2009 Portland GSA Annual Meeting (18-21 October 2009)
403 Wednesday, 14 October 2009
2:00 PM-6:00 PM, Oregon Convention Center:

Central and Eastern Portions of the Columbia River Flood-Basalt Province – An Overview of Our Current State of Knowledge of Flood-Basalt Stratigraphy, Vent Geometries, Flow Emplacement Mechanisms, and Tectonics

Primary Leader: Terry L. Tolan
Leader(s): John D. Kaufmann, Barton S. Martin, Stephen P. Reidel
Field Trip Description: The Columbia River Flood Basalt Province is one of the best exposed and understood Large Igneous Provinces (LIP) in the world. Decades of detailed geologic mapping, stratigraphic studies, petrologic studies on the origin of the basalts, and tectonic studies have provided insight into the evolution of the province. This three day trip will visit a mix of “classic” and new localities in the central and eastern province that are fundamental to unraveling the geologic and tectonic evolution of this LIP. Participants will be introduced to recent refinements in Columbia River basalt stratigraphy, the nature of dikes and vents, eruptive/flow emplacement histories, as well as new insights into the structural geology of this region and its tectonic evolution. Evidence for and against the Plume Model will be examined and discussed. The first day of the field trip will be in the south-central Columbia Basin and will focus on Columbia River basalt vents/feeder dikes, flow emplacement, intraflow structures, and the structure geology of the Columbia Basin and western Palouse Slope. The second day of the trip will examine features on the eastern margin of the Province where most of the basalt erupted in a complex tectonic environment, and where evidence for and against the Plume Model can be seen. The final day will examine the western Columbia Plateau and Columbia River Gorge, and will focus on the structural geology of the Yakima Fold Belt, Columbia River basalt intracanyon flows, and the ancestral Columbia River paleodrainage history.
Field Trip will span: 3 days
Sponsor(s):

Back to the 2009 Portland GSA Annual Meeting (18-21 October 2009)
General Information for this Meeting