Crisman Annual Report 2009 - Harold Vance Department of ...

An Advisory System for Selecting Drilling Technologies and Methods in Tight Gas
Reservoirs
Objectives
The main objective of this research project is to
develop a computer program dedicated to applying
the drilling technologies and methods selection for
drilling tight gas sandstone formations that have
been documented as best practices in the petroleum
literature. We have created an advisory module
for tight gas that is part of a general Drilling &
Completion Advisor for unconventional formations.
This Drilling & Completion Advisory Module, along
two other programs called BASIN (basin analogy)
and PRISE (resource evaluation) is part of the
UGR (unconventional gas resources) Advisor under
development at Texas A&M by a team of graduate
students and professors.
Approach
To complete the Drilling Advisory Module for tight
gas reservoirs, we have identified and reviewed
relevant data in worldwide literature on tight gas
reservoirs with a strong emphasis on the latest
drilling technologies, such as: casing drilling,
underbalanced drilling, managed pressure drilling,
horizontal drilling, directional S-shaped drilling (well
clusters) and coiled tubing drilling. We have analyzed
under which critical parameters one technology
has been preferred or is currently being applied in
comparison with other drilling techniques. Further,
we have extracted key criteria and have developed
decision charts, which mimic the thinking process of
an expert. We have written Visual Basic programs
using Microsoft Visual Studio implementing all the
decisions charts created during this research. Finally,
we will test and validate the Drilling Advisory Module
with U.S. tight gas real cases.
Accomplishments
Our results have led to the following accomplishments:
» A drilling advisory system has been designed and
programmed for a Windows O.S. environment in
order to capture the industry best drilling practices
from tight gas reservoirs.
» The advisory system has been divided into
several sub-modules to guide the user through
the multiple steps to make decision selecting
drilling technologies and methods to drill tight gas
reservoirs. Each of the sub-modules deals with
a specific topic (well data, drilling parameters,
drilling time, drilling cost, ranking). Each dataset
can be loaded or saved in a text file for analysis
or post-processing using other software (Microsoft
Excel).
» The advisory system is designed with a user-friendly
interface, to help select efficient and successful
drilling technologies and drilling methods.
» The drilling advisory system outputs more than
one feasible solution for a given well or field.
» The logic behind the advisory system, mainly based
on decision charts developed by collecting relevant
data from the petroleum engineering literature
and discussions with industry drilling experts, is a
good approach to mimic expert decision-making.
» This project has illustrated several examples that
happen to match the current industry drilling best
practices or anticipate upcoming drilling practices
in the studied area. These simulations showed that
the drilling advisory system could deliver similar
recommendations in comparison with a team of
experienced drilling experts.
» Drilling time, drilling cost estimation and ranking
technologies, and methods sub-modules provide
the user with an extended decision making tool
when several solutions are feasible.
» The drilling advisory system has been designed
and programmed for easy integration within the
Unconventional Gas Resources Advisor. It can be
further upgraded with other drilling sub-modules
or new drilling technologies when they are mature
on the market.
Project Information
1.1.12 Developing an Expert System for Well Completions
in Tight Gas Reservoirs Worldwide
Related Publications
Pilisi, N.: 2009. An Advisory System for Selecting Drilling
Technologies and Methods in Tight Gas Reservoirs. MS
thesis, Texas A&M U., College Station, Texas.
Contacts
Stephen A. Holditch
979.845.2255
holditch@tamu.edu
Catalin Teodoriu
catalin.teodoriu@pe.tamu.edu
Nicolas Pilisi
CRISMAN INSTITUTE
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Crisman Annual Report 2009