GEOL 1121 Lecture Notes - Lecture 6: Olympus Mons, Hydrothermal Vent, Divergent Boundary
17 Mar 2018
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Document Summary
Volcanism is common on some of the terrestrial planets and moons. ~20 x volume of largest terrestrial volcano. Largest volcano is solar system: 18 km high, 600 km diameter. Olympus mons compared to the largest terrestrial volcanoes hawaiian islands. Many samples from the moon are lavas. Smooth dark plains ( maria ) are lava flows no large volcanic mountains. Active volcanoes are concentrated along plate boundaries; volcanic activity along mid- ocean ridges not shown. ~10% volcanism intraplate, hot spots, continental rifts. ~75% volcanism at divergent boundary (spreading ridge) Mid-atlantic ridge breaks ocean surface at iceland. Icelandic basalts commonly erupt from fissures linear crustal fractures and this is the style of volcanism along mid-ocean ridges. Eruption occurs at a central valley at the top of the mid-ocean ridge and new ocean crust is formed. The narrow central valley of the mid-atlantic ridge is visible here . Note hot springs black smokers and white smokers aka hydrothermal vents .
