Mars vs Earth Planetary showdown of the ages: Volcanic style
Mar’s biography• Mars formed 4.6 billion years ago, within the same time as Earth’s formation.• Mars is the second smallest planet, and about half the size of Earth.• Mars has the largest volcanoes of any of the eight planetary bodies, including their satellites • It has the second highest number of volcanoes; Venus has the most.• Mars’s gravity is only 38% of Earth’s, which results in its large volcanoes
Mar’s Composition• Maintains similar geologically stratified levels as Earth, but has larger crust relative to size• Core is mostly iron with a small amount of nickel• Does not have tectonic plate movements, unlike Earth • However, Tharsis rise (uplift bulging in western hemisphere) indicates that some divergence must have happened within the crust• No distinct land and oceanic features; instead, the topography varies differently
Volcanism on Mars• Because Mars has such large and distinctvolcanoes, different provinces weredemarcated: • Tharsis Volcanic (Western hemisphere) • Elysium Volcanic Provinces (West of Tharsis)• Other notable volcanoes include: • Syrtis Major • Highland Paterae
Mars • Olympus Mon • The caldera • Tharsis Ridge • Ascaraeus Mons • Pavonis Mons • Arsia Mons
Olympus Mons• Of all the volcanoes on Mars, the tallest volcano is Olympus Mons: • Located in Tharsis volcanic province (western hemisphere of Mars) • Shield volcano • 21 km high and 550 km across • 100 times greater in volume than Earth’s largest shield volcano: Mauna Loa • Roughly the size of Missouri • Formed from continental hotspot • When it was active, it had spewed large amounts of gas into the atmosphere, inferring that Mars once had a thick amotsphere
Reasons for Mars’s Large Volcanoes• Volcanoes of such magnitude were able to form on Mars is because the hot volcanic regions in the mantle remained fixed relative to the surface for hundreds of millions of years.• Mars no longer has active tectonic plate activity, which allows volcanoes to be active for centuries without tectonic disturbance• Due to no movement of crustal drifting, the volcanic hot spot remains under the same mountain resulting in extremely large mountains, such as Olympus Mons• Mars have deeper and larger magma chambers, due to having less gravitational buoyancy on magma
The Hotspots• Volcanoes on Mars are much wider and taller than Earths, but have similar ratios of height to base radius
Tectonic Movement and formation of Volcanoes on Mars• Mars is a much smaller geologically active world than Earth• It is less tectonically active, it does not have any drifting tectonic plates• Mars does not have crustal drift, the volcanic hot spot remains under the same mountain resulting in extremely large mountains, such as Olympus Mons
Tectonic Plate Movement and Formation of Volcanoes on Earth• Most volcanoes form near convergent plate boundaries, such as the Pacific Ring of Fire (68% of Earth’s Volcanoes)• Earth’s hot spot theory on volcano formation • Oceanic divergent plate boundaries • Continental convergent plate boundaries • Earths “hotspots”
Mars•Red areas shows the North magnetic fields•Blue areas shows the South magnetic fields
Citations• Hamilton, C. (1995). Martian volcanoes. Retrieved from http://www.solarviews.com/eng/marsvolc.htm• Tayfun Oner, A. (1997). Retrieved from http://www.solarviews.com/cap/mars/voly1.htm• Greetings from mars. (n.d.). Retrieved from http://abyss.uoregon.edu/~js/ast121/lectures/lec12.html• Wilson, Lionel; Head, James W. (1994). "Mars: Review and Analysis of Volcanic Eruption Theory and Relationships to Observed Landforms". Rev. Geophys. 32(3): 221–263• Solomon, Sean C.; Head, James W. (1982). "Evolution of the Tharsis Province of Mars: The Importance of Heterogeneous Lithospheric Thickness and Volcanic Construction". J. Geophys. Res. 87 (B12): 9755– 9774.
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