地図
Online ISSN : 2185-646X
Print ISSN : 0009-4897
ISSN-L : 0009-4897
54 巻, 4 号
選択された号の論文の14件中1~14を表示しています
論説
  • 栗栖 晋二
    2016 年 54 巻 4 号 p. 1-16
    発行日: 2016/12/31
    公開日: 2018/07/01
    ジャーナル フリー

    The first precise maps of Japan were constructed from Inoh Tadataka's surveying project that had been made from 1800 to 1816. Inoh Tadataka's surveying group had made three types of maps (a large scale 1:36,000, a medium scale 1:216,000, a small scale 1:432,000). Such maps produced by this surveying group and its manuscript copies are called “the Inoh Maps” today, and a part of these maps remain at some museums, libraries in Japan and USA.
    At the University of Tokyo, 7 sheets of the Inoh Maps are preserved. These maps are ones on a medium scale 1:216,000, and the author will call them “Todai maps” in this paper. Todai maps are considered the same kind of ones as the latest set that were presented to the Edo Shogunate in 1821. Though a complete set of a medium scale in the latest Inoh maps consists of 8 sheets, Todai maps include only 7 sheets except 1 sheet of Kanto district. The origin and the history of them are obscure, because few related records have been found out yet.
    On the history of these maps, an interesting theory has been proposed since over 30 years ago. It is an idea that “5 sheets of them are a part of the important maps which were presented to the Meiji Government by the Inoh Family in 1874”. But it is generally believed that the maps presented then were all burned down in the Great Kanto Earthquake of 1923 when kept in Tokyo Imperial University. If this theory is true, Todai maps will be extremely valuable ones that were presented to the government of the day. Therefore, it is important to see if the theory is true or not. Fortunately, a medium scale's 8 sheets presented in 1874 were copied by the Imperial Academy in 1909 before the earthquake, and the manuscript copies remain at the Japan Academy now.
    In this study, comparing the contents by using the image data between Todai maps and the copies owned by the Japan Academy, the author ascertained if the theory can be really the case. And the following result was obtained:Todai maps can hardly be considered to be actually the maps that were presented in 1874, from the analysis of position and omission on place names in each map.

資料
  • 佐藤 剛, 横山 隆三, 土志田 正二, 田殿 武雄
    2016 年 54 巻 4 号 p. 17-22
    発行日: 2016/12/31
    公開日: 2018/07/01
    ジャーナル フリー

    This study introduces a case of interpreting landslide topographies with a constant vertical exaggeration stereoscopic slope map (CVES map). The map created by using digital elevation model (DEM) data shows 3D images of landforms as an anaglyph. We created two types of CVES maps by using the digital terrain model (DTM) from light detection and ranging (LiDAR) and the digital surface model (DSM) data of the Advanced Land Observing Satellite (ALOS) World 3D (AW3D) around Mt. Ebiradake in Northern Japanese Alps. We then compared these maps with a landslide distribution map created by using air-photo interpretation. As a result, we could clearly identify scarps, which were formed on the landslide body due to secondary landslide activity and were several meters relative height on the CVES map created using LiDAR DEM data with 5 m resolution. A number of scarps identified on the CVES map were difficult to interpret from the air-photo. The CVES map provides very helpful data for creating highresolution landslide distribution maps. In contrast, it was difficult to detect those scarps on the CVES map that were created from AW3D DSM data with 5 m resolution. However, we could identify landslides more than 200 m width and scarps more than 10-20 m relative height on the landslide body from the CVES map created by using AW3D DSM data. The AW3D data cover the entire world, so the CVES map created by using AW3D DSM data is useful for generating landslide distribution maps in the area where LiDAR data and/or air-photos are unavailable.

資料・添付地図解説
定期大会
特別講演
特別セッション
国際地図年(IMY)シンポジウム
ニュース
書評・紹介
添付地図
feedback
Top