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Course Description:
Understanding the key controls on the distribution and geometry of carbonate plays is critical to enhanced exploration/exploitation in any basin. Further, delineating potential carbonate plays from seismic or wireline logs requires a very sound understanding of the depositional and diagenetic controls that create the reservoir facies, which must be considered within the context of geological age and physiographic setting. One should appreciate the environmental controls on carbonate facies development, and the potential pathways for diagenesis and porosity evolution.
This short course reviews the key controls on carbonate facies occurrence and distribution, and demonstrates the strong influence of physiographic setting, both at the global and local scale. Because most Paleozoic carbonate reservoirs were developed within tropical or subtropical settings, paleotrade winds often influenced their occurrence and distribution. In addition, favorable limestone diagenesis or dolomitization controlled porosity and permeability evolution in these plays. Discerning the relative timing of secondary porosity development in these carbonates is key to exploiting regional porosity trends.
This short course first discusses key aspects of carbonate diagenesis and porosity evolution for limestones and dolostones. It reviews existing depositional paradigms for carbonate platforms and ramps and introduces the newer paleotrade wind models and applications. This seminar culminates with a discussion of conventional and unconventional carbonate play types (occurrence, geometry and distribution) related both to geological age and local physiographic setting (platform versus ramp bottom topography). This discussion will be applied to specific Paleozoic play type examples from the Midcontinent area. In doing so, the role that deep-seated faulting often plays in carbonate diagenesis and development of reservoir quality, as well as hydrocarbon entrapment, will become apparent.
The key take-aways from this seminar apply to other Paleozoic sequences elsewhere in the U.S., Canada and other basins worldwide. If you are working Mesozoic and younger carbonate successions, the guidelines from this seminar apply to them, as well.
Instructor Bio:
Jeff Dravis is a carbonate geologist whose consulting activities primarily focus on aiding the discovery of oil and gas deposits, or enhancing their development once they are discovered. He also conducts numerous applied carbonate training seminars for industry every year.
Jeff received his Bachelor of Science degree in Geology from St. Mary’s University in San Antonio, Texas. He then obtained a Master of Science degree in Marine Geology from the University of Miami’s Rosenstiel School of Marine and Atmospheric Sciences in Miami, Florida. His thesis was entitled “Holocene Sedimentary Environments on Eleuthera Bank, Bahamas” and was supervised by Dr. Harold R. Wanless. In 1976, Jeff entered Rice University, Houston, Texas, to work on deep-water carbonates under the direction of Dr. James Lee Wilson. He was awarded a Ph D in Geology; his dissertation was entitled “Sedimentology and Diagenesis of the Upper Cretaceous Austin Chalk Formation, South Texas and Northern Mexico.”
Dr. Dravis began his professional career in Houston in 1979 with Exxon Production Research Company. There, he conducted applied research on carbonate facies, diagenesis and porosity evolution, but also headed up Exxon’s worldwide training efforts in carbonates. This training included teaching in-house seminars, as well as leading 25-day combined modern (Bahamas and S. Florida) and ancient (Texas and New Mexico) carbonate field seminars for the corporation.
In 1986, Jeff started a geological consulting practice in Houston. He founded Dravis Interests, Inc. to provide technical expertise and training in applied carbonate geology to the oil and gas industry. Later, Dravis Geological Services was created to
handle all technical consulting projects. To date, Jeff has completed nearly 200 technical projects worldwide, working on carbonate sequences ranging in age from Cambrian to upper Tertiary. He has presented 327 in-house and field seminars to industry, both on a public and private basis. This includes teaching 73 industry and academic seminars on Caicos Platform in the southeastern Bahamas, as well as numerous ancient carbonate field seminars in west Texas and New Mexico.
Jeff has been an Adjunct Professor of Geology at Rice University since 1987, where he has taught parts of graduate courses, taken students into the field, and served on thesis committees. In 2016, he began teaching the carbonate geology segment of the University of Houston’s Professional Master’s Program in Petroleum Geology and presented his sixth segment in January and February of 2023.
Understanding the key controls on the distribution and geometry of carbonate plays is critical to enhanced exploration/exploitation in any basin. Further, delineating potential carbonate plays from seismic or wireline logs requires a very sound understanding of the depositional and diagenetic controls that create the reservoir facies, which must be considered within the context of geological age and physiographic setting. One should appreciate the environmental controls on carbonate facies development, and the potential pathways for diagenesis and porosity evolution.
This short course reviews the key controls on carbonate facies occurrence and distribution, and demonstrates the strong influence of physiographic setting, both at the global and local scale. Because most Paleozoic carbonate reservoirs were developed within tropical or subtropical settings, paleotrade winds often influenced their occurrence and distribution. In addition, favorable limestone diagenesis or dolomitization controlled porosity and permeability evolution in these plays. Discerning the relative timing of secondary porosity development in these carbonates is key to exploiting regional porosity trends.
This short course first discusses key aspects of carbonate diagenesis and porosity evolution for limestones and dolostones. It reviews existing depositional paradigms for carbonate platforms and ramps and introduces the newer paleotrade wind models and applications. This seminar culminates with a discussion of conventional and unconventional carbonate play types (occurrence, geometry and distribution) related both to geological age and local physiographic setting (platform versus ramp bottom topography). This discussion will be applied to specific Paleozoic play type examples from the Midcontinent area. In doing so, the role that deep-seated faulting often plays in carbonate diagenesis and development of reservoir quality, as well as hydrocarbon entrapment, will become apparent.
The key take-aways from this seminar apply to other Paleozoic sequences elsewhere in the U.S., Canada and other basins worldwide. If you are working Mesozoic and younger carbonate successions, the guidelines from this seminar apply to them, as well.
Instructor Bio:
Jeff Dravis is a carbonate geologist whose consulting activities primarily focus on aiding the discovery of oil and gas deposits, or enhancing their development once they are discovered. He also conducts numerous applied carbonate training seminars for industry every year.
Jeff received his Bachelor of Science degree in Geology from St. Mary’s University in San Antonio, Texas. He then obtained a Master of Science degree in Marine Geology from the University of Miami’s Rosenstiel School of Marine and Atmospheric Sciences in Miami, Florida. His thesis was entitled “Holocene Sedimentary Environments on Eleuthera Bank, Bahamas” and was supervised by Dr. Harold R. Wanless. In 1976, Jeff entered Rice University, Houston, Texas, to work on deep-water carbonates under the direction of Dr. James Lee Wilson. He was awarded a Ph D in Geology; his dissertation was entitled “Sedimentology and Diagenesis of the Upper Cretaceous Austin Chalk Formation, South Texas and Northern Mexico.”
Dr. Dravis began his professional career in Houston in 1979 with Exxon Production Research Company. There, he conducted applied research on carbonate facies, diagenesis and porosity evolution, but also headed up Exxon’s worldwide training efforts in carbonates. This training included teaching in-house seminars, as well as leading 25-day combined modern (Bahamas and S. Florida) and ancient (Texas and New Mexico) carbonate field seminars for the corporation.
In 1986, Jeff started a geological consulting practice in Houston. He founded Dravis Interests, Inc. to provide technical expertise and training in applied carbonate geology to the oil and gas industry. Later, Dravis Geological Services was created to
handle all technical consulting projects. To date, Jeff has completed nearly 200 technical projects worldwide, working on carbonate sequences ranging in age from Cambrian to upper Tertiary. He has presented 327 in-house and field seminars to industry, both on a public and private basis. This includes teaching 73 industry and academic seminars on Caicos Platform in the southeastern Bahamas, as well as numerous ancient carbonate field seminars in west Texas and New Mexico.
Jeff has been an Adjunct Professor of Geology at Rice University since 1987, where he has taught parts of graduate courses, taken students into the field, and served on thesis committees. In 2016, he began teaching the carbonate geology segment of the University of Houston’s Professional Master’s Program in Petroleum Geology and presented his sixth segment in January and February of 2023.