著者

Shunji OUCHI

出版者

The Association of Japanese Geographers

雑誌

地理学評論 (ISSN:13479555)

巻号頁・発行日

vol.79, no.5, pp.179-197, 2006-04-01 (Released:2008-12-25)

参考文献数

35

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Seven small offset streams crossing strike-slip faults in central to south-western Japan, longitudinal profiles and channel course geometry of which were measured in the field, show no correlation between the amount of channel offset (offset length) and drainage area or channel length above the fault. The method to estimate fault slip rates from the relationship between offset length and channel length above the fault seems not valid for these offset streams. The angle of deflection, which is the angle between the fault line and the reach connecting reaches divided by fault displacement (offset reach), shows a negative correlation wi offset length for the streams of long offset, while no correlation is clear for the streams of short offset. When the channel offset is short and significant channel shift towards the steepest possible course does not occur yet, fault zone width probably controls the deflection angle. The negative correlation for the streams of long offset may reflect the easier channel shift of the streams with shorter offset among them. The deformation types of these offset streams are judged as Type A (offset slope of fault displacement is smaller than channel gradient) except for one as Type C with larger offset slope. Some configurations characteristic to the deformation types still remain in their longitudinal profiles with various degrees of fluvial adjustment. Offset streams seem to be in the repeated process of tectonic deformation and fluvial adjustment as long as the fault actity continues.

著者

Shunji OUCHI

出版者

The Association of Japanese Geographers

雑誌

Geographical review of Japan, Series B (ISSN:02896001)

巻号頁・発行日

vol.69, no.2, pp.126-133, 1996-12-01 (Released:2008-12-25)

参考文献数

52

被引用文献数

2

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Recent studies of fluvial processes, slope processes, hydrogeomorphology, rock control and weathering processes indicate that studies of process geomorphology in Japan increasingly deal with phenomena in smaller scales of time and space. Precise measurements of the movement of water and materials and of rock properties are required as a basis for discussion. This implies that geomorphology is joining the circle of modern sciences, although belatedly, and this trend will be accelerated in the near future.