Geological Chronicle
Rimae Opelt is a lunar graben structure spanning 55 kilometers in length across the lunar basalt crust. Formed by structural faulting and crustal extension, the trench cuts through terrain within the Montes Riphaeus quadrangle (LAC-76).
Officially cataloged by the International Astronomical Union at selenographic coordinates -13.6432° latitude and -18.1382° longitude, the rille designation notes: Named from nearby crater.