Hydrogeomorphic effects of basin lithology on development of channel steps in first-order basins of the Ashio Mountains, Japan

Auteur(s) et Affiliation(s)

HATTANJI, T.

Fac. of Life and Environmental Sciences, Univ., Tsukuba, Japon

WASKLEWICZ, T.A.

Dep. of Geography, East Carolina Univ., Greenville, Etats-Unis

HAYAKAWA, Y.S.

Center for Spatial Information Science, Univ., Tokyo, Japon

WESTER, T.

Dep. of Geography, East Carolina Univ., Greenville, Etats-Unis

HEGI, Y.

College of Geoscience, Univ., Tsukuba, Japon

Description :
This study focuses on lithological contrasts of headmost channel morphology of 2 mountainous areas underlain by chert or sandstone. The areas have contrasting runoff processes : subsurface storm flow predominates in the chert area, whereas groundwater flow recharges stable stream flow in the sandstone area. Manual field measurements from sections of first-order streams and results of high-resolution analysis of long profiles using terrestrial laser scanning are discussed. The contrast in runoff processes, as well as grain-size distributions of weathering products between the 2 areas, influences dissimilar bed-load transport regimes and promotes spatial variations in channel profiles between headwater streams. These contrasting hydro-geomorphic processes affect channel-step morphology, indicating that lithology plays a key role in the formation of channel steps and in variations between headwater streams.

Type de document :
Article de périodique

Source :
Physical geography, issn : 0272-3646, 2012, vol. 33, n°. 6, p. 536-573, nombre de pages : 38, Références bibliographiques : 3 p.

Date :
2012

Editeur :
Pays édition : Royaume-Uni, Abingdon, Taylor and Francis

Langue :
Anglais