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C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
Geography 441/541S/14
Dr. Christine M. Rodrigue
C.M. Rodrigue, 2014Geography, 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, 2014Geography, 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, 2014Geography, 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 km):• They are landscapes dominated by one or two processes
– Fluvial valleys – Sapping alcoves– Outwash channels– Linear fossæ– Folded and faulted mountains of Thaumasia– Lava tubes – Layered mesas – Patterned ground – Wind abraded/etched landscapes– Dune fields – Evidence of mass wasting
C.M. Rodrigue, 2014Geography, 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, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Valleys dominated by fluvial processes:– Possibly precipitation-fed
overland and channelized surface flow– Echus
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes• Valleys dominated by
fluvial processes:– Possibly precipitation-fed
overland and channelized surface flow (L to R)
– Terra Sirenum
– Warrego Vallis, in Thaumasia Highlands
– Nanedi Vallis
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes• Valleys dominated by fluvial processes:
– Possibly lake overflow channels– Ma’adim Vallis, pouring into Gusev Crater,
where Spirit landed– Elsewhere on Nanedi Vallis– Nirgal Vallis west of Chryse Trough
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes• Valleys dominated by fluvial processes:
– Possibly alluvial fans and deltas– Melas
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Valleys dominated by fluvial processes:– Possibly alluvial fans and deltas
– Eberswalde Crater near Holden Crater
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes• Valleys dominated by fluvial processes:
– Possibly lake overflow channels: non-equilibrium systems– Argyre, Holden, Aram craters, Ares Vallis– Ma'adim upland lakes to Gusev?
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes• Valleys dominated by fluvial
processes:– Possibly jökulhlaup-like outflows
– Kasei Vallis– Ares Vallis
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes• Valleys dominated by fluvial
processes:– Possibly jökulhlaup-like outflows
– Ares Vallis– Aram Chaos and collapsed terrain
C.M. Rodrigue, 2014Geography, 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, 2014Geography, 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 km3!
– Picked out deposits from such an event: could fill lowest portion of north polar basin to a few 10s of m!
C.M. Rodrigue, 2014Geography, 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, 2014Geography, 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, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Alcoves, channels, aprons:– Groundwater sapping
– Fresh gullying– MGS’ Mars Orbital Camera
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Alcoves, channels, aprons:– Groundwater sapping
– The triple point of water – Ways around that little
issue:– Deep elevations– Fluids with lower freezing
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Linear fossæ and catenæ:– Extensional stress, faulting, downdropping of terrain between
faults– Cerberus Fossæ
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Linear fossæ and catenæ:– Extensional stress, faulting, downdropping of terrain between faults
– Claritas Fossæ
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Linear fossæ and catenæ:– Extensional stress, faulting,
downdropping of terrain between faults– Alba Patera Fossæ
C.M. Rodrigue, 2014Geography, CSULB
Mars: Fourth Order Landscapes
• Linear fossæ and catenæ:– Extensional stress, possibly with fluid extraction and subsidence
– Tithonium Catenæ– Coprates Catenæ