A satellite camera in space took this picture of northwestern Algeria, showing an impact crater, sedimentary
rock layers, and a stream channel flowing out of the crater. Algeria is at the northern end of the African
continent. The Algerian landscape includes a large portion of the Sahara Desert and two mountain ranges.
A. An ancient stream channel left deposits that built up over time to form the sedimentary rocks surrounding the stream. A meteorite's impact changed the direction that the stream flowed, which led to mountain ranges forming downstream from the crater.
B. Lava flows from volcanic eruptions created sedimentary rock layers; heavy rains formed a stream channel; and a meteorite's impact evaporated the stream water, leaving the area without a water source and creating a desert.
C. A meteorite impacted Earth, creating a low- lying area where water filled in to create a stream channel. The stream channel carried sediment with it, eventually forming the surrounding layers of sedimentary rock.
D. Layers of sediments were compacted to form sedimentary rock; a meteorite impacted Earth after the sedimentary layers were
formed; and water erosion formed a stream channel from the meteorite's impact zone.
