PROBLEM IV
TERRESTRIAL GEOLOGY AND
LUNAR CRATERS

REASONABLY enough, Velikovsky believes that a near-collision of another planet with the Earth might have had dramatic consequences here—by gravitational tidal, electrical or magnetic influences (Velikovsky is not very clear on this). He believes (pages 96 and 97) “that in the days of the Exodus, when the world was shaken and rocked … all volcanoes vomited lava and all continents quaked.” (My emphasis.)

There seems little doubt that earthquakes would have accompanied such a near-collision. Apollo lunar seismometers have found that moonquakes are most common during lunar perigee, when the Earth is closest to the Moon, and there are at least some hints of earthquakes at the same time. But the claim that there were extensive lava flows and volcanism involving “all volcanoes” is quite another story. Volcanic lavas are easily dated, and what Velikovsky should produce is a histogram of the number of lava flows on Earth as a function of time. Such a histogram will, I believe, show that not all volcanoes were active between 1500 and 600 B.C., and that there is nothing particularly remarkable about the volcanism of that epoch.

Velikovsky believes (page 115) that reversals of the geomagnetic field are produced by cometary close approaches. Yet the record from rock magnetization is clear—such reversals occur about every million years, and not in the last few thousand, and they recur more or less like clockwork. Is there a clock in Jupiter that aims comets at the Earth every million years? The conventional view is that the Earth experiences a polarity reversal of the self-sustaining dynamo that produces the Earth’s magnetic field; it seems a much more likely explanation.

Velikovsky’s contention that mountain building occurred a few thousand years ago is belied by all the geological evidence, which puts those times at tens of millions of years ago and earlier. The idea that mammoths were deep-frozen by a rapid movement of the Earth’s geographical pole a few thousands of years ago can be tested—for example, by carbon-14 or aminoacid racemization dating. I should be very surprised if a very recent age results from such tests.

Velikovsky believes that the Moon, not immune to the catastrophes which befell the Earth, had similar tectonic events occur on its surface a few thousand years ago, and that many of its craters were formed then (see Part 2, Chapter 9). There are some problems with this idea as well: samples returned from the Moon in the Apollo missions show no rocks melted more recently than a few hundred million years ago.

Furthermore, if lunar craters were to have formed abundantly 2,700 or 3,500 years ago, there must have been a similar production at the same time of terrestrial craters larger than a kilometer across. Erosion on the Earth’s surface is inadequate to remove any crater of this size in 2,700 years. There are not large numbers of terrestrial craters of this size and age; indeed, there is not a single one. On these questions Velikovsky seems to have ignored the critical evidence. When the evidence is examined, it strongly counterindicates his hypothesis.

Velikovsky believes that the close passage of Venus or Mars to the Earth would have produced tides at least miles high (pages 70 and 71); in fact, if these planets were ever tens of thousands of kilometers away, as he seems to think, the tides, both of water and of the solid body of our planet, would be hundreds of miles high. This is easily calculated from the height of the present water and body lunar tide, since the tide height is proportional to the mass of the tide-producing object and inversely proportional to the cube of the distance. To the best of my knowledge, there is no geological evidence for a global inundation of all parts of the world at any time between the sixth and fifteenth centuries B.C. If such floods had occurred, even if they were brief, they should have left some clear trace in the geological record. And what of the archaeological and paleontological evidence? Where are the extensive faunal extinctions of the correct date as a result of such floods? And where is the evidence of extensive melting in these centuries, near where the tidal distortion is greatest?