Ius Chasma
Ius Chasma's Floor
PSP_009368_1720  Science Theme: Landscape Evolution
This image spans the floor of Ius Chasma’s southern trench. Ius Chasma is located in the western region of Valles Marineris, the solar system’s largest canyon. This canyon is well known for its fine stratigraphic layers modified by wind and water.

The outcrops contain interchanging layers of dark and bright rocks. The layered deposits consist of dark basalt lava flows and bright sedimentary layers. The sediments are likely to be from atmospheric dust, sand, or alluvium from an ancient water source. The layers are visible on the gentle slopes above the canyon floor, in pitted areas, and in small mesa buttes. The floor of the canyon is littered with megaripples that are aligned in a north-south direction.

Ius Chasma is believed to have been shaped by a process called sapping when water seeped from the layers of the cliffs and evaporated before it reached the canyon floor. This process is thought to have dominated during the Amazonian period.

Ius Chasma also has several structural features such as east trending normal faults and grabens that deformed the canyons. Recent geomorphological events include mass wasting (avalanches) and minor sapping from gullies that continued to erode the canyon walls.

Written by: Circe Verba  (3 September 2008)
Acquisition date
26 July 2008

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
265.6 km (165.1 miles)

Original image scale range
26.7 cm/pixel (with 1 x 1 binning) so objects ~80 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
60°, with the Sun about 30° above the horizon

Solar longitude
103.9°, Northern Summer

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  39.6°
Black and white
map projected  non-map

IRB color
map projected  non-map

Merged IRB
map projected

Merged RGB
map projected

RGB color
non-map projected

Black and white
map-projected   (942MB)

IRB color
map-projected   (450MB)

Black and white
map-projected  (481MB)
non-map           (509MB)

IRB color
map projected  (188MB)
non-map           (448MB)

Merged IRB
map projected  (245MB)

Merged RGB
map-projected  (237MB)

RGB color
non map           (419MB)
B&W label
Color label
Merged IRB label
Merged RGB label
EDR products

IRB: infrared-red-blue
RGB: red-green-blue
About color products (PDF)

Black & white is 5 km across; enhanced color about 1 km
For scale, use JPEG/JP2 black & white map-projected images

All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible:

NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona.