244 Geophysics/Tectonophysics/Seismology (Posters)
Wednesday, 12 October 2011
9:00 AM - 6:00 PM
Hall C
PLAUSIBLE EXPLANATIONS FOR TWO MAJOR EVENTS IN EARTH HISTORY
Paper number: 244-1
Program: Technical Sessions
Time: 9:00 AM – 6:00 PM
Authors
Abstract
Subsequently, rivers draining substantial basins from what is now California contributed to the formation of Monterey Canyon. The canyon was likely formed above the ocean’s surface – its associated river system, extending nearly 70 miles into the Pacific basin, created oxbows, one of which is nearly 50 miles off the coast (visible in Google Maps) where seabed gradients are much lesser than at the coast. The system is well preserved. At its extent, the complex is submerged 3.6 km beneath the present ocean surface. Such a volume of water could not have terrestrial origin. Evidence of a subsequent, less energetic impact of sufficient size to add the volume is identified in the Southern Ocean and offered as a plausible explanation.