Gullied Crater (Released 26 August 2002)

Scaled Image

Image Credit: NASA/JPL/ASU

About this image

This image is from longitude 164W (196E) and latitude 40.7S, and is found in a heavily crater region of the southern hemisphere. The most prominent landform in this image is the large crater in the center. The dark region in crater floor is a shadow, and one can detect the shape of the crater rim from this feature. In the lower crater wall, one observes gullies. Mars Global Surveyor's Mars Orbiter Camera (MOC) first observed gullies and scientists have suggested that they result from fluid flow on martian slopes. The most accepted hypothesis for the formation of gullies is via release of a fluid at the intersection between a layered bedrock outcrop and a steep crater or valley wall located at the middle and high martian latitudes. Gullies consist of three main features: the head alcove, the channel, and the apron. The head alcove appears to form by mass wasting of material from above. Fluid is released from within a slope and causes sediment to collapse down slope. The channel runs down the slope from the base of the alcove. Finally, the apron is the resulting deposit of debris that traveled down the channel. Gullies are thought to be the youngest geologic landform in most places where they occur.

Please see the THEMIS Data Citation Note for details on crediting THEMIS images. 


Image ID: 
V02403003 (View data in Mars Image Explorer)
2002-06-30 01:51
Mon, 2002-08-26
1186 pixels (20 km)
3079 pixels (52 km)
0.017064 km/pixel
0.017188 km/pixel


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