GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 22-8
Presentation Time: 10:15 AM

EXPLORING ICE AGE MEGAFLOODS VIA DRONE


BJORNSTAD, Bruce N., Ice Age Floodscapes, 1918 Harris Ave, Richland, WA 99354, bjorn99352@yahoo.com

Drones (i.e., unmanned aerial vehicles) today often generate negative attitudes. One of the many positive uses of drones, however, is the collection of unique imagery of our natural environment, including dramatic evidence of Pleistocene megafloods. These repeated outbursts produced a unique assemblage of over-sized landforms in the Pacific Northwest, especially within the Channeled Scabland of eastern Washington. Huge floods produced huge landforms. Examples include giant current ripples up to 15 m tall and 200 m apart, deep waterless cataract canyons, and scarred basalt surfaces. Because the scale of megaflood landforms is so large most are not apparent or visible at ground level. Thus, megaflood landforms are best examined and appreciated from an aerial perspective, particularly via new, rapidly evolving drone technology that allows users to view and record imagery in real time.

Unlike standard aircraft, camera-equipped drones provide a relatively inexpensive and easy way to remotely evaluate landforms from 0-500 m height by hovering in a single location, easily shifting in any direction, including backwards, or circling around a point of interest. Versatile drones are especially useful for observing the interior of giant, cavernous potholes tens of meters deep and wide, which can’t be safely observed any other way. Other potentially dangerous places include tall, steep exposures of weakly consolidated rhythmites, which reveal the history of repeated megaflooding in slackwater areas. Elsewhere, drones can fly over huge flood bars, some an incredible 150 m tall and 3 km long. New discoveries by drone are also possible, especially from slower-moving and low-elevation perspectives. An example is flood-exhumed, basaltic ringed craters that appear to be more common than previously realized. Drones can precisely capture all the important elements of landforms in a single appealing image or video, easily shared online with the world.

To share the captivating story behind Ice Age megafloods the author created an online YouTube Channel named Ice Age Floodscapes, where viewers may more easily comprehend and appreciate these huge cataclysms from the Ice Age. To illustrate, segments from several Floodscape videos will be shared with the audience.