Surface Features on Mars

Dr. Joshua BandfieldMars Space Flight FacilityArizona State University

Mars has Many Types of Surface Features

• Impact Craters

• Volcanic Features

• Fluvial/Water-Related Features

• Layers

• Aeolian/Wind Features

2

Crater Ejecta

• Material that gets thrown out of a crater when a meteorite hits the surface– Sometimes looks

rougher than the surrounding terrain

Crater in Elysium Planitia 18N, 136ECrater in Elysium Planitia 18N, 136E

All THEMIS visible imagesAll THEMIS visible imagesare ~18 km acrossare ~18 km across

Most THEMIS images are Most THEMIS images are taken during the afternoon taken during the afternoon and the sun is shining from and the sun is shining from the left side of the imagethe left side of the image

7

Rampart Craters

• Have distinct ejecta that looks like it flowed across the surface– Probably due to ice or

liquid water in the subsurface when crater formed

Rampart Crater in AcidaliaPlanitia 28N, 319E8

Crater Morphology

• Morphology (shape) will look different based on age and size:– Large craters: Central peaks, rings

and/or slumping walls– Old craters: Eroded and have

‘softer’ features

• 3 ‘types’ of craters:– Preserved– Modified– Destroyed

Central Peak

Slumps

Arabia Terra 18N, 6EArabia Terra 18N, 6E9

Modified Craters

• Craters can be eroded or modified by:– Wind– Water– Lava

Ares Vallis 16N, 330EAres Vallis 16N, 330EOrcus Patera 16N, 183EOrcus Patera 16N, 183E

10

Volcanic Features

• Many types of surface features are associated with volcanoes:– Volcanic structures– Lava flows– Calderas– Lava Tubes/Channels

Olympus Mons 18N, 230E (Wide Angle)Olympus Mons 18N, 230E (Wide Angle)13

Olympus Mons (shown here) is a shield-like volcano the size of the state of Arizona!

Volcanics on Mars• Volcanic activity

has dominated the surface of Mars

• Tharsis is a huge (1/3 of the planet) volcanic region that consists of 3 shield-like volcanoes

• Olympus Mons, Alba Patera and other small volcanoes are evident in this area

Ascraeus Mons

Pavonis Mons

Arsia Mons

Alba Patera

Olympus Mons

14

Lava Flows

• There are many lava flows on Mars of all ages– These are similar to lava flows

that we see in places like Hawaii, but can be much larger!

Daedalia PlanumDaedalia Planum-26N, 232E-26N, 232E15

Apollinaris Patera Caldera

THEMIS Day IR Mosaic

Lat: 9.3 S Lon: 174.4 E

Multiple basins in the caldera

Channels along the flank

618

Dust Devil Tracks• Dust devils pick dust up in to the atmosphere

– They can act like vacuum cleaners and leave dust-free tracks behind them

Argyre PlanitiaArgyre Planitia-47N, 318E-47N, 318E35

Wind Streaks

• Wind streaks form behind topographic features (such as crater rims)– Dust can be deposited or

scoured in a wind streak

Syrtis Major 0N, 72ESyrtis Major 0N, 72E36

Dunes

• Dunes are wind blown piles of sand– Sand dunes on Mars are

often dark because they are made of basaltic sand

Sand Dunes in Kaiser CraterSand Dunes in Kaiser Crater-47N, 19E-47N, 19E37

Surface Features on Mars

• Impact Craters

• Volcanic Features

• Fluvial/Water-Related Features

• Layers

• Aeolian/Wind Features

39

Mars Maps• Mars Regions • Zoom in to see details

• Also see: http://pubs.usgs.gov/imap/i2782/i2782_sh1.pdf

40