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March 17th, 2020 All Day



Members: $100 & Non-members: $150

To be held at Devon Energy in Multipurpose Room 4

Parking directions will be emailed to participants.





George B. Asquith, Texas Tech University                                                                                                


 The course begins with a short review of the basic principles of well logging, and how these basic principles are applied to determine if a shaly sandstone is potentially hydrocarbon productive. Also included will be a review of clay mineralogy, and why the presence of clay and/or shale cause sandstones to have low resistivity which results in high water saturations.     


The first steps in shaly sandstone analysis are the determination of volume of clay/shale (Vcl), and the use Vcl to correct the reservoir’s total porosity (Ftotal) to effective porosity (Fe). Because the Vclay/shale is so important in shaly sandstone analysis multiple techniques will be presented using a variety of well logs. Then the effective porosity (Fe) will be applied to the construction of a shaly sandstone producibility plot (Q-PLOT) to determine if the shaly sandstone is a reservoir after it has been corrected for Vclay/shale. 


The final step is to determine using log data if the reservoir has effective or non-effective clay present, and what shaly sandstone model can be used to best convert total water saturation (Swtotal) to effective water saturation (Swe). Several models will be presented to determine Swe, including an EXCEL Spread Sheet of a new method to determine Vcl and Swe. A flow chart is provided with examples that will aid the participants in understanding the sequence that is used in analyzing sandstones and shaly sandstones. At conclusion ten examples will be presented that will be analyzed by the participants. Included with the notes is a detailed outline of how shaly sandstone samples should be analyzed when doing special core analysis.



 A Short Course in Shaly Sandstone Analysis

G.B. Asquith


       Basic Principles

            1. How to tell if a shaly sandstone is potentially hydrocarbon productive

            2.  Reviewing Clay mineralogy

           3.  Clay/shale effect on resistivity

  Overcoming the presence of clays in sandstones

        Evaluation Methods

  1. Determining volume of clay/shale (Vcl)
  2. Correcting total porosity to effective porosity using Vcl.
  3. Shaly Sand Producibility (Q plot)          

Correction of Total water saturation vs effective water saturation

            Shaly Sand Models

  1. Volume of clay-based models
  2. Non volume of clay-based models
  3. Thin bed-based mode

  Case Studies

            Anadarko Basin

                 Cottage Grove

                 Prue Granite Wash

            San Juan Basin

                   Pictured Cliffs Sandstone

            Permian Basin

                   Sprayberry Sandstone

                   Cherry Canyon Sandstone

                   Morrow Sandstone


Case Studies (cont.)

            Gulf of Mexico

                Plio-Pleistocene Sandstone

           Southwestern Kansas

                Chester Sandstone

            North Texas

                Tannehill Sandstone

           Rocky Mountain

                Frontier Sandstone



George B. Asquith, Ph.D.  (University of Wisconsin/Madison) is a Professor of Geosciences at Texas Tech University and a former recipient of the Pevehouse Chair in Petroleum Geology.  At Texas Tech he has served as a Director with The Center for Applied Petrophysical and Reservoir Studies. A focus of his work has been concentrated in the Anadarko, Permian and Delaware basins. Dr. Asquith received AAPG's Harrison Schmitt Award, Presidents Award, Distinguished Educator Award, and the Leverson Award. He is the recipient of the Pioneer Award from the West Texas Geological Society.  Recently, he received a Distinguished Alumni award from the University of Wisconsin Geosciences. During Dr. Asquith's career he has published numerous abstracts, papers and books including the best-selling AAPG book Basic Well Log Analysis.  In addition, he has worked for ARCO Research, Pioneer and Mesa Petroleum, Search Drilling and Alpar Resources.  Dr. Asquith teaches a variety of petroleum industry training courses including:  Unconventional Reservoirs, Shaly Sand Analysis, Old E log Analysis, Basic Well Log Analysis, Carbonate Petrophysics, and Fundamentals of Well Log Interpretation.