C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes Geography S/07 Dr. Christine M. Rodrigue

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth 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 large regional features:  Tharsis and Elysium rises  The largest craters: Hellas, Argyre, Isidis, Utopia  Valles Marineris  The polar ice caps

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  The “Orders of Relief” for Martian Landscapes  The third order was the somewhat smaller major regions associated with the araeological eras:  In many ways, this is a cross-cutting category  It 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 Era  The Hesperian Era  The Amazonian Era

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  The “Orders of Relief” for Martian Landscapes  The fourth order is “in order” now:  These are smaller features (a few kilometers to a few hundred):  They are landscapes dominated by one or two processes  Fluvial valleys  Sapping alcoves  Linear fossæ  Folded and faulted mountains of Thaumasia  Lava tubes  Layered mesas  Patterned ground  Dune fields  Evidence of mass wasting

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly precipitation-fed overland and channelized surface flow  Echus Chasma (Mars Odyssey Themis)  Echus Chasma (Mars Express)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly precipitation-fed overland and channelized surface flow  Echus

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly alluvial fans and deltas  Melas

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly alluvial fans and deltas  Eberswalde Crater near Holden Crater

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly lake overflow channels  Ma’adim Vallis, pouring into Gusev Crater, where Spirit landed

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly lake overflow channels  Argyre, Holden, Aram craters and Ares Vallis  Nirgal Vallis tributary to that waterway, which still shows signs of water releases

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly jökulhlaup-like outflows  Kasei Vallis  Ares Vallis

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly jökulhlaup-like outflows  Ares Vallis  Aram Chaos and collapsed terrain

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly jökulhlaup-like outflows  Dao, Niger, and Harmakhis valles in Hellas Planitia

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Valleys dominated by fluvial processes:  Possibly jökulhlaup-like outflows  Chasma Borealis  Kathryn Fischbaugh and James Head created a topographic map and profiles and used them to estimate volume of a catastrophic melt (perhaps subsurface vulcanism): 26,000 km 3 !  Picked out deposits from such an event: could fill lowest portion of north polar basin to a few 10s of m!

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Alcoves, channels, aprons:  Groundwater sapping  Earth on right: Mt. St. Helens  Martian crater gully on left: MGS’ Mars Orbital Camera (~-55  at 18  )

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Alcoves, channels, aprons:  Groundwater sapping  Earth on top: sides of Houghton Crater, Devon Island, Canada  North of Baffin Island  Only Earth crater on a polar desert surface  Site of NASA- Houghton Project  Martian crater gully on left: MGS’ Mars Orbital Camera (where?)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Alcoves, channels, aprons:  Groundwater sapping  Fresh gullying  MGS’ Mars Orbital Camera

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Alcoves, channels, aprons:  Groundwater sapping  The triple point of water

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Linear fossæ and catenæ:  Extensional stress, faulting, downdropping of terrain between faults  Cerberus Fossæ

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Linear fossæ and catenæ:  Extensional stress, faulting, downdropping of terrain between faults  Claritas Fossæ

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Linear fossæ and catenæ:  Extensional stress, faulting, downdropping of terrain between faults  Alba Patera Fossæ

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Linear fossæ and catenæ:  Extensional stress, possibly with fluid extraction and subsidence  Tithonium Catenæ  Coprates Catenæ

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Linear fossæ and catenæ:  Secondary cratering from a primary impact event  THEMIS, +19  at 348  (Trouvelot Crater)  MOC, +16  at 325   Maybe a single object breaking up before hitting?  MRO image of Candor Chasma wall with this weird chain cutting across at an angle to gravity

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Folded and Faulted Mountains:  Grabens and folds  Thaumasia

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Lava Tubes:  Lava flows under a crust, which may collapse  Pavonis  Check out catena

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Layered Mensæ:  Resistant caprocks protect less resistant materials below  Cydonia and the Face on Mars

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Layered Mensæ:  Resistant caprocks protect less resistant materials below  Cydonia  Face with HRSC and MOC

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Layered Mensæ:  Resistant caprocks protect less resistant materials below  The heart on Mars south polar region, ~255 m across

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Yardangs:  Erosional æolian features  Classic sandblasting south of Olympus Mons taken by HRSC (Mars Express) near +6  by 220   Earth grooved terrain/yardangs (military source: location unknown)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Yardangs:  Erosional æolian features  Interesting parallel between Earth yardangs (again some unspecified military source) and Mars yardangs and layered terrain  The Mars yardangs (top) are from Æolis Mensæ, just south of Elysium on the margins of the southern highlands

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Dunes:  Depositional æolian features  Classic barchans in Nili Pateræ, a volcanic depression in Syrtis Major

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Dunes:  Depositional æolian features  Dune field in Endurance Crater imaged by Opportunity  Closest ridges < ~1 m  Blue color in slacks between dune crests reflect hæmatite blueberries  Lighter dust accumulates more on the lip of the crests than on the flanks  Like Earth star dune fields, probably reflect an unpredictable wind regime, as seen in this mystery military image (below)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Dunes:  Depositional æolian features  Uhhh, where IS Endurance Crater and its load of dunes?

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Patterned Ground:  Polygons and permafrost  Mars -72  at 29  (MOC)  Earth NW Territories, Canada, Sharon Johnson’s GeoImages, UC Berkeley  Stresses from:  Freeze-thaw of water  Expansion-contraction of other materials with temperature changes  Sorting of rock material in the polygon boundaries

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Patterned Ground:  Polygons and permafrost  Close up of boulders and other larger clasts caught in the boundaries among polygons

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Mass Wasting:  Landslides  Common on crater gully walls at a small scale  Very evident as a major mechanism for the expansion of Valles Marineris  Ganges Chasma  Noctis Labyrinthus

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Mass Wasting:  Landslides  Common on crater gully walls at a small scale  Very evident as a major mechanism for the expansion of Valles Marineris  South Candor Chasma

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Mass Wasting:  Chaos  Collapsed, jumbled terrain  May be source of massive outflows, possibly explosive if CO 2 is involved  Aram Chaos, which seems to feed into Ares Vallis

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Softened Craters:  Rims eroded  Burns Ridge (Opportunity)  Floors filled  Dust and ice (Mars Exp)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Softened Craters:  Rims eroded possibly by oceanic currents and processes before the northern lowlands dried out or were resurfaced with younger lavas  Ground penetrating radar (MARSIS on ESA Mars Express)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Softened Craters:  Floors filled  Water – alluvial fans in Eberswalde Crater (below)  Floors re-excavated by wind  Arabia Terra crater layers (to right)

C.M. Rodrigue, 2007 Geography, CSULB Mars: Fourth Order Landscapes  Softened Craters:  Floors REALLY worked over  Arabia Terra Crater (MOC)