Linear depressions are densely distributed on the main divide of Akaishi Range. Recent studies conducted in other mountains suggest that such depressions are formed by the faulting which is controlled by the local stress field around mountain ridges. The distribution of linear depressions in the Akaishi Range, however, is strongly affected by the geological structure, thus it can not be explained only by the characteristics of the local stress field. In this paper, the distribution of linear depressions in the Akaishi Range is examined by considering the relation between the local stress field and the lithological characteristics of bedrocks.
The linear depressicns run parallel to the ridge-line and form either “twin ridges” or “uphill-facing scarps” on slopes near the ridge. Large number of linear depressions concentrate on the ridges whose long-axes extend in the directions of NNE-SSW or NE-SW, which are nearly parallel to the strike of bedding planes of Cretaceous sedimentary rocks of the Akaishi Range. Lithologically, most of linear depressions are located in the area made of shale.
Fault planes are found on some scarps limiting the linear depressions. Most of these depressions are considered to be formed by a normal faulting, judging from the lineations on the fault plane and the morphological features of the depression. As the fault plane almost coincides with the bedding, plane, it is certain that some faults occur along the bedding plane.
The fault planes limiting the linear depressions dip steeply upslope (45°_??_90°), nearly perpendicular to the gentle mountain slopes (0°_??_35°). This means that the normal faults are originated by the tensile stress whose direction is nearly parallel to the inclination of mountain slopes.
Some mechanical tests of rocks composing the Akaishi Range were carried out in the laboratory and the field, to evaluate the lithological effects on the tensile failure of rocks, The Brazilian test which is a kind of the indirect tensile test indicated that (1) among three major rock types of the Range, shale samples have the lowest tensile strength, (2) bedding planes of shale have the lowest tensile strength so that fractures can be formed most easily along the bedding planes, and (3) the lowest tensile stress is needed to form the fracture in the case that the axis of tensile stress is perpendicular to the dip of bedding planes. Field measurements by Schmidt rock hammer also proved that the shale showed the lowest values of hardness. These results suggest that tensile fractures which are initial forms of the normal fault, develop most easily on the mountain slopes whose inclinations are perpendicular to the dip of bedding planes of shale.
The lithological characteristics of shale in which the bedding planes have the least resistance to the tensile stress accounts for (1) the concentration of linear depressions in the Akaishi Range to the areas composed of shale, and (2) the existence of normal faults which are formed along the bedding planes in these depressions.

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This paper aims to estimate a long-term earthquake risk on the Japan islands from the data in “Active faults in Japan: sheet maps and inventories” (Research Group for Active Faults, 1980) and “Catalogue of historical damaging earthquakes in Japan” (Usami, 1975). The maximum magnitude of earthquakes, expectantly caused by active faults with Certainty I, is calculated from fault dimension using Matsuda's formula (1975). Seismic intensity (Japan Meteorological Agency Intensity Scale) is estimated for 161 grid points by Kawasumi's formula (1951). From recurrence interval of active faults, the probability (expectancy) in earthquake occurrence for arbitrary 1, 300 years is calculated. Accummulating the expectancy for each intensity scale, earthquake frequency per any 1, 300 years at each grid point is estimated. Considering the fact that earthquake motions with Intensity VI or higher have caused a great deal of damage in the historical period, it is adequate to discuss the earthquake risk based on the frequency of earthquakes with such intensities.
The earthquake frequency estimated from inland active faults is regarded as the inland earthquake potential, and it is compared with the frequency of historical earthquakes with the inland epicenter. Then the frequency of earthquakes in the future 1, 300 years is estimated, based on the idea that possibility of future earthquakes is high in the area where the earthquake potential has not been minimized sufficiently by historical earthquakes (Fig, 8)
In Japan, however, the damage caused by marine earthquakes has been very severe during the historical period. We must pay attention to such marine earthquakes particularly in coastal regions.

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The purpose of this symposium, held at the annual meeting of the Association of Japanese Geographers in March, 1985, was to discuss problems on the curriculum of geographical education for students of elementary and junior high school teacher courses in the faculty of education. The symposium included seven reporters and three commentators, together with many discussants. The following are the papers presented by the reporters:
SHIRAI, T.: Recent trend of taking courses by students in geography in faculties of teacher training.
TANAKA, K.: Geographic education in normal schools: the case of the Ikeda Normal School in 1930 s.
HIRASAWA, K.: Some problems on training of student teachers: a case of social studies in junior high schools.
YAJI, M.: Necessity of a curriculum on physical geography in faculties of teacher training.
KANAZAWA, T.: A methodological study on the map education in faculties of teacher training.
YAMAGUCHI, Y.: A methodological study on the curriculum of “methods of teaching in social studies” in faculties of teacher training.
NAKAGAWA, K.: A practical study on “teaching methods in social studies” in faculties of teacher training.
The commentators raised challenging questions, made constructive comments and led the discussion with attendants fruitfully. Discussions focused on the following points:
1. How to develop adequate curriculums on physical geography and cartography for students outside the geographical course in the faculties of teacher training.
2. Reconstruction of curriculum in normal schools may be necessary for the historical study of geographical education, and reevalution of them will give some ideas for geographical education today.

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