1969 Volume 21 Issue 1 Pages 23-29
Well-developed coastal terraces are observed along the Ôma Promontory. The terrace surfaces inthis region are classified into five levels : 1st 150-160m, 2nd 90-110m, 3rd 45-50m, 4th 35-40m, and 5th 10-20m in height. The base of the 1st level is composed of the hard shale, while the bases of the other four levels are composed of soft shale. Most of these five terraces are dissected, but there is seen a bit of flatness in the / 1st level. The 2nd level is distributed in a larger area and it is tilted to the west. The area is dotted with the fragments of the 3rd level, each of them being very small. The 4th level is well-developed and is tilted to the southwest. The 5th level has no evidence of tilting and it has developed diagonally against the 4th level.
The tilting movement in this area has made a unique change in the form of the terraces which made it more difficult to classify them.