Mars’ catastrophic geology
by Wayne Spencer
Image NASA/JPL/Malin Space Science Systems
New information about Mars is highlighting the catastrophic nature of its past.
Planetary geologists are finding a variety of indications of very rapid processes
in Mars history. These processes often have some parallel on Earth but because Mars
is much colder and has a very different atmosphere there are differences in the
effects even for well known Earth-like processes.
Martian processes include flooding, volcanism, glacial movement, sedimentary processes
and even geysers. NASA and the European Space Agency have gathered valuable data
on Mars geology from recent missions that will give new insights into Mars history.
How should young-age creationists understand this new information?
The Northern part of Mars is called the Northern Lowlands because it averages about
4–5 km lower in elevation than the Southern half of the planet. The Southern
Highlands are very densely cratered but fewer craters are seen on the surface in
the Northern Lowlands. On the other hand, the Northern Lowlands has many buried
craters. In 2006, the European Space Agency’s Mars Express mission (also known
as MARSIS) found evidence of what are apparently impact structures buried under
the surface ranging from 130 to 470 km in diameter.1 This was using a special instrument known as a sounding
radar. Mars is well known for many channels on its surface as well. Most of the
channels formed as a result of subsidence phenomena, but there are often dendritic
drainage patterns in or around them, indicating water drained into them or eroded
in them after their formation.
Mars’ atmosphere is quite thin and if there were liquid water on the surface
of Mars today it would quickly evaporate and/or freeze. Water and carbon dioxide
ice exist on both the poles of Mars and water ice under the surface. Recently the
Mars Odyssey spacecraft mapped patches of water ice just below the surface.2 Being a planet with a relatively
low density (3.9 g/cm3 compared to 5.5 for Earth), Mars has the potential
for having a lot of volatile material in its interior, such as water and carbon
dioxide.
Eruptions propelled material several kilometres laterally across the surface
Evidence seems to have been discovered recently of water eruptions3 sometime in Mars’ past from two channels on
Mars known as Mangala Fossa and Cerberus Fossa, described as graben fractures. Mangala
Fossa seems to have had hot water carrying mud with it. Scientists have estimated
107 –108 m3/s for the water volume flux from
Mangala Fossa from a fracture about 200 km long. Cerberus Fossa (fracture about
35 km long) seems to have been a carbonated water geyser with a volume flux of about
2 × 106 m3/s. Both of these eruptions propelled material
several kilometres laterally across the surface. The nature of the channels and
ridges produced by these eruptions seem to rule out volcanic flows. Cerberus Fossa
is believed to have sent hailstones several kilometres. The force of these eruptions
requires that the water come from aquifers as deep as 3–4 km below the surface.
These water eruptions are just one example of a variety of large-scale rapid catastrophic
events that have shaped the surface of Mars in its past. There are also massive
volcanoes and evidence of glaciation. A major ongoing mystery is how the Martian
atmosphere could support so much liquid water in the past, as is indicated by all
the evidence of water on the surface. There are sedimentary deposits of sulfate
and clorite compounds (evaporites), as well as hematite. A mineral similar to granite
was also found in limited quantities.4
This suggests a variety of processes that may involve water coming up from below
the surface.
Whatever happened in Mars’ past, it was dramatic and catastrophic.
There is much yet to be thoroughly researched and examined on Mars from a young-age
creation perspective. For example, was Mars created with a thicker atmosphere than
present that was partially lost as a result of large impacts? It is very possible
for the explosion of a large impact to blast gases away at greater than escape velocity,
especially since Mars gravity is about 38% of Earth’s. An alternative might
be powerful outgassing from the interior after creation (possibly driven by accelerated
radioactive decay) that increased the density of the atmosphere at least temporarily.
Then heating from the interior could have triggered a massive melting of glaciers
and subsurface ice, causing much erosion of the surface from liquid water that flowed
for some period of time. There’s obviously been massive lava flows on Mars
as well. But, something has caused a melting or evaporation of water under the surface
that led to water flows creating many surface channels. There may have also been
large regions once glaciated on Mars that have been resurfaced by basalt and dust.
Whatever happened in Mars’ past, it was dramatic and catastrophic. Though
this is all tentative at this point, Martian geology will generally demand rapid
catastrophic processes and thus will fit a young-age viewpoint nicely.
A reader’s commentRoger d., New Zealand, 28 August 2009
“Cerberus Fossa is believed to have sent hailstones several kilometres.”
I don’t understand how the eruption could have sent hailstones, based on the description of the Mangala Fossa having consisted of hot water carrying mud, I would have thought the Cerberus Fossa would have also been hot, or is it an ice geyser? Wayne Spencer responds:
Cerberus Fossa was said to be carbonated water, not muddy water. Mangala Fossa was said to have been muddy water. However, it is compared to the Old Faithful Geyser at Yellowstone, only much more powerful. Hot water erupting like Old Faithful could carry some mud with it but the mud is not vaporized like the water so it separates out and doesn’t travel so far. The mud might come down as dust, I would guess. It would indeed be very hot when it erupts but remember the temperature on Mars varies at the surface from around-120 C to maybe 35 C in summer and it gets colder with altitude. There are also significant seasonal temperature changes on Mars. If water is being propelled a long distance it may have time for the water to freeze and come down as snow or hail. It’s a kind of unusual type of erosion that they found on the surface so more research may lead to more ideas.
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Further reading
Recommended Resources
References
- Watters, T.R., Leuschen, C.J., Plaut, J.J., Picardi, G., Safaeinili,
A., Clifford, S.M., Farrell, W.M., Ivanov, A.B., Phillips, R.J. and Stofan, E.R.,
MARSIS radar sounder evidence of buried basins in the northern lowlands of Mars,
Nature 444:905–908, December 14, 2006. Also available
as a press release at <mars.jpl.nasa.gov/express/newsroom/pressreleases/20061213a.html>.
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- Sharp views show ground ice on Mars is patchy and variable,
3 May 2007, <themis.asu.edu/news-groundice>. Return to text.
- Shiga, D., Fizzy water powered ‘super’ geysers
on ancient Mars, New Scientist News, 17 March 2008, <space.newscientist.com/channel/solar-system/dn13480-fizzy-water-powered-super-geysers-on-ancient-mars.html>.
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- Bandfield, J.L., Hamilton, V.E., Christensen, P.R. and McSween
Jr, H.Y., Identification of quartzofeldspathic materials on Mars, J. Geophys. Res.
109:E10009, 2004. Or, see, Granite-like rocks discovered, <themis.asu.edu/discoveries-granitepeaks>.
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| Ken E. wrote: “I just wanted to drop a note to express my gratitude for the kind of information you supply at the CMI web-site. I love science and find it thrilling to see how it may be used to glorify God and build faith in Him.” Glorify God in His creation.  | | |
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