This article is based on
Pocket Pal" by E. R. (Ross) Crain, P.Eng., first
published in 1987, and updated annually until 2016.
webpage version, updated 2021, is the copyrighted intellectual
property of the author.
Do not copy or distribute in any form without explicit
EXERCISES FOR THIS COURSE
The 20 or so
web pages in this Chapter of Crain's Petrophysical Handbook cover
much the same content as
Crain's Practical Quantitative Log
Analysis for Conventional Reservoirs - a Video
Course for CEOs, geoscientists, engineers, and
petrophysicists looking to improve their oil-finding skills.
This includes basic definitions, the analysis model, Crain's
Rules for visual log analysis, common mathematical algorithms
with usage rules and recommended parameters. The only thing
missing is the dulcet tones of my voice and the video slide
show. See the menu at the right for the complete topic index for
To benefit from this course, you should practice with some real
data, as well as read the text. Here are three Exercises to
check out your skill set:
1: CLEAN and SHALY SANDS with OIL and WATER
DOLOMITIC SAND with OIL and ANHYDRITE CAP
DOLOMITE REEF with GAS, OIL, and WATER
Each exercise has raw data and answer depth plots, a visual
analysis, well history, core data, and other useful info typical
of what might be found in your well files. A spreadsheet
analysis using "META/KWIK" is provided for each exercise (see
next Section on this webpage).
Other case histories
that can be used for practice are in
A kit containing LAS log
data files for these and 7 other examples, including full-size raw
data and answer plots, core data listings, and other useful stuff,
can be purchased HERE so you can test your
existing software or any user defined equations you have created
from the models described in this Chapter.
Spreadsheet software provides the fastest method for quantitative petrophysical
analysis of conventional oil and gas reservoirs. By converting "Crain's Rules" into
mathematical form, and adding more sophisticated algorithms for
water saturation, permeability, productivity, and reserves, we can
perform a complete analysis in less than half an hour.
Download this spreadsheet and test your skill. Right click
and choose "Save Target As" for safe downloads.
Metric Units Version
QUICKLOOK SPREADSHEET RESULTS for EXERCISE 1
The best tool for quicklook log analysis is a spreadsheet.
Pick parameters and log data from the raw logs shown above. When
data entry is complete, the answers are instantly available.
META/KWIK data and results for Exercise 1