Page 32 - Practical Well Planning and Drilling Manual

Section 1 revised 11/00/bc 1/17/01 2:55 PM Page 8

[ ] Well Design
1.1.2

with a regulatory body. It may also be possible to talk to the people
responsible for wells in the area. They often have detailed personal
knowledge of the wells drilled.
Hole section summaries. There is a good method of summarizing
large quantities of offset data in a way that is meaningful “at a glance.”
These documents can be updated as further wells are drilled. They are
invaluable later on for those 2 a.m. calls from the rig when problems
are encountered, as well as for updating the programs of subsequent
wells. The wellsite drilling supervisor can use them for reference if
attached to the well plan. They are also useful to include in end of well
reports. They are called hole section summaries because each sheet sum-
marizes one hole section for all wells drilled at that time.
A hole section summary is created for each hole section.
Information from each offset well is shown side by side in columns,
which are divided in rows by formation. Comparisons can be quickly
made in the same formations between several wells. On the left-hand
side the formation is described to show lithologies and problem areas,
with notes on compressive strengths (derived from sonic logs) and
other relevant information.
For each well there are three adjacent columns. The left column
shows depths of formation tops and thicknesses. The center column
shows a representation of each bit run, including BHAs used, bit
gradings, etc. An arrow shows each bit run and information regard-
ing the run is written in. The right-hand column shows data on para-
meters, rate of penetration (ROP), mud properties, and short notes
where needed.
Below each well section is a box to include comments on
casing/cement jobs, overgauge hole from logs, and any problems log-
ging or other worthwhile comments.
It is very easy to use these summaries to refer to while planning.
It is recommended that you make these from the information avail-
able to you before you do anything else on the well plan. These sum-
maries should not be swamped with too much detail or they lose
their utility. You can easily use them to identify areas needing further
study. (See Fig. 1—1.)

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