I was able to get a couple of images of the Moon tonight before the clouds moved in. The rising Sun was just high enough to highlight several rima on the southeast edge of Mare Vaporum (Sea of Vapors). This image has north to the left and lunar east towards the top. The second image is annotated with some of the lunar features that are mentioned here.
The crater Hyginus appears to be one of the few craters not formed by impact. Without the raised rim common in impact craters it is thought to be a lunar volcanic caldera. The rille associated with the caldera runs some 220 km.
The rille nearer the top of the image is Rima Ariadaeus. This rille is thought to have formed when two parallel faults pulled apart and the surface between them dropped forming a graben. It is 300 km in length.
The final set of rille are the Rimae Triesnecker just east of the 25 km wide crater that gives the rimae their name.