ENPE842
Applied Geostatistics for Reservoir Characterization
ED 612, 202310
Instructor: Dr. G. Zhao
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Course Lecturing Arrangement
Working Strategy is described under the following 4 levels (4Ls):
Basic Level (BL): Review fundamental terms, concepts and knowledge in various aspects of petroleum
reservoir engineering, currently by using the textbook. Any other proper books can be potentially used as
well in future.
Technical Level (TL): Review/Study the technical application methods in detail for volumetrics, material
balance, well testing, well logging, reservoir simulation, production decline, history matching and reservoir
performance prediction. Basically what you have learned from PSE courses.
Advanced Level (AL): Data management with Golden software – Surfer, Applied Geostatistics - Stanford
Geostatistical Modeling Software (SGeMS), Well Testing and Production decline analysis (Briefly through
Application of Deconvolution theorem and superposition), Kappa software for testing data analysis - Ecrin,
CMG for further advanced reservoir evaluation and characterization study.
Practical Level (PL): within this course work through a final project to get familiar with workflow. In reality
one learns through field practice in dealing with field reservoir engineering complexity.
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So, our Textbook is pretty much at the BL/TL
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So, our Textbook is pretty much at the BL/TL
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How do you Characterize something like?
Image copy from
http://teamnonublog.blogspot.com/2017/03/the
-elephant-in-room.html
Using a strategy such as, the proverbial blind man strategy to probe an elephant.
* This situation is in fact better than reservoir engineering and reservoir
characterization, since one can actually touch the elephant!
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The Blind Men and the Elephant
John Godfrey Saxe (1816-1887)
It was six men of Indostan
To learning much inclined,
Who went to see the Elephant
(Though all of them were blind),
That each by observation
Might satisfy his mind.
The First approached the Elephant,
And happening to fall
Against his broad and sturdy side,
At once began to bawl:
"God bless me! but the Elephant
Is very like a WALL!"
The Second, feeling of the tusk,
Cried, "Ho, what have we here,
So very round and smooth and sharp?
To me 'tis mighty clear
This wonder of an Elephant
Is very like a SPEAR!"
The Third approached the animal,
And happening to take
The squirming trunk within his
hands,
Thus boldly up and spake:
"I see," quoth he, "the Elephant
Is very like a SNAKE!"
The Fourth reached out an eager
hand,
And felt about the knee
"What most this wondrous beast is
like
Is mighty plain," quoth he:
"'Tis clear enough the Elephant
Is very like a TREE!"
The Fifth, who chanced to touch the
ear,
Said: "E'en the blindest man
Can tell what this resembles most;
Deny the fact who can,
This marvel of an Elephant
Is very like a FAN!"
The Sixth no sooner had begun
About the beast to grope,
Than seizing on the swinging tail
That fell within his scope,
"I see," quoth he, "the Elephant
Is very like a ROPE!"
And so these men of Indostan
Disputed loud and long,
Each in his own opinion
Exceeding stiff and strong,
Though each was partly in the right,
And all were in the wrong!
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How do you Characterize something?
Such as: this proverbial Blind man and elephant
Image copy
from internet
• None of them got a clear picture of the animal
• However, as a whole, put all information together, one may come up with a better concept
about what an “elephant” looks like, the same thing happen to us, as reservoir engineers!
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What is Geostatistics and Reservoir Characterization?
• Determine the size, shape, and property distribution of a reservoir.
--- We cannot see, cannot touch the reservoir, thus we are blind engineers to a reservoir. But really?!
• Based on incomplete set of data, reservoir engineers need to answer:
 What is the original oil in place
 What is the remaining recoverable oil in place?
 Where is the remaining oil located and under what conditions(pressure & saturation)
 How can the remaining oil be recovered?
 What is the drive mechanism of the reservoir?
 What is needed to optimize recovery?
 Can oil rates and reserves be economically increased?
• Geostatistics and Reservoir Characterization are integrated, iterative process that must contend with
uncertainty, dealing with uncertainty is one of the main challenges in reservoir engineering.
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What are geostatistics and reservoir characterization?
• Assumption needs to be made and periodically checked to evaluate how it fits
the actual data.
• Both static data (such as facies, permeability, porosity) and dynamic data (such
as pressure & production rates) must be integratively studied and analyzed
together to reduce uncertainty, and to cross-validate reservoir and fluid
parameters (lab data offer valuable information to meet this purpose)
• Each reservoir is unique and each engineer must fashion a characterization
from for the dataset & methods available as best as he or she can.
• Solving the puzzle of reservoir characterization is a creative act and one of the
most satisfying in our engineering experience.
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Software Sources:
Golden Surfer: Download from
http://www.goldensoftware.com/student
SGeMS: can download from:
http://sgems.sourceforge.net/
Kappa Engineering
https://www.kappaeng.com/
CMG
https://www.cmgl.ca/
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Way to Succeed:
• Join the class regularly as scheduled and following the technical
content offered by instructor
• Understand the theoretical background of the Geostatistical
Methodologies
• Complete the assignment and final project on time
• Learn to use softwares, such as SGeMS, CMG, Kappa
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Other information sources:
SPE OnePetro
short course
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