Geographical Review of Japan

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The aither believes that the present research on the Jubusen block mountains is an important step in clarifying the structure of many other blocks in the Kinki District and the mechanics of their building. The results obtained by the author's research are summarized as follows:
1) The Jubusen fault scarp is a conspicuous scarp lying along the southeastern margin of the Jubusen block mountains which are situated on the southwestern corner of the Koga Plateau. Together with the Ide fault scarp along the western and the Gonokuchi fault scarp along the northern, they are recognized to be a tilted horst of triangular outline.
2) The Jubusen fault scarp makes the front of the tilted horst, and its fault plane represents a transitional form gradually from reverse fault in the north to overthrust in the south, and further, we find an empirical formula between the relative height (H) of the fault scarp and the declivity (θ) of the fault plane as follows, 11=2.5 (θ+52)
3) The Isle fault scarp was formed by a normal fault, resulting in three benches due to step fault, and afterwards modified with warping which is also recognized along the eastern margin of the Nara Basin as its continuation.
4) Under the Jubusen fault scarp we can find four levels of river terrace, and under the Ide fault scarp also four of terraced fan. They are all of polygenetic origin, and caused by intermittent warping as above mentioned.
5) In this area, faulting occured after early Pleistocene, while warping occurred after late Pleistocene.

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