Q1
I'm currently gathering information regarding chemical tracer vs logging tools that could provide the same result from other service providers as well. From my understanding, logging tools definitely have extra advantages I would say based on less monitoring, fast result and quick analysis.
Could you please advise/share:
1. what tools that suite the above requirement
2. How does the tools work/function ie require pairing Producer and Injector and how long does it require to be in the well
3. Software required to analyze the data and how long to interprete the data
A1
1. what tools that suite the above requirement
If one looks for vertical flow profile then only production logging can help assessing the profile.
In injectors one can use short-live tracers to assess the infectivity profile.
In injectors one can use short-live tracers to assess the infectivity profile.
If one looks for cross-well connectivity then there are only three teqniue to assess:
1) Pressure interference and pressure--pulse testing
2) Chemical or long-term radioactive tracers
3) Cross-well seismic
| Advantages | Disadvantages | |
|---|---|---|
| Cross-well pressure survey | Among those the pressure pulsation is the cheapest, fastest and the most accurate. | |
| Tracers | The main advantage of tracers is that they show flow connectivity rather than pressure connectivity. The radioactive tracer can be coupled with GR-loigging in receiving wells and can assess the vertical flow profile which pressure surveys can not do. | |
| Cross-well seismic | The advantage of cross-well seismic is that it can assess saturation in cross-well interval. | |
2. How does the tools work/function ie require pairing Producer and Injector and how long does it require to be in the well
3. Software required to analyze the data and how long to interprete the data
4. Lastly, estimate cost for above steps
Q2
How do you determine the location and nature of a fault (sealing or no sealing) from pulse test ?
I know we can say there is a barrier in between two wells, if we don’t get a pressure response from the pulsed well in the observation well.
How can we conclude that it is due to a barrier?
Also, how do we calculate at what distance from the generator well is the fault/barrier?
A2
Once the PCT is deciphered we get self-response and x-well pressure transient responses: as if all other wells are not interferring with a selected pair.
We call these transient pressure responses:
DTR (a drawdown or self-response)
and
CTR (a cross-well interference or cross-well response).
All TRs are easy to simulate in numerical softwares: 2D or 3D (for example Eclipse or tNavigator).
The meaning of this excercise is to adjust property distribution and barriers to decomposed DTRs/CTRs.
Since single DTR or CTR is taking very short time to calculate in 2D/3D solver we have opportunity to calibrate 2D/3D model step by step (each TR separately).
This would not be the case if we tried calibrating the 2D/3D model using original contaminated data without PCD deciphering -- the processing time will be huge and the calibration process would be highly ambiguous.
We call these exercises : 2D-express test and 3D-express test (3D is only needed for bottom water or gas cap scenarios)
We call these transient pressure responses:
DTR (a drawdown or self-response)
and
CTR (a cross-well interference or cross-well response).
All TRs are easy to simulate in numerical softwares: 2D or 3D (for example Eclipse or tNavigator).
The meaning of this excercise is to adjust property distribution and barriers to decomposed DTRs/CTRs.
Since single DTR or CTR is taking very short time to calculate in 2D/3D solver we have opportunity to calibrate 2D/3D model step by step (each TR separately).
This would not be the case if we tried calibrating the 2D/3D model using original contaminated data without PCD deciphering -- the processing time will be huge and the calibration process would be highly ambiguous.
We call these exercises : 2D-express test and 3D-express test (3D is only needed for bottom water or gas cap scenarios)