Boulders In The Sea Of Serenity

A wrinkle ridge in western Mare Serenitatis is littered with boulders and high-albedo (bright) areas. Image is ~1.5 km across, NAC M106826896L [NASA/GSFC/Arizona State University].

A wrinkle ridge in western Mare Serenitatis (23.448°N, 8.058°E) is one of many in the region that exhibits a high boulder density and high albedo (bright) summit areas. But it isn't the only place this relationship is seen! These bouldered ridges are also observed in Oceanus Procellarum, Mare Humorum, Mare Cognitum, and Mare Nubium, to name a few. Scientists are still uncertain as to why some ridges have these features and others don't, and why this isn't observed along the entire ridge. This ridge seems to be eroding along its slope, rather than the crest, suggesting that the material is coming from the ridge itself. In addition, a small impact crater (red arrow in below image) has excavated boulders and high albedo material, making it more likely that the source is from the ridge and not a product of distant cratering events.

Larger view showing a crater (red arrow) that has excavated the same material that is eroding out of the ridge. Image is ~2.3 km across, NAC M106826896L [NASA/GSFC/Arizona State University].

There are two ways to describe high albedo on the Moon: either freshly exposed rock and soil, or material with different composition or properties. It is uncertain which description is best for the high albedo observed along these ridges or whether it is a combination of the two. If the boulders and high albedo material have happened because of tectonic activity, then that implies that activity along mare wrinkle ridges has occurred more recently than previously thought. These features need to be studied in more detail in order to fully understand what role they play in lunar history. This is just one of the many surprises that LROC has revealed!

WAC monochrome mosaic at 100 m/pixel. Here, the location of the wrinkle ridge in Mare Serenitatis (red arrow) is shown in relation to the Apollo 15 landing site (yellow star) [NASA/GSFC/Arizona State University].

To view the ridge in more detail, look at the top of the full LROC NAC frame!

Related Posts:
Bright ridge near Mons Hansteen
Constellation Region of Interest in Mare Tranquillitatis
Buckland Boulders
Wrinkle Ridge Near Montes Teneriffe


Posted by Renee French on January 09, 2013 09:06.