The miles wide asteroid that struck the earth at the K/Pg boundary event, leaving an imprint at Chicxulub, is now said to have triggered a ‘monster‘ tsunami wave that scoured the ocean floor thousands of miles away from the Yucatan. The new study comes from the University of Michigan and is published in AGU Advances, the journal of the American Geological Union [October 4th 2022]. The researchers, using a simulation fo the impact, also made use of geological evidence from more than one hundred sites around the world. They found evidence of the model’s predicted tsunami pathways, including data from as far away as New Zealand.
The tsunami wave was strong enough to erode sediments in ocean basins halfway around the globe, leaving a gap in the sedimentary records or a jumble of disturbed older sediments. It was therefore capable of dumping some of those sediments on land we may assume. The implication of this is enormous. For example, the distribution of the erosion and hiatuses in the uppermost Cretaceous marine sediments deposited just before or just after the impact, close the Cretaceous and open the Paleogene. Simulation shows the tsunami or tidal wave radiated mainly towards the east and north east, into the North Atlantic [as it then was]. The configuration of the coastal region probably differed during the dinosaur age, as far as North America and Europe are concerned. The energy involved was an incredible 30,000times stronger than the Christmas tsunami in the Indian Ocean. That means a lot of water, and a lot of sediments were moved. How does this affect chalk geology?
The simulation also shows the tsunami radiated through the Central American Seaway into the Pacific. Did the seaway really exist, we might ask, or is this physical evidence of the passage of the tsunami wave, transformed into a long term feature by the uniformitarian theory of slow and gradual change? Other regions, such as the Mediterranean basin, do not seem to have been affected by the tidal wave.
Two and a half minutes after the impact a curtain of ejected material pushed a wall of water away from Chicxulub, forming a 4.5km high wave that subsided as the ejecta fell back to earth. Ten minutes later a 1.5km high tidal wave swept across the ocean in all directions. Four hours later the wave had poured through the Central American Seaway and had reached the other side of the Pacific.
A follow up study is planned to model the effects on coastal regions of the world. They first have to establish where those coastlines were in the Cretaceous.
See https://phys.org/news/2022-10-dinosaur-killing-asteroid-triggered-global-tsunami.html …