Hypothetical Hazard Scenario at Olympus Mons, Mars
Volcanic activity at Olympus Mons, Mars, threatens microbial communities that may inhabit fluvial channels located at the base of the volcano. There is no evidence to support the idea that microbes live in the channels. I am using microbes as an organism at risk to theoretical hazards. The channels are located near the west Olympus Mons escarpment, and formed as a result of cryospheric melting from heating by magmatic dikes (Basilevsky et al., 2006). These channels may be present elsewhere near the volcano, but have not been identified in the literature. At the base of the volcano, near the west Olympus Mons escarpment, glacial activity has been documented (Milkovich et al., 2006; Neukum et al., 2004) and may threaten microbes as the glaciers advance downslope, away from Olympus. Additional hazards to microbial communities include gravitational collapse of the volcanic flanks, rock fall events along steep escarpments, and lava flows.
Description of Hazards
River Channels - One hazard to biological communities living near Olympus Mons includes the generation of melt water at the planet’s surface, and the advancement of glaciers from the flanks of the volcano. Along the eastern flank of Olympus Mons, channels are interpreted to have formed from the erosion of surface units by water (Basilevsky et al., 2006). The close proximity of these channels with volcanic vents suggests to Basilevsky et al., (2006) that dike intrusion melted an ice-rich layer and mobilized large quantities of melt water to the surface. Crater retention ages indicate that the channel floors were last resurfaced ~4 Ma (Basilevsky et al., 2006) and is suggestive to Basilevsky et al., (2006) that Olympus Mons remained volcanically until the very recent geologic past. Melting by magmatic dikes may occur at other locations where ground-ice or surface-ice is present, and would be hazardous to any nearby biological communities.
Glacial Flow - The western
flank of Olympus Mons has many examples of lobate deposits that are interpreted
to be glaciers (Milkovich et al., 2006; Neukum et al., 2004). The glaciers
are not associated with any fluvial channels; however, channels may develop if
heat is supplied by dikes to melt the ice. In addition to melting of ice
sheets, the advance and retreat of glaciers would change the environment that
microbes inhabit near Olympus. On Earth, glaciers pluck rocks off the surface
as they advance, and deposit material during retreat. Glaciers would behave
similar on Mars and would be hazardous to the habitat that organisms living
near the flanks of the volcano.
Lava Flows - The generation
of large quantities of lava from Olympus Mons is unlikely to occur, though it
is a hazard worth considering here. Our current understanding of Mars suggests
that volcanism of the planet is shutting down, and volcanic activity at central
volcanoes, like Olympus Mons and Elysium Mons that were active between 100 Ma
and 4,000 Ma (Werner, 2009), have become largely inactive (Werner, 2009). In the past 100 Myr, small,
localized volcanic eruptions are the main form of volcanism on the planet (Werner, 2009).
Additional Considerations - Explosive
activity at Olympus Mons is unlikely, and is not considered in this report. The
volcano is not thought to erupt materials explosively [Werner, 2009], and there
is insufficient evidence for the presence of ice at the central vent of the
volcano to support this hypothesis [Bleacher et al., (2009)]. The presence of
ice would provide a source for volatiles, and provide a way for the volatiles
necessary for explosive eruptions. Also, there are very few studies that
investigate the dispersal potential of Olympus Mons. Theoretical treatments of
explosive volcanism have been investigated [Wilson and Head, (2007)], but not
applied to Olympus. There has yet to be a study regarding seismicity on Mars,
though seismic activity is likely to occur during eruptive phases of Olympus
Hazard levels
High Hazard Level
A high hazard level is applied to regions around Olympus where magma-ice interactions are expected to occur in the next 10 Ma, and where rock fall events are anticipated along steep slopes in the next 5 ka.
Intermediate Hazard Level
Effusive lava flows emanating from the central peak of the volcano are expected to occur in the next 100 Ma.
Low Hazard Level
Sector collapse (gravity driven collapse) is expected to occur if sufficient lava flows are erupted from the summit region of Olympus. This hazard may occur at some point in the next 100 Ma to 1,000 Ma.
A high hazard level is applied to regions around Olympus where magma-ice interactions are expected to occur in the next 10 Ma, and where rock fall events are anticipated along steep slopes in the next 5 ka.
Intermediate Hazard Level
Effusive lava flows emanating from the central peak of the volcano are expected to occur in the next 100 Ma.
Low Hazard Level
Sector collapse (gravity driven collapse) is expected to occur if sufficient lava flows are erupted from the summit region of Olympus. This hazard may occur at some point in the next 100 Ma to 1,000 Ma.
NVEWS Assessment
This volcano receives an NVEWS score of 0 because there is no real-time monitoring of the volcano. At present, the only form of monitoring is through remote sensing and there does not currently exist any seismic information for the planet. Olympus receives a few points in the scoring due to the presence of large quantities of ice, as are observed on the northwestern flanks of the volcano, and also due to the presence of channel networks that are thought to be carved by water melted from ice. The hazard factor is zero and the exposure factor is one. The required monitoring according to the scale provided is also zero. The volcano receives an aviation hazard level of zero because the max VEI at Olympus is zero, and there has been no activity in the past 5000 years.
Benefits of the Volcano
The volcano Olympus Mons brings fresh water periodically (every 25 million years or so) to the microbes living in the regolith on Mars. There are many nice aspects about being associated with such a large volcano as well, primarily fame and fortune. All of the other microbes want to live near Olympus Mons, and they are envious. We love our volcano and want to spend the rest of our days living in the regolith at the base of its flanks.
Hazards Mitigation
Barriers for the flow of water on the surface could redirect the water from hitting the microbial communities. This action would significantly help the efforts of the organisms to stay alive for the next 25 million years.
Volcanic Hazards Links
If you wish to learn more about Mars, I encourage you to download the free JMars software developed by Arizona State University. Please visit http://jmars.asu.edu/ for more information.
Also, if you suspect the region you live in is under attack by robots or volcanic hazards, submit a HiWish request and an orbiter might select an image from your requests to be get imaged! Please visit http://www.uahirise.org/hiwish/ for more information.
Also, if you suspect the region you live in is under attack by robots or volcanic hazards, submit a HiWish request and an orbiter might select an image from your requests to be get imaged! Please visit http://www.uahirise.org/hiwish/ for more information.