Using the name “block deposition feature” which has no implication of particular formation processes for so-called block streams, this study analyzed the morphological characteristics of a block deposition feature near Mt. Yokone on Kobugahara Plateau in the northern part of the Ashio mountains, composed of granodiorite. The block deposition feature is located in a valley head. A few streams spring out from the both sides of the block deposition feature, and seeps under the blocks. After detailed survey of longitudinal and cross sections and plan forms of the block deposition feature, the feature is divided into the three segments: A, B, and C. Segment A and C show narrow forms and thin block deposits, while segment B is wide with thick block deposits. There are some lobes on Segment B. Segment A and C are run-ways of blocks and segment B is a zone of block deposition. It is indicated that core stones moved on slopes. Since there are some lobes on Segment B, slow mass movement may have played a role in its formation.

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Pollen analysis, radiocarbon dating and facies analysis were carried out in two cores obtained from Yachidaira Mire, Yamagata Prefecture, Northeast Japan. From the results of pollen analysis, four local pollen zones were established, namely, YD-1, YD-2, YD-3, and YD-4 in ascending order. The local vegetation changes going back to approximately 22, 000yrs BP reconstructed from those pollen zones are as follows. YD-1 zone: subboreal coniferous forest accompanied by Betula abundantly, YD-2 zone: Transition zone from subboreal coniferous forest to cool temperate deciduous broad-leaved forest, YD-3 zone: cool temperate deciduous broad-leaved forest composed mainly of Fagus, YD-4 zone: cool temperate deciduous broadleaved forest including Pinus and Cryptomeria.
Radiocarbon dates were obtained from the two cores of Yachidaira Mire. The date of uppermost part of YD-1 zone is 22, 570±240yrs BP (TH-2037). The dates of middle part of YD-3 zone are 3, 380±20 (NU-1430), 4, 260±50 (TH-2035), and 4, 700±40yrs BP (TH-2036).
Lithofacies and frequencies of herbaceous pollen and fern spores indicated that peat bog was formed at least three times between ca. 22, 000yrs BP and the present at Yachidaira Mire.

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In the eastern foot area of the Suzuka range, central Japan, there are several reverse faults trending mainly N-S, which constitute the eastern margin of Kinki Triangle Area. It is well-known that some of them in this area are active in the late Quaternary time, but precise tectonic landforms on each faulting, especially in the Holocene time, were not well constrained by previous studies. The author have investigated to clarify detailed topographic features formed by a reverse fault and distributions of active faults during the Holocene time in this area on the basis of interpretation of large-scale aerial photographic analysis and leveling topographic profiles.
The eastern boundary of the Suzuka range is delineated by a fault zone. In the northern part of the fault zone, frontal faults are still active in the late Holocene. On the other hand, faults constituting in the middle to southern parts of the fault zone have not displaced Holocene terrace surfaces. From these points, there is difference on faulting between the northern part and the other parts in the fault zone at least in the late Holocene.
The Kuwana and Yokkaichi faults that delineate the western boundary of the coastal plain have been active as reverse faults during the late Pleistocene to the Holocene. Furthermore, both of them have displaced the latest Holocene terrace surfaces.
The Ichinohara fault extending to approximately E-W has also been active in the Holocene time and deformed late Holocene terraces surfaces. Moreover, at least two faulting events have occurred since about 4, 000yr. B. P..

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