Thanks to a research partnership with Hyperdynamics Corporation, the UA Geosciences geophysics group has the unprecedented opportunity to work with a very large amount of sophisticated, 2-D and 3-D seismic reflection data from a relatively unexplored area offshore Guinea, West Africa.
Hyperdynamics, an independent exploration and production company led by Geosciences alumnus Ray Leonard (BS '75), has provided research support for our reflection seismology group to work to better understand the tectonic evolution, volcanism and subsurface structure of the area.
“This is a great example of academic-industry partnering and the opportunities it provides for student engagement,” said Geosciences Department Head Peter W. Reiners. “We have access to industry resources and experts, and we are doing real science and training students in cutting edge technology of 3-D visualization and new geophysical methods at the same time.”
The Guinea continental margin lies at the point of final separation between the North American, African and South American tectonic plates. North America split away in the Early Jurassic Period (~ 180 Ma) forming the North Atlantic Ocean basin. Africa and South America began rifting apart from south to north to form the evolving South Atlantic Ocean, but a through-going Mid-Atlantic seaway was not established until the Early Cretaceous (~ 110 Ma) as rifting and separation between Africa and South America became complete along the Guinea margin. The Atlantic Ocean continues to widen as rifting persists between the continents along the Mid-Atlantic Ridge.
The rifting process, along with formation of oceanic fracture zones, created a very complex tectonic and structural environment in the Guinea margin with faulting and rapid sediment deposition punctuated by volcanic eruptions and intrusions. The subsurface data show old, rift-related and post-rift volcanoes buried by thick sedimentary rock sequences, large extensional faults, and numerous depositional fan sequences, fault blocks and other structures of interest to explorationists. “Part of our focus is to identify and map now-buried volcanic and intrusive features to help determine their geometries and their timing of emplacement,” said Professor Roy Johnson, who is leading the Geosciences side of the project.
“This is complicated work, but it has been greatly facilitated using new seismic workstations and large data-storage capacity made possible by research funding from Hyperdynamics, which has also supported our IT staff and, primarily, the thesis and dissertation work of seven geophysics graduate students,” Johnson said.
Ray Leonard, Hyperdynamics President and CEO also commented on the collaboration’s benefits. “The partnership between the Department of Geosciences and Hyperdynamics for the past four years has been mutually beneficial,” Leonard said. “The Department has had access to a large state-of-the-art 3D seismic survey for research and teaching purposes along with financial support, while Hyperdynamics has had the benefit of excellent research studies on tectonics and identification of volcanic and carbonate features on the block.”
“The exceptional quality of the state-of-the-art 3-D data from offshore Guinea makes interpreting geologic features quite exiting and always fascinating,” said Johnson.
The data cover an area of roughly 87,000 square kilometers on the Guinea margin, and include over 9,300 square kilometers of high-quality 3-D seismic data, which is sampled every 25 m in map view and every 5 m in depth to 10,000 m.