Journal of Geography (Chigaku Zasshi)
Online ISSN : 1884-0884
Print ISSN : 0022-135X
ISSN-L : 0022-135X
Volume 99 , Issue 7
Showing 1-9 articles out of 9 articles from the selected issue
  • Shuhan LIU, Shiro MAEDA
    1990 Volume 99 Issue 7 Pages 733-742
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    1. On the basis of tectonic lines, geological features and crustal movements, Fujian Province is divided into the three geological districts : north-west uplift, south-west depression and east volcanic depression districts. There are 6 deep and large fault zones, four of which run north-east (Sinian direction) and two of which run north-west.
    2. Caledonian granites are mainly found in the north-west uplift district and Variscan-Indosinian granites in the south-west district, but Jurasso-Cretaceous (Yanshanian) granites distribute in all of the three districts. Thus, Jurrasso-Cretaceous granites are most prominent in Fujian Province throughout the whole of the geological age.
    3. It is remarkable that the Jurasso-Cretaceous granites are closely related to the four fault zones running north-east. The intrusive and volcanic rocks, derived from the same magma source, took place in the similar tectonic environment and formed polygenetic intrusions. The magmatism was most active in the late Jurassic period with four intrusions.
    4. Cretaceous granites, emplaced mainly in the east volcanic depression district, compose of many kind of rocks such as granite, granodiorite, quartz diorite, monzogranite and so on. The intrusion in the Cretaceous period took place four times with miarolite granite comming into being in the third intrusion, but their granites show the same absolute age of 100-80 Ma by radioactive isotopes.
    5. Miarolite granite runs north-east from Shantou in Guangdong Province through east Fujian Province to Zhoushan in east Zhejiang Provice, and then across the East China Sea to Masan in South Korea. This is one of the most remarkable features of the geological structure of East Asia.
    6. Details of the petrological characteristics of Fujian Province are described in the paper.
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  • Kiyoshi KIKKAWA
    1990 Volume 99 Issue 7 Pages 743-758
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Inductively coupled plasma emission spectrometry (ICP) is applied for the chemical analyses of volcanic glasses to improve the efficiency of identification of widespread tephra.
    The differences of specific gravity and magnetic property among glass and minerals are effective for purification.
    The ICP method is very useful for routine analyses. The values of chemical analysis by the ICP are close to the EPMA data. The reproducibility is exellent, while fluctuation coefficients of most elements of tephra are about 5 %. Good correlations are found between the sum of major elements except of SiO2 and the refractivity of glass, and between the Fe/Mg ratio and the refractivity of orthopyroxene.
    Unique tephra in middle Pleistocene can be classified into two different groups of tephra by their minor elements Y and MnO. Tephra in north eastern Hokkaido are mainly came from two sources, which can not be distinguished in the field. The contents of incompatible elements of two types of tephra are clearly different. The source regions of Pliocene to Pleistocene tephra in Tokai and Kinki area can be estimated by the regional characteristics of their chemical compositions. The ICP method is also successfully applied for identification of submarine tephra in eastern Japan Sea, and correlation of sediments of Kanto to Kyushu areas and discovery of source of some widespread tephra in early to middle Pleistocene.
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  • Atsushi ONODERA
    1990 Volume 99 Issue 7 Pages 759-774
    Published: December 25, 1990
    Released: November 12, 2009
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    The purpose of this study is to identify boatmen's perception of the Abukuma River as a transportation route from old maps in the Edo era. While the old maps were prepared for specific purposes, they also reflect lifeworld of the people of the period. This study distinguishes expressions of the lifeworld from those for public purposes.
    Five old maps of the Abukuma River exist, which were drawn in different periods. Maps 1 and 2 cover the upper part, Maps 3 and 4 show the middle part, and Maps 5 presents the lower part of the Abukuma River. Maps 1 and 2 were prepared by merchants for channeling the river for navigation (Table 1). Map 3 was a planning map for river conservation and Map 4 is a copy of Map 3 in the later period. The purpose of Map 5 is unknown. Although the dates and purposes of the maps are various, they are all assumed to have been drawn by painters through the guidance of boatmen.
    The Abukuma River Maps are colored paintings on scrolls. The river was drawn in the way that readers could see from the upper to the lower part of the river as they open the scroll. The longest scroll is 13 meters, while the shortest one is 3 meters. Like many other river maps of the Edo era, in Maps 1, 2, and 5, landscape of the left side of the river was drawn upside down, while that of the right side was upside up (Plate 3). Maps 3 and 4, by contrast, were drawn from a bird's-eye view (Plate 6). Although the bird's-eye view map can present a three-dimensional view, drawing of some parts of the landscape behind mountains is difficult (Plate 4). In that case, the painter drew these mountains on a separate piece of paper and drew the landscape behind the mountains on the back of the paper ; he attached the piece of paper on the map so that the reader could see the back of the paper (Plate 5). The maps with this bird's-eye view are relatively few.
    Symbols of these maps contain general and thematic landmarks (Fig. 2). The general landmarks are common to all the maps, which include settlements, temples, shrines, tollhouses, trees, ferries, reefs, whirlpools, and shallows. The thematic landmarks are specific to each map, which include navigation routes, breakwaters, domains, and fields. Examinations of these symbols revealed that the thematic landmarks represented specific purposes of the maps. The basic landmarks, on the other hand, reflected perception of the painters and the boatmen.
    Expressions of dangerous spots as general landmarks, such as the one seen on Plate 2, reflect experiential perception of the boatmen. The expressions of dangerous spots are strongly related to their perception. The degrees of danger were indicated in letters as well as through distorted drawings.
    As the Abukuma River maps were not made through topographic surveys, a deviation of the distance on the maps from the real one gives us a clue to understand perceptual distance of the period. In Figures 3 through 6, the white sections on the side of the figures represent that they are expressed longer than the real distance ; the black sections are expressed shorter. In Maps 2 and 3, sections in the basins were drawn relatively shorter, while those in the V-shaped valleys were indicated longer (Figs. 4 and 5). In Maps I and 5, however, the perceptual distance has no relation with topography (Figs. 3 and 6). In general, the sections with many dangerous spots were drawn longer.
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  • Tatsuya YOKOYAMA, Satoshi MATSUNAMI, Kiyoshi OKUMURA
    1990 Volume 99 Issue 7 Pages 775-789
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
    Alluvial deposits in the Tokushima Plain in the study area are composed mainly of unconsolidated mud, sand and gravel, and show a considerable change of the lithofacies horizontally and vertically. The Alluvium can be divided into the Upper Mud (UM), the Upper Sand (US), the Middle Mud (MM), the Lower Sand (LS), and the Basal Gravel (BG) in descending order.
    The writers identified two volcanic ash layers in the Alluvial deposits with Akahoya Ash (6, 400y. B. P.) and Aira Tn Ash (21, 000y. B. P.), respectively, by an EPMA analysis from close resemblance of the chemical compositions of volcanic glasses.
    The formative process of the Alluvial deposits was discussed based upon the boring data, core samples, molluscan shells and their 14C-data.
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  • Eduard SULSTAROVA
    1990 Volume 99 Issue 7 Pages 790-795
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
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  • [in Japanese]
    1990 Volume 99 Issue 7 Pages 796
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
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  • [in Japanese]
    1990 Volume 99 Issue 7 Pages 796a-797
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
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  • 1990 Volume 99 Issue 7 Pages Plate1-Plate3
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
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  • 1990 Volume 99 Issue 7 Pages Plate4
    Published: December 25, 1990
    Released: November 12, 2009
    JOURNALS FREE ACCESS
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