Abstract
Reddish weathered gravels are well found within Quaternary fluvial deposits in Japan. Such gravels are also generally softened. To understand the formation process of such gravels included within Quaternary fan deposits, both degree of color and softness of gravels, and their spatial distribution have been measured using some color and physical indices. As a result, the reddish grade which is one index of chemical weathering decreases as the penetrative strength of gravels degreases with the depth from the fan surface. Decrease of specific gravity and increase of porosity were also recognized in the same extents.
This means that change process in color may be closely related to physical/kinetic changes within gravels. However, compared with spatial distribution of reddish color in some places, the reddish distribution may also be strongly controlled by water table within the deposits.
