Located on the slopes of Sif Mons, this area displays a simple sequence of events. The small shield volcanoes, features commonly found on Earth, are no more than 5 km (3 mi) in diameter. The dark background plains and the shield volcanoes both formed from the eruption of very fluid lava. Over time, several layers of lava flows covered each other, each one successively brighter, indicating that they became blockier in texture over time. The summits of the shield volcanoes protrude from the flows. Once the lava flows were in place, fractures formed as the new surface expanded.