Alvin Rupes

Lobate scarps are one of the most common types of landform on Mercury, and frequently cross-cut impact craters of all sizes. However, the example in this image, termed Alvin Rupes, is one of only a very small subset of scarps that are accompanied by thin, linear depressions on their upper surfaces. One possibility is that these features are graben -- fault-bounded troughs that form when rock is extended -- like those seen in Caloris basin, for example. If so, then these graben are among the only such structures known to occur outside of volcanically flooded impact basins and craters.

This image was acquired as a high-resolution targeted observation. Targeted observations are images of a small area on Mercury's surface at resolutions much higher than the 200-meter/pixel morphology base map. It is not possible to cover all of Mercury's surface at this high resolution, but typically several areas of high scientific interest are imaged in this mode each week.

Date acquired: July 3, 2013
Image Mission Elapsed Time (MET): 15167012
Image ID: 4372157
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Center Latitude: 7.8°
Center Longitude: 151.1° E
Resolution: 54 meters/pixel
Scale: The crater in the center of the image is about 12 km (7.5 mi.) across
Incidence Angle: 75.6°
Emission Angle: 12.6°
Phase Angle: 88.2°
North is up in this image.

Photo credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington