run the resistivity logs in cased hole wells

Hi,

Can we run the resistivity logs in cased hole wells, and what are the parameters influence the measurement; and could we trust into values of resistivity.

Thanks in advance.


my email is: rtld312@yahoo.fr

i think SCHL has been trying to sell the CHFR (cased hole formation resistivity) for some time, i have never seen the result of it anyway.

other things that can 'predict' or estimate the LLD reading behind casing is the PNL tools. i think both the SCHL and HLS have their RST/RMT tool to do just that...

Hi spherical,
many thanks.


Laid

Generally, you cannot run resistivity logs inside casing, because of the conductive steel casing.
As Spherical pointed out, Schlumberger has a tool called CHFR (Case Hole Formation Resistivity) which can be run in cased hole. It is a stationary measurement tool and records the formation resistivity behind the casing.
The pulsed neutron logging tool such as the RST (Schlumberger) and RMT (Halliburton) measures the Sigma (neutron capture cross section) of the formation (rock and fluids). This can be used to estimate the saturation of formation water in the rock.

Ko ko kyi, from your experience how do they perform? The chfr/rst/rmt?

Personally, I have not used the CHFR tool. As I do not have any personal experience with CHFR logs, I cannot comment on the performance of the CHFR tool.
We have run many pulsed neutron logs, such as RST (Schlumberger) and RPM (from Baker Hughes). We have had successes with these tools when they are run inside a single casing, but not so reliable results when run inside completions with multiple strings.

Hi,

Many thanks kokoyi & spherical for sharing your experience.

Laid