PERMFILE52709

• Permit No: M1999002
• IBM Index Class Name: Permit File
• Doc Date: 6/18/1999
• Doc Name: OBJECTORS EXHIBITS
• Media Type: D
• Archive: No

• ~ III IIIIIIIII IIII III
~:~ ~~~ ' 6 -I~~~~ 999
Well Log Applications and Interpretation in a Brine Field
:~~ .- - -
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- ~~~James M. Bird .
Birdwell Division of - ' .
- Seismograph Sertrice Corp.
TY~Zsa, Oklahoma
The purpose of this paper is to discuss the application of wire line services that have evolved
as servants of the oil and gas industry to some of the subsurface problems generated by the solu-
tion mining of salt. This transplanting of techniques can be beneficial to both parties.
In the last 35 years, the wire line industry has proliferated its services to the extent that it
is now difficult to sensibly organize them. However, all have one thing in common. They involve
the lowering of electromechanical devices into holes in the earth on the end of electrical cables.
I further choose to divide all these services into two categories. Historically, the first and still
the most significant is the category that I will designate "Data Gathering." The second category I
designate "Action Producing."
In the firs[ category, data from the bottom of the hole is gathered for one of two reasons.
The data gathered is used to either evaluate the type and physical characteristics of the formations
uncovered by the bit, or the information is used to aid in the drilling or completion of the well.
In the Action Producing group are many different services. The most common are perforat-
ing, setting of plugs and packers, etc. Due to the pressure of time, these services will not be
discussed in [his paper. I am limiting myself to the data gathering group. In this group, I intend
to limit the discussion almost entirely to those services that our personnel have had experience
with in the salt mining field. I will discuss, briefly, the theory of operation of these particular
services. This will be followed by examples of their use and behavior in salt yells.
In the first group, the formation evaluation group, measurements of the formation are made
in either empty or fluid-filled, cased or uncased holes.
The Gamma Ray-Neutron Stack, see Fig. 1, is most used because of its ability to take
measurements in either open or cased, empty or fluid-filled holes. The Gamma Ray tool utilizes
either Geiger-Mueller or a Scintillation detector. The length of detector ranges from four to 12
inches. It is considered [o be eccentralized in the well bore. The detector measures the number
of gamma ray emissions coming mostly from three elements; potassium, thorium or uranium.
Because these elements are usually found in shale, the gamma ray log may be used quantitatively
to determine shale content of the formation being evaluated. In this way it becomes the primary.
log for determining the lithology of a well drilled for [he purpose of mining sal[.
The Neutron tool utilizes either aGeiger-Mueller or Scintillation detector. The length of
the detector ranges from four to six inches. The spacing, distance between source and detector,
will depend on the depth of investigation desired, the diameter of the well bore and the type of
fluid in the well. It usually ranges from 16 to 32 inches. Two common sources in use toda}~ are
Plutonium Beryllium and Radium Beryllium. The detector can be of the type that is sensitive to
either gamma rays or neutrons. Like the Camma Ray tool, it is considered to be eccentralized.
Quantitatively, the Neutron Log measures hydrogen content. briefly, this is accomplished by the
fast neutrons being slowed to thermal condition at a rate proportional to the hydrogen present
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