1 Insertion â when a base is added to the sequence. 2  Deletion â when a base is deleted from the sequence.  Copy number variation (CNV) is a type of mutation where large chunks of DNA are inserted, repeated or lost. These regions of DNA can be between 10,000 and 5,000,000 bases long.
Wind deposition can result in dunes and loess deposits.
In physical geography, a dune is a hill of sand built by either wind or water flow. Dunes occur in different shapes and sizes, formed by interaction with the flow of air or water.Most kinds of dunes are longer on the windward side where the sand is pushed up the dune and have a shorter slip face in the lee of the wind. The valley or trough between dunes is called a slack.A dune field is an area covered by extensive sand dunes. crescentic dune with a star dune superimposed on its crest is the most common complex dune. Simple dunes represent a wind regime that has not changed in intensity or direction since the formation of the dune, while compound and complex dunes suggest that the intensity and direction of the wind has changed.