Sue received a B.S. in Mathematics from the University of Illinois (high honors) in 1973 and M.S. in Geology at the University of Wisconsin at Madison in 1976. She began her career at the Chevron Oil Field Research Company in a technical service group which integrated core analysis and wireline interpretation into ongoing development and exploration projects, both domestic and international. She was transferred into the Chevron USA Rocky Mountains division where she worked as a development geologist in the Thrust Belt and western Colorado. In 1981 she joined Buckhorn Petroleum (later named Harper Oil and Midcon Exploration) as an exploration geologist in the Rocky Mountain District. Sue consulted for several years before co-founding the Discovery Group.
Sue is active in many professional societies. She is a member of the American Association of Petroleum Geologists (AAPG) and the Division of Professional Affairs (DPA) and has served as Treasurer and Vice-President of the DPA. Currently, she is serving as President-Elect of the Rocky Mountain Section. Sue has served on various committees and as the Secretary of the Rocky Mountain Association of Geologists (RMAG). She has twice been the president of the Denver Well Logging Society (DWLS), as well as Secretary-Treasurer and Vice-President, and is currently serving as VP of Technology and VP of Membership. She is currently the Vice-President of Finance and Administration for the Society of Petrophysicists and Well Log Analysts (SPWLA) and has previously served SPWLA as a Regional Director. She has been Secretary of the Society of Independent Professional Earth Scientists (SIPES). She is also a member of the Society of Petroleum Engineers (SPE).
Sue is a registered Professional Geologist in Wyoming (PG 2680), Kentucky (#977), and Utah (5373597-2250), and a DPA Certified Petroleum Geologist (#3396).
After ARCO, he joined Landmark Graphics, and was a member of the PetroWorks development team, providing petrophysical expertise and was also involved in interface design, and development of documentation and training materials. When Landmark closed its Austin, Texas office, Dan joined Chevron, working in deep Gulf of Mexico and Chad, Africa projects. He also supported internal petrophysical training efforts.
Dan joined The Discovery Group in late 2006.
Since the late Cretaceous, Dan has taught the AAPG Basic Well Log Analysis course annually with Dr. George Asquith of Texas Tech University. Dan also teaches Basic Openhole Log Interpretation, a similar, but shorter course, through direct client requests.
In 2004, the AAPG published George and Dan's book, Basic Well Log Analysis, a second edition of George's 1983 similarly-named book which was one of the AAPG's all-time best selling publications.
Dan is a member of the Society of Petrophysicists and Well Log Analysts (SPWLA), American Association of Petroleum Geologists (AAPG), Society of Petroleum Engineers (SPE), Society of Exploration Geophysicists (SEG), the Rocky Mountain Association of Geologists (RMAG), and the Denver Well Logging Society (DWLS).
Dan is a Texas Registered Professional Geoscientist (#5014).
Catherine earned degrees in Geology from the University of Nebraska (B.S., 1972, with honors, M.S., 1975) and in Computer Information Systems from Regis University (B.S., 1987, summa cum laude). She worked for Amoco Production Company in Denver as an Exploration Geologist from 1975-1980 and was responsible for prospect generation in most of the Rocky Mountain Cretaceous basins. She was also in charge of source rock evaluation for frontier areas from Arizona to Alaska.
After leaving Amoco in 1980 she worked on exploration plays in the Rocky Mountains region and California at Fluor Oil and Gas from 1980 to 1981 and at Harper Oil Company form 1981-1985. At Harper, her project areas included Southeast Colorado, the southern Powder River Basin, Denver-Julesburg Basin, and southern Uinta Basin.
Since 1987 she has worked at The Discovery Group, specializing in regional stratigraphic mapping projects, shale gas basin studies, and reservoir mapping. Most of this work is done using Petra. She has aquired considerable experience in the following basins and plays:
- New Albany Shale of the Illinois Basin
- Barnett Shale in the Fort Worth, Delaware, and Arkoma Basins
- Woodford Shale in the Delaware and Arkoma Basins
- Floyd Shale, Black Warrior Basin
- Haynesville Shale of East Texas
- Niobrara oil in the DJ and Raton Basins
- Detailed stratigraphy of the Lawrence Field, Illinois Basin
- CBM mapping in the Cherokee Basin of Kansas
- Lance stratigraphy of Jonah and Pinedale Fields, western Wyoming
- Piceance and Uinta Basin stratigraphic mapping
She is a registered Professional Geologist in the State of Wyoming (PG-2904) and is a member of the American Association of Petroleum Geologists (AAPG), the Rocky Mountain Association of Geologists (RMAG) and the Denver Well Logging Society (DWLS).
Dan earned a B.A. in Geology with Honors, and a B.A. in French from the University of Wisconsin-Madison in 2006. He spent a summer in central Australia working as a research assistant and conducting his own research, and he subsequently completed his senior thesis on lower-crustal structural regimes based on that field work. He earned a M.Sc. in Geology from the Colorado School of Mines in 2014. His Master's degree work focused on Permian carbonates, phosphorites, and cherts from the Phosphoria Formation in west-central Wyoming.
Dan is a member of the American Association of Petroleum Geologists (AAPG), the Rocky Mountain Association of Geologists (RMAG), Society for Sedimentary Geology (SEPM, as well as the local RMS-SEPM chapter), the Society of Petrophysicists and Well Log Analysts (SPWLA), The Society for Organic Petrology (TSOP), and served on the Board of Directors of the Denver Well Logging Society (DWLS) in 2010-2011.
Ryan earned a B.S. in Geology and Geophysics, and a B.S. in Physical Geography from the University of Wisconsin-Madison in 2007. In 2013 he graduated with a M.S. in Geology from the University of Colorado – Boulder where he studied fluvial architecture and sequence stratigraphy of the Cretaceous Williams Fork Formation.
Ryan is a member of the American Association of Petroleum Geologists (AAPG), the Rocky Mountain Association of Geologists (RMAG), the Society for Sedimentary Geology (SEPM), and the Denver Well Logging Society (DWLS).
Stefani has been with Discovery Group for 11 years and is now a Sr. Petrophysical Engineer with specialties including log data cleanup, log normalization, reservoir characterization, log database setup and management, neural net solutions, tool theory and characterizations, water storage projects, and setting up and coding petrophysical workflows for tight gas and gas/oil shales. She has worked most on-shore basins in the U.S. as well as basins in Western Africa, Australia, India, Poland, Russia, the U.K., and U.A.E.
She is a member of AAPG, RMAG, SPE, SPWLA and DWLS. She has served a two-year term on the SPWLA board as a Regional Director and has held many roles in DWLS including Treasurer, President and currently inventories and mails all the on-line extra course material orders.
January 17, 1953 - October 26, 2016
Bob Cluff was a geologist and petrophysicist with nearly 40 years experience in oil and gas exploration, development, and research. His principal areas of expertise were petrophysics, petroleum geology of carbonate and clastic reservoirs, and the integration of petrophysical data with geological data in detailed reservoir studies. He worked and published extensively in the fields of non-conventional gas from both tight sandstones and shales, petrophysics, source rock analysis and basin modeling. He conducted and supervised projects in most sedimentary basins of North America as well as South America, Europe, Southeast Asia, and Austrailia.
Bob received his BS degree in Geology from the University of California at Riverside (high honors) and an MS in Geology from the University of Wisconsin at Madison. He took additional graduate and undergraduate studies in geology, physics and mathematics at the University of Illinois at Urbana-Champaign, University of Colorado at Denver, and Metropolitan State College of Denver. From 1976 to 1981 he was a geologist with the Coal and Oil and Gas Sections of the Illinois State Geological Survey, worked as an independent consulting geologist from 1982-1986, founded The Discovery Group in 1987.
Bob was very active in several professional societies including the American Association of Petroleum Geologists, Society of Petroleum Engineers, the Rocky Mountain Association of Geologists (past-President 2006), the Denver Well Logging Society (past-President), and the Society of Petrophysicists and Well Log Analysts (Vice President Technolgy; Vice President Membership, Regional Director North America).
He was a registered geologist in the states of Texas (1873), Illinois (196-000177), and Wyoming (313), and was a DPA Certified Petroleum Geologist (3168).