Landforms were eroded and built on a scale very similar to those now forming, but at a slightly higher level. Interglacial coastal sediments were vegetated, weathered, soil- covered, blown away, or dissected by erosion. As the sea has returned almost to its previous level, it has partly reoccupied the coastal zone of the last interglacial age. If the Pleistocene deposits had been lowered only a few meters by tectonic subsidence or erosion, they would have been reworked by Holocene coastal processes and buried by Holocene deposits. In other places, Pleistocene barrier beaches or wave-cut cliffs are separated by only a low scarp or step down to their modern analogs.
Few coasts preserve the record of interglacials older than the last one.
Numerous examples are cited in the Plate captions for this chapter. Figure 6.1 . Worldwide distribution of tectonic coastal and shelf types. No classification of coasts is widely accepted because the forms are almost always compound in their origin. He recognized the global impact of the Holocene rise of sea level and distinguished primary coasts as those that had simply been drowned with minimal modification by marine processes and secondary coasts as those that were subsequently modified by marine erosion or deposition.