Page 58 - Drilling Technology in Nontechnical Language

Chapter 3 – DRILLING A LAND EXPLORATION WELL 49

Drilling notes for each hole section

In each hole section, there may be particular problems that might be
expected. A good program would anticipate these problems and offer
strategies to avoid or minimize the impact of the problem. It should also
offer strategies to recover from the hazard or problem if it were to occur.

The following also may be included:
▪ Required drilling practices. It may be that specific operational

procedures must be used, and these can be detailed here.
▪ Recommended operational sequence of events. This gives an
anticipated chronological sequence of events, such as drill to a

certain depth, run (specified) electrical logs, and run casing. It
includes:
▫ Drill bit recommendations
▫ Bottomhole assembly recommendations (as explained below)

▫ Any special requirements

Drilling uid requirements

The circulating fluid has a huge impact on almost all aspects of drilling,
logging, cementing, and cost. The drilling fluid (mud) must be carefully

designed to keep the wellbore stable (a stable hole stays at the same diameter
of the bit that drilled it) and also to perform many other functions. The mud
for each section will have specific chemical and physical characteristics

that must be kept as designed.

Directional information

Everything that defines the path that the wellbore should follow must
be known. Diagrams showing the well profile from the side (called the

vertical section) and from above (called the plan view) must be included.
As the well is drilled, the actual wellbore position is marked on the same
chart, so a glance at the chart shows how closely the actual well path
follows the planned well path.

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