Volcanism in the Solar System Part 1 Inner

Volcanism in the Solar System Part 1: Inner Solar System Justin Filiberto Lunar and Planetary Institute

Plan of Talk 1. Earth - review 2. Inner Solar System • • Mercury Venus Moon Mars 3. Outer Solar System • • Io Enceladus Titan Triton 4. Summarize Volcanoes in the Solar System

Earth’s Shield Volcanoes

Earth’s Composite/Stratovolcanos

Shield vs. Composite

Earth’s Volcanoes • • • Cinder Cone Caldera Complex Lava Flows Tuff Ring And many more…

Mercury • • • Mercury Earth From Sun (AU) 0. 39 1. 0 Mean radius (km) 2434 6371 Mass (1024 kg) 3. 30 5. 98 Surface T (K) 340 295 Gravity (m s-2) 3. 7 9. 8

Mercury Volcanoes Seen by Messenger Spacecraft more to come…

Mercury

Venus • • • Venus Earth From Sun (AU) 0. 72 1. 0 Mean radius (km) 6052 6371 Mass (1024 kg) 4. 87 5. 98 Surface T (K) 735 295 Gravity (m s-2) 8. 9 9. 8

Venus Surface Landers: Venera & VEGA

Sapas Mons • 400 km across, 1. 5 km tall • Slope ~ 0. 5° • Very long flows • What type of Volcano?

Maat Mons • JPL Press Image 20 x Vertical Exaggeration • Unexaggerated … • What type of Volcano?

Pancake Domes • Single Flows, Steep sides • Height 1/2 - 1 km. • What kind of volcano? • What kind of lava?

Pancake Domes • Rhyolite? • Or merely cold, crystal-rich basalt? • What kind of volcano? • What kind of lava?

? • Low cones in flat lava plains • A few km diam. (5 km for inset) • What type of lava? • What kind of volcano?

Venus vs. Earth

Moon • 1/3 diam of Earth • 1/6 gravity • Dark, low, mare plains.

Mare Plains

Channels

Domes • Gruithuisen domes • 20 km across, 1. 2 km tall. Avg ~7° slope; steepest ~20°. • Are these volcanic? • If so, what are they most like on Earth?

Gruithuisen Domes

Mars • • • Mars Earth From Sun (AU) 1. 5 1. 0 Mean radius (km) 3386 6371 Mass (1024 kg) 0. 642 5. 98 Surface T (K) 227 295 Gravity (m s-2) 3. 7 9. 8

Olympus Mons • 640 x 840 km across • 21 km tall • Avg slope 5° • What kind of volcano? • What kind of lava?

Lava Flows on O. M. 1 <-- - - 3 km - - -->

Tharsis Tholus • 150 km across • 8 km tall • What kind of volcano? • What kind of lava?

On Syrtis Major, a Shield Volcano • Small Hill • Steep Slope, ~30° • Surrounded by thin lava flows • What is it?

On Syrtis Major, a Shield Volcano • Broken Cinder Cone?

Inner Solar System Summary • • What features? Types of volcanoes? Lava compositions? Similarities? Differences? Generalities? What types of volcanoes are common to the Earth only? Why? • What types of volcanoes are common in the inner solar system? • What does this suggest about the cooling histories of the inner planets?

Some questions to ponder • What types of volcanoes are common to the Earth only? Why? • What types of volcanoes are common in the inner solar system but not the outer? Why? • What does this suggest about the cooling histories of the inner planets? Outer planets?

Some questions to ponder • From the volcanoes we have seen which ones would we expect on which planets? • What do they suggest about other planets? • Since most of us do not live near a volcano, how can students connect volcanoes on the Earth and other planets?