Deltas are formed by constructive erosion.
deltas
Deltas are mostly made up of mud
Alluvial placers are those formed in present and past watercourses in gulches, creeks, rivers, flood plains and deltas.
Where a river which transmits a great deal of material arrives at the sea and there is little tidal range a delta will form. Example the Nile into the Mediterranean or the Mississippi into the Gulf of Mexico. The Amazon & the Congo, which flow into an Ocean, the Atlantic in these examples, do not form deltas because the ocean currents distribute the outflow of material into & along the ocean currents.
Beaches or deltas
The "sand dunes and deltas" are similar to that they are both "formed by weathering".
Deltas are formed by constructive erosion.
Deltas are created by deposition.
the word for that is deposition
They are formed by deposition of sediments from rivers and streams.
They have all been formed by Sandblasting
the sedamentic rocks formed on the gradual accumulation of sediments.
deltas
The Grand Canyon was formed mainly due to the Colorado river, and also due to uplift pronouncing the scale of the canyon; it is not formed due to a delta, as deltas are only formed at the mouth of the river, not in its middle course.
You could be thinking of a delta or abyssal plains.
They have all been formed by Sandblasting