From the President

Dick Merkel
EnCana

The Fall Workshop presented E. C. Thomas on clay minerals and their effect upon the electrical behavior of shaly sands was a great success. His insight and experience on the topic for both the laminated shale and dispersed clay models was intriguing and informative. We were most fortunate to have E. C. come to Golden for this presentation. There were close to 100 registrants that came from all over the world. This was good publicity for both CSM and the DWLS. The informal feedback was very favorable. When we have time to compile the results from the questionnaires filled out by the participants, we will report the findings to you.

One of the questions on the questionnaire given at the Fall Workshop concerned a topic for a potential Spring Workshop. I have to repeat from last month that "since these workshops are for the benefit of our membership, your input into the topic selection is imperative. Please call or email any of the Board members with your suggestions of both a topic and a speaker for upcoming workshops."

Vicki King has been the mainstay of the SPWLA organization for three decades. Officers come and go on an annual basis and Vicki not only has put up with this turmoil but has kept the Society moving in a positive direction over this time. In a recent call, she informed me that she has breast cancer in an advanced stage. Chemo has been started, and will be followed by surgery and radiation. I am sure that words of wisdom, sympathy, and encouragement would be welcome at: Vicki@spwla.com.

2007 Fall Workshop

Dominic Holmes
Digital Formation

Thanks to all that helped plan and to those who attended the Fall Workshop with E.C Thomas on October 19^th. From the comments I received and feedback forms, I think this was our best workshop to date.

As with previous workshops, our goal has been to lose money, and as per usual we didn't do a very good job of that.  Through a combination of costs coming in lower than expected, a significantly higher attendance (particularly of non-members), and fewer students than anticipated, we didn't lose all that much.  After all the bills were paid, we lost only $19.47.  A far cry from our goal of $2,000.

Here is the break down, out of a total of 99 registrants:

37 were members
54 were non-members
8 were students

We had a diverse group of attendees from Colorado, Texas, Oklahoma, California, Florida and Wyoming, as well as Canada, England and Malaysia!  The students came from CSM and Stanford.  So our efforts to attract attendees outside the DWLS membership were quite successful.

We may have a few of the booklets left over that we'll be selling on a first-come basis.  If you're interested, contact Stefani Whittaker (or 303-831-1515). 

"Using Core Data to Develop and Calibrate Petrophysical Models in Tight Gas Sandstone Reservoirs "

Dick Merkel
EnCana Oil & Gas (USA)

Rocky Mountain tight gas sand reservoirs typically have complex mineralogy in the reservoir rock in the form of sandstone, mica, feldspars, and carbonates. The clay component in the reservoir rock (and shales) is often some combination of illite, smectite, kaolinite, and chlorite. The measured signal from most logging tools originates from the rock matrix, which in this case is often both complex and poorly defined.

Selective coring and core analysis can be used to understand various tool log responses in order to develop and calibrate petrophysical models. However this requires rigorous planning that ranges from 1) specifying core bit and mud type, to 2) shipping, plugging and preserving core, to 3) specifying what conventional and special core analysis is to be performed. This protocol is particularly important in tight gas sand core analysis because some analysis needs to be done at native state conditions while conventional core analysis can be done at restored state (after the core is cleaned and dried). With the objective of using petrophysical models for the determination of static values such as OGIP and perforation location, as well as dynamic values like producibility (IP) and porosity/saturation changes, the type and frequency of core analysis can be specified.

With a selected logging suite and proper core analysis, evaluation of complex tight gas sandstone reservoirs can be accomplished. Examples will be shown how core analysis techniques ranging from tritiated mud, analysis at multiple net confining stresses, NMR, capillary pressure, mercury injection, XRD, and SEM can be used in the generation of an integrated petrophysical model. These models can then be tied to production logs and well test data.

About the Speaker

Dick Merkel is a Petrophysicist for EnCana Oil & Gas (USA), where he works on teams that develop reservoir models for tight gas sandstone reservoirs. Previously, Dick was a Senior Technical Consultant at Marathon Oil Company's Petroleum Technology Center in Littleton where he worked on evaluating new logging tools and technology, and developing techniques for their application in Marathon's exploration and development programs. Dick has a Ph.D. in geophysics from Penn State and is a past president of SPWLA. He is currently President of the SPWLA Foundation and of the DWLS.