Our transcription: Even after streams and rivers wear a landscape flat, it's possible for erosion to become active again if the landscape is uplifted, or if the regional base level drops. Geologists call this renewal of stream erosion "rejuvenation," and it produces certain characteristic landforms, such as "stream terraces" Stream terraces are found frequently in areas of very wide valleys where one of several things have happened. One of the most common ways in which terraces form is because of rejuvenation where there has been uplifting of the area or a down-dropping of the base level. So that a stream which was formerly meandering with big wide sweeping turns with a wide flood plain, ends up cutting into its own floodplain. Leaving the flood plain elevated on either side of the river as a terrace, so that it is no longer an active floodplain but actually an elevated surface above the river.
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