Rille on a ridge! - Rima Ariadaeus

Seen here is part of the 300 km long channel (a rille) on the Moon called Rima Ariadaeus.

Rima Ariadaeus as captured by Apollo 10 astronauts from orbit. Source: NASA on Flickr

Unlike sinuous (curved) rilles which are volcanic in nature, linear (straight) rilles like Rima Ariadaeus are formed differently. The linear rille of Rima Ariadaeus is thought to have been formed when a section of the Moon's crust sank down between two volumes of rock. The following illustration makes it clear.

Sections of the crust sunk (called graben) between two adjacent volumes of rock. Image derived from Wikipedia. Credit: Jatan Mehta

In the featured image above, the rille is seen to cross the ridge from above it, which suggests the rille is younger than the ridge. The rille also cuts off some craters meaning it is younger than those craters as well. Finally, the rille itself has few craters on it. All of these suggest that Rima Ariadaeus is a relatively young lunar feature.