Escape from Egypt
Are you familiar with the story of Exodus? About 4000 years ago, Moses led the Hebrew people out of Egypt. They were however, closely pursued by Pharaoh’s chariots. The story states that some relative motion of water and land delayed or destroyed the Egyptian forces and allowed the Hebrews to escape.
We’ve all seen the Hollywood telling of this event in the “Ten Commandments”, where Charlton Heston splits the Red Sea for a while, then zips it back up over the tailing troops.
To the extent that physical laws govern the motions of land and water, it seems to me that a geophysical perspective on Exodus might shed unique light on the story. For instance, did the land stay fixed and the water rise and fall, or did the water stay at the same level and the land rise and fall? Why does it matter? It matters because very different physical processes would be at play.
What about sequencing? Was it “WET-DRY-WET”, or “DRY-WET-DRY” or simply “DRY-WET”. The first involves displacing water from its equilibrium position for a period of time and then a return. This is difficult, as you would be fighting the force of gravity. The second sequence suggests transient phenomena --- a passing wave or flash flood. This may be easier to accommodate. “DRY-WET” requires just a single stage, perhaps a one-time flooding of a lowland or submergence/erosion of ‘soft’ ground. Escape from pursuit does not necessarily mean destruction of the pursuers. Frustration of their advance serves equally well. For this, one meter of water suffices.
In this movie, I’ve put together a variety of natural causes that could induce relative motions of water and land in the Nile Delta. The mechanisms span the usual suspects: tsunami from earthquakes, volcanoes and submarine landslides; but they also include the arcane like flash flood, hurricane wind, even intentional sabotage.
I don’t know where, how, or if water movements aided the Exodus Escape, but from a geophysical perspective, plausible mechanisms exist. Granted, none are as cool as the Hollywood version.
Steven N. Ward Santa Cruz
About OpenHazards Bloggers
Steven Ward is a Research Geophysicist at
the Institute of Geophysics and Planetary Physics, UC Santa Cruz. He specializes in the quantification and simulation of
natural hazards. Read Steve's blog.
John Rundle is a Distinguished Professor of Physics
and Geology at UC Davis and
the Executive Director of the APEC Collaboration for Earthquake Simulations. He
chaired the Board of Advisors for the Southern California Earthquake Center from 1994 to 1996. Read John's blog.
Comments
Some powers are actually greater than those possessed by us. That's what rushmyessays had helped me learn earlier. We shouldn't question it's happening, it happened, that's something we still quite don't understand yet.