As a result of field mapping and aerial photograph and map interpretation, maps and tables of late Quaternary displacements at the Hikihashi and Kitatake Faults are presented. Both faults, exhibiting clear topographic displacements, are Certainty I features according to the classification of MATSUDA et al. (1977).
The Hikihashi Fault, upthrown to the south, is interpreted as dominantly right-lateral, with thrusting in the east (fault strike 100°east of north) and graben development in the west (fault strike 120°). The Kitatake Fault, upthrown to the north-east, is dominantly right-lateral, with a probable thrust component.
Tabulated data show the Hikihashi Fault has an average horizontal displacement rate of at least 2m per 1, 000 years and vertical displacement rate of about 0.5m per 1, 000 years. The Kitatake Fault has an average horizontal displacement rate of more than 3m per 1, 000 years and vertical displacement rate of more than 0.4m per 1, 000 years. Both faults, using Matsuda's 1977 classification, are thus Class A active faults, with net slip rates of greater than 1m per 1, 000 years. Ratios of horizontal to vertical displacement allow calculation of the principal shortening direction as about 161°(or 341°) east of north.
A comparison of recorded seismicity in Miura Peninsula with estimated recurrence intervals for transcurrent faults suggests there could be movement at an active fault in the peninsula within a few hundred years.

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Ten characteristic tephras since Latest Pleistocene time were recognized in the North Hakkoda Mountains. Tephras HK-a, -b, -f, -i and -j of them were correlated to the previous reported Tomakomai ash (Tm), the upper fall unit of Towada-a ash fall (To-a), Chuseri pumice(Cu), Hachinohe pumice(HP) respectively. Tephra HK-i was correlated to the pumice-flow tuff(HPf) of the upper part of HP. The local pollen assemblage zones in four sites, Yachi, Tashiro and Kenashitai moors and Jigokunuma, were identified and correlated based on their stratigraphy and chronology. In ca. 12, 000-8, 500 years B. P., two transitional forest stages from the Latest Pleistocene subarctic coniferous to the Holocene cool-temperate Fagus forests, i.e., the Betula or Alnus forest stage and the deciduous broad-leaved forest one mainly characterized by plentiful Quercus (Lepidobalanus) in ascending order. In the latter half of the Betula or Alnus forest stage, a temporary expansion of the subarctic conifers was recognized. Fagus spread out rapidly since ca. 8, 500 years B. P. In the altitudes over ca. 1, 100m, subarctic Abies mariesii began to expand in ca. 5, 000 years B. P.

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