1 / 25

Geologic evolution and cratering history of Mercury

Geologic evolution and cratering history of Mercury. By: G. Neukum, J. Oberst, H. Hoffmann, R. Wagner, B.A. Ivanov Presented by: Kristin Hepper. Global mosaic of Mercury. Facts about Mercury. Closest planet to the sun Mercury  36.2 million miles from the sun

henry
Download Presentation

Geologic evolution and cratering history of Mercury

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Geologic evolution and cratering history of Mercury By: G. Neukum, J. Oberst, H. Hoffmann, R. Wagner, B.A. Ivanov Presented by: Kristin Hepper

  2. Global mosaic of Mercury

  3. Facts about Mercury • Closest planet to the sun • Mercury36.2 million miles from the sun • Earth92.96 million miles from the sun • Smallest planet • Radius 1,500 mi • Earth’s radius 3,959 mi

  4. The Sun and planets drawn to scale The relative radii of the Sun and Planets

  5. Daytime 750 K (890.33 F° ) Nighttime 90 K (-297.67 F°) Temperature • Largest range of temperature of any planet

  6. Geologic Features • Appears lunar-like • Covered with impact-craters • Vast smooth plains • Low density of impact craters

  7. Densely cratered (highlands) Lightly cratered (low-lands) Mercury’s Terrain:2 major types

  8. Highlands • High abundance of large craters • Overlapping • Up to tens of kilometers across • Inter-crater plains • Gently, smoothly-flowing units • Characterized by few craters < 15km in diameter

  9. Crater 100km across

  10. Oldest geologic units on Mercury… • Densely cratered terrain • Inter-crater plains • Age based on impact craters and their corresponding materials

  11. Multi-ring structure Caloris

  12. Low-land plains • Where are they found? • In and around large multi-ring structures • North polar region • Patches in highlands

  13. Origin of low-lands • Volcanic  favored or • Caused by ejecta emplacement

  14. Similar to lunar counterparts Morphology more complex the greater the diameter gets Craters • Crater = a saucer-shaped pit or depression caused by impact

  15. Craters cont… • Simple  Complex crater dimaeter • 10.3 kilometers • Age of craters This crater is 10 km wide

  16. Tectonism on Mercury • NOT tectonically active TODAY • But was active in the past • How do we know? • Lineaments • Lobate scarps • Volatile deposits

  17. Lineaments • Linear topographic features of regional extent • Believed to reflect crustal structure • Ex fault lines, aligned volcanoes, straight stream courses

  18. Lobate Scarps • Represent thrusting events • Caused by rapid cooling and contraction of planet • 550km • Heights vary from 0.1-2km

  19. Seen as bright spots in polar areas Reflected radar signal is similar to water-ice deposits on earth No seasons occur on Mercury So temperatures at poles are stable < 135 K Volatile Deposits Volatile- adj. Evaporating readily at normal temperatures and pressures

  20. Composition of Mercury • IRON • Unlike other terrestrial planets • Concentrated at core • Multispectral images from Mariner 10 • Smooth plains • Dark-blue albedo areas

  21. Geophysical • Due to tidal forces, spin rate slowed • Faulting in the lithosphere • Also see compressional features

  22. Mercury’s endogenic processes have long since ceased Similar to both the earth and the moon Bombardment history Lunar-like Since ~ 3.0Gya cratering has dropped off Mercury now experiences a constant level of bombardment Conclusions

  23. Conclusions cont… • Experienced tectonic activity in the past • Little is known about the surface composition

  24. Future Missions to Mercury • 2009 by ESA • Bepi-Columbo • Includes a lander

More Related