Mars: First Order LandscapesMars: First Order LandscapesSlide 3Slide 4Slide 5Slide 6Mars: First Order LandscapesSlide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 32C.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesGeography 494-01S/07Dr. Christine M. RodrigueC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesOn Earth, the orders of relief schemeIs sometimes seen in geography textbooksOrganizes topographic variation in a scale-dependent mannerGeographers often focus on Spatial analysis of particular phenomenaRegional synthesis to integrate assemblages of phenomenaScales at which processes and regional patterns operateThe interactions among phenomena at different scalesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesExamples of interactions among scalesIn spatial statistics: the Modifiable Areal Unit Problem (MAUP) In human geography: local cultural and political responses to global economic and political processes Biogeography: alpha, beta, and gamma measures of biodiversity Geomorphology: "megageomorphology" has emerged as remote sensing technology has made the simultaneous examination of form and process at large scale (small map scale) possibleC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesFor Mars, a handy descriptive scheme for handling the regional variations in Mars’ physical landscapesThe “First Order of Relief” = the crustal dichotomyThe northern lowlands: Vastitas BorealisThe southern highlandsIf Earth’s oceans evaporated (which they will …), there would remain a crustal dichotomy hereFormer ocean basins: low elevation, thin crust, basaltic, with a veneer of pelagic sedimentsFormer continents: high elevation, thick crust, granitic rocks and their extrusive igneous, sedimentary, and metamorphic derivativesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisRegional subdivisions:Utopia Planitia North Polar BasinEmbayments: Acidalia PlanitiaChryse PlanitiaAmazonis PlanitiaArcadia PlanitiaIsidis PlanitiaC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisRelatively young surfaceSmooth with few cratersThis is exactly what you’d expect if Mars had had an oceanIt could be expected to receive sediments from rivers, floods, and coastal processes and create terrigenous sediments nearshoreThey would be turned into minerals that would eventually precipitate out of the water column onto the abyssal floorThe oceans would thus cover the underlying original rock surface, much as pelagic sediments here doC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisFurther suggestions of an ocean:Drainage of Martian outflow channels and valley networksThis is also exactly what you’d expect if Mars had had an ocean to serve as base level for stream networksC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisDrainage:Valles Marineris' outflow channels, which drain into Chryse PlanitiaNanedis north of GangesAres and Aram Chaos Argyre to Aram and AresC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisEven better: Coastlines!?Transition between the southern highlands and the northern lowlands is quite abruptC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisEven better: Coastlines!?Terraces on the Arcadia side of Alba PateraC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisEven better: Coastlines!?Tim Parker’s analysis of Viking imageryC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisEven better: Coastlines!?Tim Parker’s analysis of Viking imagery (1994)His and others’ re-analysis using MOC imagery seemed to debunk his argument, which even he admitted in 2001But it’s as though the new imagery is so fine in resolution that it can’t detect the coarser scale at which this putative ocean’s coastline features might existMOLA suggests that, in fact, at least one of the “coastlines” is at the same elevation (water seeks a level constant with respect to the geoid)C.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisPlot complicationThat "ocean" floor is dominated by andesitic rockNot sediments with minerologies consistent with precipitation out of water. No carbonates! No ocean?C.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisAbout those andesites"Surface Type 1" (basalts dominating the southern highlands)"Surface Type 2" (andesites and andesitic basalts dominating the northern lowlands)C.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesVastitas BorealisRampart cratersC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian LandscapesThe Southern HighlandsMostly 1-5 km above the mean Martian geoid Versus 0-3 km below for the northern lowlandsSharp ~1 km scarp dividing the twoC.M. Rodrigue, 2007Geography, CSULBMars: First Order LandscapesThe “Orders of Relief” for Martian