GSA Thompson Field Forum 2019

“Age and Carving of Grand Canyon: Towards a Resolution of 150 Years of Debate”

An eight-day, 280-mile field conference by raft through the Grand Canyon

Exploring Grand Canyon by Raft
Exploring Grand Canyon by raft.

On September 14-22, 2019 we journey down the ‘Great Unknown’. The age and evolution of the 1-mile-deep, 270-mile-long Grand Canyon have been debated since J.W. Powell’s exploration of the Colorado River in 1869. This GSA Thompson Field Forum honors the 150th anniversary of Powell’s trip. It will involve 28 researchers and young scientists who will discuss the evidence for the age and incision history of Grand Canyon in the context of recent advances and ongoing debates. The objective is to promote a next generation of research on the evolution and tectonic geomorphology of this iconic region, as well as similar studies globally, and debate the evidence for and against mantle-driven dynamic topography. Karl Karlstrom (UNM), Laura Crossey (UNM), and Ryan Crow (USGS) will coordinate field stops and discussions of incision data, neotectonics, and hydrology studies. Eugene Humphreys (U of O) will coordinate geodynamics discussions to debate the hypothesis for mantle-driven uplift of the Colorado Plateau–Rocky Mountain region. David Shuster (UC-Berkely) will coordinate discussions of thermochronologic studies of now-eroded landscapes. Kelin Whipple (ASU) will coordinate geomorphology discussions of bedrock strength controls on river and canyon morphology and debate evidence for steady versus transient incision. Following the trip there will be reports and social media materials available. Stay Tuned!!


Marble Canyon
Marble Canyon above Nankoweap.

Additional Opportunities

For those going to the GSA Annual Meeting, check out talks and presentations by the same group at the Pardee Symposium!

MONDAY, Sept. 23. T1. Grand Canyon, Colorado Plateau, and Rocky Mountain Debates and Their Global Reverberations, 150 Years after Powell

The age and origins of the Grand Canyon have long been debated. This session adds to the discussion with talks about river incision, drainage reversal, ichnology of the Coconino sandstone, and the Canyon’s Great Unconformity. Oral sessions on Monday and Tuesday, posters on Wednesday.

About Thompson Field Forum format:

Geologists afoot in Grand Canyon.

GSA’s Thompson Field Forums provide the perfect format for the exchange of current knowledge and exciting ideas best expressed by the geology of a specific area. They are designed after the Penrose Conferences but are held almost completely in a field setting. The intent is to stimulate and enhance individual and collaborative research and to accelerate the advance of the science by interactions in the field. GSA helps to provide logistical support.