well logging geology earth science

2. MODULAR DENSITY
TOOL(MDT)

3. MDT:-
MDT is the tool through which we can test the formation and
measure the formation pressure, temperature and get the pure
reservoir fluid and water samples.
MAIN COMPONENTS OF AN MDT TOOL :-
Formation Pressure Gauges
Formation Resistivity Gauges
Pump Out
Live Fluid Analyzer
Sample Chamber

4. Crystal quartz gauge

5. There are few main points which should be keep in mind before Using
the MDT.
1- Select the depth points for formation pressure.
2- Select at least three (3) pressure points in one bed.
3-Pressure points should fall in oil/gas zones and water bearing zone.
4- Select the oil/gas sample point, which should be clean and try to get it
from top of the reservoir.
5-Also select a point for water sample in water bearing zone.

6. MDT Operation:-
MDT operation you should consider the points which are given below:-
1- MDT Gauges should be calibrated.
2- Check the tool zero position.
3- MDT packer should be set correctly.
4- Formation pressure should be less than mud pressure.
5- Don’t stay longer at any point.
6- Take care before taking the formation sample.

7. MDT INTERPRETATION:-
For interpretation you have to make a graph between the formation pressure
and depth.
• When you plot the formation pressure against the depth you will get the
density values of which are given as under:
Oil, Gas and Water has different values.
1-Gas = 0.55 g/cc
2-Oil = 0.88 g/cc
3-Water = 1.0 g/cc
• These are density values of different fluids. Where your gradient changes you
can mark the Gas-Oil contact, Gas-Water contact, Oil-Water contact.
• In low permeable carbonates dual packer MDT is useful.

8. Interpretation Services for MDT
Well site
Formation pressure
Down hole fluid analysis: fluid color and
composition analysis, viscosity, density,
florescence, resistivity, and pH
Hydrocarbon composition (C1, C2, C3–C5,
and C6)
Gas/oil ratio (GOR)
Standard Interpretation
Grading of pressure
Excess pressure analysis
Advanced Interpretation Multi-well pressure analysis

9. Diagram of MDT tool (center), with photographs showing dual packer module (left)
and single probe module (right).

10. THANKS!!!