The Musashino Uplands in Tokyo, investigated frequently by many researchers for the last 90 years, are composed of Musashino and Tachikawa alluvial fans of MIS 5.3 to MIS 3 and Shimo-sueyoshi marine terraces of MIS 5.5.

Recently, a GSI 5m digital elevation model was opened to the public. It is a useful tool to analyze the precise classification of landforms, and provides us with new maps like the Red Relief Map (by T. Chiba), a new erosion map (by T. Chiba), and the RC Map (by Y. Suginaka), contributing to a revised view of landforms in the Musashino Uplands with 1m accuracy.

Second, a great number of digitized boring data and analyzing tools have been developed. We have used more than 2,000 data sets in the western Musashino Uplands. These data revealed the shallow-underground geology continuously.

Third, recent progress in tephrochronology allows us to analyze cryptotephra for age determination of fan gravels in research cores at important site of fan surfaces. Those new conditions enable us to renew the division of landforms in the Musashino Upland as follows.

During MIS 7, the Paleo-Tama River formed the older stage Musashino alluvial fans (K surface).

During MIS 6 to MIS 5.5, Tokyo Formation and S marine Surface were formed by the transgression.

During MIS 5.3, fluvial delta sediments made the Narimasu Surface (key tephra : On-Pm1).

After MIS 5.3, probably MIS 5.2, 5.1 and MIS 4, the Paleo-Tama River formed the Musashino alluvial fan of the younger stage.

The main surface (M1a and M1b ; key tephra : Hk-OP) of the Musashino alluvial fan formed in MIS 5.2-5.1. From MIS 5.1 to MIS 4, M2a (key tephra : YP) was lower than M1. M2b (key tephra : Hk-MP) was lower than M2a. M2c and M2d formed after M2b. M3 surface (key tephra : Hk-TP, BCVA), the lowest one among the M surfaces, formed in MIS 4. The formation of a series of M2a to M2d oblong surfaces, may be a response to the step-like sea-level lowering during MIS 5.1 to MIS 4.

After MIS 4, the Tachikawa alluvial fan of the later part of the Younger Stage of the Musashino alluvial fan developed, eroding the headward part of the Musashino alluvial fan completely.

This paper reviews studies on the Quaternary tectonics and geomorphic processes of the Ryukyu arc, southwestern Japan. The Ryukyu arc lies along the subduction zone between the Eurasia and Philippine sea plates. Many islands of the Ryukyu arc are classified into volcanic islands, accretionary complex islands and uplifted coral reef islands. The Quaternary tectonics forms many strike-slip and normal faults in the Pleistocene limestone (Ryukyu group) originating from coral reef sediments. Mountains and hills consisting of metamorphic and sedimentary rocks are eroded, reflecting the rate of weathering controlled by various environmental conditions. Previous physiographic studies considered several landforms as tropical and subtropical landscapes, whereas such landforms should be reconsidered in terms of geological factors as well as climatic ones. The authors suggest that future studies require a more comprehensive and integrated understanding of the geomorphic processes involving both the climatic and geological factors.