It was interesting to read a paper on Creep. I am working as logging engineer since last 5 years. I have worked with two major companies but none of them taught me about creep.
If my understanding is not wrong then the author of paper has suggested three solutions to avoid creep problem. But I am not sure how can service company implement them
1) Compare downlog to uplog of CCL near perforation zone at normal logging speed. If there is a difference then it means that wireline is stretching during uplog and, consequently, the creep occurs when winch is stopped for perforation. But this just an indication of creep happening. It doesn't tell how much creep will occur.
2) "Another simple way to determine whether creep might be a problem is to stop the winch abruptly and see if the casing collar locator continues to “rattle” for a half a second or more." Whatever CCL I have run there is no way to know if CCL is rattling. Even if CCL is stationary, it keeps on giving basic noise. Again, this just an indication of creep happening. It doesn't tell how much creep will occur.
3) "to perforate while moving". It is very dangerous and split delay of a second can cause engineer shooting way off depth.
I suggest someone should do a study to determine how much creep occurs in how much time. let say, the perforation is done immediately after winch is stopped, in that case the creep might be negligible.
Another suggestion would be to go down atleast 3 collars below perforation zone and record up CCL as slowly as possible to minimize stretch and this will minimize creep in result when winch is stopped. But I find very difficult to get CCL below 20-25 ft/min logging speed even if gain and threshold are properly adjusted
The only solution that I think with my little knowledge is to use
GR for correlation as GR can be recorded as slow as possible. The less logging speed will cause less stretch in wireline for a given well and, consequently, less creep when wireline stopped for perforation.