1. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes Geography 441/541 S/14 Dr. Christine M. Rodrigue

2. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes The “Orders of Relief” for Martian Landscapes – The first order was the great crustal dichotomy: – Northern lowlands: ~ 1/3 – Southern highlands: ~2/3 – The second order was the conspicuous large features: – The largest craters: Hellas, Argyre, Isidis, Utopia – Tharsis and Elysium volcanic rises – Valles Marineris system of rifts and landslides – The polar ice caps – Syrtis Major windswept basalt plateau – Chryse Trough possible fluvial drainage system

3. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes The “Orders of Relief” for Martian Landscapes – The third order is what we're working on now: This is a cross-cutting category that addresses the “geological column” or relative ages of all Martian landscapes in terms of the three regional units that gave the three-part sequences of Mars’ evolution their names: – The Noachian Period – The Hesperian Period – The Amazonian Period

4. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes Noachian Era was discussed a few weeks ago – Oldest: – ~4.6 – 3.8 or 3.9 billion BP (or is it 3.5 billion?) – Earliest accretion, melting, differentiation of the planet – Era of bombardment (Earth’s Hadean times) – Intensely cratered with wide range of crater sizes – Some geomorphic erosion of craters – Establishment of and shutting down of planetary magnetic field – Some geological activity: – Valley networks – Volcanic activity (low viscosity flows, small pateræ) – Oceans? – Examples: – Noachis Terra– Terra Tyrrhena – Aonia Terra– Terra Sabæa – Terra Sirenum– Margaritifer Terra – Terra Cimmeria– Xanthe Terra – Promethei Terra –Tempe Terra

5. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes Hesperian Period was our last topic – Intermediate ages: – Most commonly from ~3.8 – 2.9 billion BP (or 3.5 - 1.8 billion BP) – Intense geological activity: – Shield vulcanism – Folding – Wrinkle ridges in lava covered landscapes – Faulting and formation of linear grabens in extensional zones – Gigantic outwash floods far past Noachian valley networks – Period in which climate began to dry out; dustiness increased; water evaporated, froze, sank into permafrost; acidic geochemistry – Examples: – Hesperia Planum– North Polar Deposits – Malea Planum– Isidis Planitia Basin Deposits – Lunæ Planum– Syrtis Major Planum – Chryse Planitia– Solis Planum

6. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes Amazonian Period is this week's topic – Youngest: – Most commonly from ~3.8 – 2.9 billion BP (or even 1.8 billion BP in some usages) to present – Much more peaceful geologically: – Some vulcanism – Oxidative geochemistry dominates – Some subsurface water releases and gullying – Some meteoroids continue to smack down – May even be obliquity-related ice ages – Extent and recency of these are energetically debated – Examples: – Amazonis Planitia– Arcadia Planitia – Utopia Planitia– Elysium Planitia – Dædalia Planum– North and South Polar Deposits – Acidalia Planitia– Lava flows on Tharsis & Elysium rises

7. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Amazonis Planitia:

8. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Elysium Planitia:

9. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Elysium Planitia: Cerberus Fossæ

10. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Utopia surfaces

11. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Utopia surfaces

12. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Adamas Labyrinthus: ice rich, possibly glacial

13. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Acidalia Planitia:

14. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Acidalia Planitia:

15. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Planum Boreum: North Polar Layered Deposits

16. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Planum Boreum: North Polar Layered Deposits

17. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes North & South Polar Layered Deposits

18. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Planum Australe: South Polar Layered Deposits

19. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Planum Australe: South Polar Layered Deposits

20. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Arcadia Planitia

21. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Arcadia Planitia http://www.ingo-paulussen.de/pictures.htm

22. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Lavas of Tharsis and Dædalia

23. C.M. Rodrigue, 2014 Geography, CSULB Mars: Amazonian Landscapes Lavas of Tharsis and Dædalia

24. C.M. Rodrigue, 2014 Geography, CSULB Mars: Third Order Landscapes The “Orders of Relief” for Martian Landscapes – Thus concludes our consideration of third order landscapes: These are large regions that are subtly different from one another, marked by differences in crater density, crater alteration, and geomorphic evidence of processes that dominated particular periods on Mars I used this scale to discuss and illustrate the three major periods of Mars' geological history – The Noachian Period – The Hesperian Period – The Amazonian Period – On to the finer scale features of the fourth order