THE GEOLOGY OF NEW ZEALAND 17 



streams, and has accumulated to a depth of 20 feet or more in 

 suitable situations. Bones of the moa are found in these deposits. 

 Recent movements. — Since the epoch of great differential dis- 

 placements of relatively small earth-blocks, which was the essential 

 character of the "Pleistocene" orogeny, there have been a series of 

 relatively small movements involving much larger earth-blocks, 

 which movements have been elevation, depression, or tilting. 

 Exceptionally localized differential movement has resulted in 

 fault-coasts or strongly warped surfaces. Between these move- 

 ments were long periods of crustal stability during which the 

 cycles of erosion reached a fairly advanced stage. Hence along 

 the coast in different districts there are marked raised beaches, 

 while extending far up the valleys are rock-benches or alluvial 

 terraces, indicating that the valleys are not monocychc but were 

 rejuvenated from time to time. 



