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NOVEMBER 2019 TECHNICAL LUNCHEON & ANNUAL MEETING


November 13th, 2019 11:30 AM - 1:00 PM

                     

TECHNICAL LUNCHEON & ANNUAL MEETING

November 13, 2019 

Nominations from the floor for members to serve on the OCGS board as a director will be taken at the meeting.  Please consider serving.

SPEAKER: FRANK R. ETTENSOHN   

Filling Foreland Basins: Models from the Appalachian Basin and Elsewhere” 

PLEASE NOTE THAT THE MEETING WILL NOT BE HELD AT THE OCGS DEVON GEOSCIENCE CENTER 

IT WILL BE HELD IN THE MAPLE ROOM BUILDING 12

AT Chesapeake Campus

MAP ATTACHED.  

WEDNESDAY 13, 2019

LUNCH 11:30am – 1:00pm

MEMBER COST $25.00

VISITOR COST $35.00 

RESERVATIONS MUST BE SUBMITTED Friday November 8, 2019 BY 12:00 NOON 

 

The Appalachian Basin is a composite, retroarc foreland basin that in many ways is the “type” foreland basin and the “type area” for the Wilson cycle. Hence, understanding how the Appalachian Basin was filled may help in understanding the filling and sedimentary sequences in other foreland basins.

The Appalachian Basin exhibits 13 third- to fourth-order unconformity-bound cycles that have been interpreted to be flexural, foreland-basin manifestations of distinct episodes of tectonism, called tectophases, during five orogenies. These orogenies represent closure of the Iapetus and Rheic oceans during formation of the Pangean supercontinent.

The orogenies were typically polyphase events that included two or more tectophases, or deformational episodes, commonly focused at different places and times along an orogen. The sedimentary record in the composite Appalachian foreland basin, along with available radiometric, deformational, and magmatic data, suggests that during five Paleozoic orogenies along the Laurentian/Laurussian margin, tectophase timing and occurrence were mediated by diachronous convergence at successive promontories. Projecting promontories served to localize tectonism because of greater shortening and more intense deformation, while intervening reentrants served as sediment sinks. The greater intensity of deformation and resulting deformational loading at promontories, moreover, insured greater flexural subsidence in adjacent parts of the foreland basin so that major basin depocenters or sub-basins are located just behind or adjacent to respective promontories. Hence, diachronous, oblique convergence with successive promontories generated tectophases during each orogeny that are reflected by distinct, unconformity-bound, flexurally related sedimentary cycles in the foreland basin.

The cycles show a consistent sequence of lithologies, called tectophase cycles. Overlying a bulge-related unconformity, marine black shales initiate most cycles, are prominent and easily mapped, and mark the time of maximum deformational loading and flexural subsidence; by mapping the distribution of these shales in time and space, it is even possible to track the along-strike progress of orogeny relative to promontories. The shales in each cycle are overlain by a series of relaxational clastics, including deeper-water, flysch-like clastics followed by more shallow, marginal-marine, molasse-like clastics.

Similar tectophase cycles are known from the Black Warrior, Alpine and South China foreland basins, and may be present elsewhere. The cycles suggest that the black shales, as hydrocarbon source and reservoir rocks, and overlying clastics, as major reservoir rocks, are clearly the product of distinctive tectonic frameworks and histories, and aside from any economic value, may provide additional controls on the timing and location of tectonic events.

 

Short Biography for F.R. Ettensohn:

Frank Ettensohn grew up in Cincinnati, Ohio, and from an early age, was collecting fossils and rocks and telling people about them, which is what he still does as a professor at the University of Kentucky. He received his B.S. and M.S. in Geology from the University of Cincinnati and his Ph.D. in Geology from the University of Illinois at Urbana-Champaign in 1975; in 1970-1971, he was a Combat Engineer Platoon leader in the U.S. Army Corps of Engineers. Frank has been teaching and researching in sedimentary geology and paleontology since arriving at the University of Kentucky in 1975; he was chair of his Department for eight years and was director of the University Honors Program for four years. He has taught in high school, the military, teacher-development, the U.S. State Department, and as a visiting professor in the former Soviet Union, China, Ecuador, and Nepal. He was awarded two Fulbright fellowships, two Levorsen Best Paper Awards, an eastern AAPG Educator of the Year Award, a Kentucky AIPG Lifetime Achievement Award, the Superlative Award for a Distinguished University Scientist by the Kentucky Academy of Sciences, a AAPG Grover E. Murray Memorial Distinguished Educator Award, and the AIPG Ben H. Parker Distinguished Service Medal. He is an Arts & Sciences Distinguished Professor at the University of Kentucky, GSA and AAAS Fellows, worked for a year in the U.S. State Department as a Jefferson Science Fellow, and worked in the Ukraine as an Embassy Science Fellow on the international implications of shale gas. He is a Registered Professional Geologist in Kentucky and a Certified Professional Geologist through AIPG. He is widely published and has advised 50 graduate students to degree completion. He has found that encouraging student research, public presentations and publication is a way to build interest in geology while building student confidence in their ability to be successful geologists. Hence, students are coauthors on nearly half of his papers. His geology teaching is largely field- and problem-based, and he has developed a number innovative, field-oriented courses for non-geology majors that integrate non-geology subjects. He is also especially interested in undergraduate education and teacher development in the sciences and math. He is known nationally and internationally for his work on the geology of the Appalachian Basin and for his work on U.S. oil and gas shales. His models for foreland-basin sedimentation, involving the integration of stratigraphy, regional tectonics, and flexural movements in the crust, are widely used. He indicates that interactions with students and colleagues have been the source of much creativity in his teaching and research. “Many of my best ideas were generated by the need to explain complex ideas more simply for students and colleagues.”

 

Attendance without reservation will not be possible.  Reservations must be cancelled by November 8, 2019 at noon to avoid being charged.  Thank you for your consideration.