(Source: Petroleum Engineering Handbook Volume V)
Here is the checklist of data acquisition for cased hole logs.
- Ask why do you need the data:
- Measure changes in the well after completion like high water cut, corrosions, high GOR, saturation change?
- Ask how do you get the data:
- Which tool do you use? RST, PLT, Corrosion logs?
- Will it work? Tool limitation and borehole condition.
- Is it suitable to meet your objective? Understand tool physics and their deliverables.
- Ask when you want to get the data?
- Baseline – earlier the better, before change takes place.
- During production or injection (Flowing pass)
- During shut in/no flow
- Communicate with field about operations - the flow rates, shut in time and duration of cased hole logs.
- How many passes?
- Sigma: two passes for repeatability
- PLT: up and down passes, at two or three different speed during flowing, and one up and down pass at one speed for spinner calibration. Additional stationary passes if required to confirm spinner response.
- Corrosions: Main pass with repeat pass over certain interval for repeatability
- Water Flow Log – Stations pass
- QC log data.
- Interpret log data.
- Compare with other logs, nearby wells and reservoir models.
Did I miss any steps?
1. SPE Petroleum Engineering Handbook, Volume V