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Jun 06, 2005
The “Caldera” of Olympus Mons

Among the many paradoxes of Olympus Mons are the complex networks of shallow grooves on the flat floors of the summit craters. The common interpretation of these linear depressions as faults can no longer be maintained.

Called the “largest volcano in the solar system”, the great mound of Olympus Mons on the planet Mars is taller than three Mount Everests and about as wide as the entire Hawaiian Island chain.

In previous Pictures of the Day, we have noted that the defining characteristics of Olympus Mons find no counterparts in known volcanoes on Earth. Rather, the towering mound reveals the telltale markers of a lightning blister, as do its companion mounds on the equatorial Tharsis Bulge.

The “pancake” shape of the mount, with its steep scarp almost four miles high, finds its best analog in the bell-shaped blisters found on the caps of lightning arrestors. The “moat” around much of the base of Olympus Mons also has its counterpart in the lightning blister. Familiar volcanic domes do not reveal such features.

Nothing like the overlapping flat-bottomed craters of the “caldera”, nearly two miles deep, are observed in volcanoes on Earth. But the pattern matches the features of craters formed atop laboratory discharge blisters on an anode, or positively charged surface. The discharge creates the flat bottoms of these craters by electrical machining of the summit, vaporizing surface material to create smooth and flat crater floors.

In the electrical hypothesis the same force that raised the blister cut the superimposed craters on the summit. But an event of such power would surely leave trademark scars explicable by no other hypothesis! We have noted, for example, the pits, scoops and gougesnear the summit of Olympus Mons. Here, the geologists’ explanations (“collapse pits”, etc.) do not withstand scrutiny, while the formation of such pits by electric arcs is well known to everyone familiar with the effects of electric discharge machining (EDM). For a similar example of scooped out pits in association with the great chasm of Valles Marineris, see the chain of craters on the far left of the picture here.

In our Picture of the Day for March 7, 2005, we observed that the finely filamented “mane” radiating down the flanks of the mount presents the telltale evidence of charge redistribution. The extremely shallow grooves of the “mane” offer clear evidence that the summit of Olympus Mons, the focal point of a massive electrical discharge, acquired a strongly negative charge as the arriving electrons of the discharge raised the mound and excavated the craters. We wrote: “To achieve surface equilibrium, then, secondary discharging occurred between the "caldera" of Olympus Mons and the surrounding region in a way analogous to the discharge of a negatively charged comet nucleus as it enters the positive region of the Sun's electric field”.

The hypothesis set forth here can now be tested against the superb images returned by orbiting cameras. In the picture above, the best ever taken of the complex caldera, we see regions of the caldera cut by shallow grooves or channels. Planetary scientists had previously identified these with grabens or faults on the flat surfaces of crater floors. This interpretation simply followed the standard ideology of Olympus Mons, which sees the flat floors as former lakes of molten lava. But look closely at these sharply cut grooves. We have placed higher-resolution images of the inset regions here and here. Do you see any evidence of faulting? It is not necessary to guess here, since the grooves extend from the walls of deeper, flat-floored craters. These steep cliffs are where the most obvious evidence of faulting would appear. The evidence is not there.

Not a hint of surface spreading is evident: what we see instead are scratches across the surface, as if giant claws reached down to scoop out braided channels.

But perhaps these grooves already look familiar to you. We’ve seen them before, cutting across the buttes of Labyrinthus Noctis on the western termination of Valles Marineris. And for an even more dramatic parallel, consider the network of undulating and entwining grooves on Saturn’s moon Enceladus.

The irony is that the advanced engineering that allowed our probes to reach distant planets and capture such compelling images appears to be far ahead of the established theories. But now things are certain to change, just as soon as the specialists are able to look at the pictures directly, not through the lens of prior assumptions.


David Talbott, Wallace Thornhill
Amy Acheson
  CONTRIBUTING EDITORS: Mel Acheson, Michael Armstrong, Dwardu Cardona,
Ev Cochrane, C.J. Ransom, Don Scott, Rens van der Sluijs, Ian Tresman
  WEBMASTER: Michael Armstrong

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