| Nominal Current |
80 | 60 | 60 |
| Power at Sonde (VDC) |
40 | 40 | 40 |
| Pressure Rating (KPg/PSI) |
21000/3000 | 21000/3000 | 21000/3000 |
| Temp Rating (Degrees C) |
0-60 | 0-60 | 0-60 |
| Diameter (mm) |
45 | 45 | 45 |
| Length (mm) |
2370 | 2370 | 2370 |
| Weight (Kg) |
12.0 | 12.0 | 12.0 |
Auslog