Author carried out this study for clarifying topographical characteristics and verifying scale of natural phenomenon in the places indicated by the “Shizensaigaidenshohi” (monument of natural ...disaster). The followings are the major results.1) Clarification of topographic characteristics where a “Shizensaigaidenshouhi” stands or indicates.Most of the place where “Shizensaigaidenshouhi” (monument of natural disaster, simply referred to as “the monument” in this article) stands or indicates, locates not only in very low areas (e.g. flood plain), but also in a little bit higher areas (e.g. natural levee). This is because the monument building was not reasoned by heavy rainfall or flood itself, but by the damage of lives or properties which exist in higher areas.2) Verification of scale of natural phenomenon which brought disaster where a “Shizensaigaidenshouhi” stands or indicates.Past flood depth inferred by the description of the subject monuments was slightly low or equal to that estimated by modern hazard map. In early and middle of the 20th century, many flood disaster happened and the relevant monuments were built thereafter, but in the late 20th century, the number of severe floods which recorded in the monuments decreased. However, frequency of heavy rainfall is increasing recently. This suggests flood disasters likely to be recorded in the monuments would occur again in the near future.These results show that location of a “Shizensaigaidenshouhi” stands or indicates prefers a little bit higher areas as people lives more in such areas compered to lower land and also show that past flood depth inferred by the description of the subject monuments was compatible with that estimated by modern hazard map.Map symbol “Shizensaigaidenshohi” is recently introduced to the basic topographic maps, and the new topographic maps therefore provide people with new map reading experience, which might raise people's awareness of disaster prevention as existence of “Shizensaigaidenshohi” is deeply relating to topography.
Current discussion for the revision of the Courses of Study in geographic and cartographic area strongly recognizes the importance of studies of those areas. Especially, the interim report published ...in August, 2015 that showed the direction of the revision of the Courses of Study suggested that the new curriculum temporally called “Chiri Sogo” which means comprehensive geography, is needed for senior high school’s education to develop skills to solve various issues. Although the importance of geographic and cartographic educations for pupils and students are strongly recognized, antipathic tendency for learning those areas broadly observed among these children. Author shows antipathic tendency of geographic and cartographic study by analyzing Courses of Study Implementation Survey done by NIER （National Institute for Educational Policy Research）, MEXT （Ministry of Education, Culture, Sports, Science and Technology） in 2001, 2003, 2005 and 2012.Observed tendencies are summarized as follows: 1) Antiparhtic tendency and hardness of understanding for areas, “land”, “industry” and “trade” were recognized from elementary school ages and those problems became stronger in junior high school.2）Although there's a strong relationship between pupils' and students' favorable impression and understanding, there's a gap between degree of understanding and favor, especially in social studies at elementary school in 2003 and geographic studies at junior high school in 2001. However, this gap is observed not so much from other researches.3）Although teachers' impression about difficulty of learning among history and geography was not so different, the degree of junior high school students' understanding geography was much lower than history. Even though many topics of geography were felt easy by teachers, students often felt hard to understand.4）There's a difference in degree of antipathy and misunderstanding among senior high school students that might come from difference of their eagerness for further learning. Antipathic tendency for learning application of maps were observed for both groups compared to other geographic topics.5）Antipathic tendency for field study around school area is strongly observed among high school students. This tendency might be come from specific problems in high school education.The reason of the gap among the degree of favorable impression and the degree of understanding might be explained by shortage of teachers who majored geography at universities they graduated. Previous studies suggested that teachers who didn't major geography might not teach geography enjoyably. The studies also suggested such tendency could be much stronger in application of maps.The attractive curriculums for teachers majored history or other subject except geography should be made and also efforts for attracting people to geography and cartographic area are needed not only in school education but also in various ways.Notice: This report is made from authors' individual experiences on geographic and cartographic studies, and the report doesn't mean MEXT's （Ministry of Education, Culture, Sports, Science and Technology's） official positions.
Applying interferometric SAR (InSAR) analysis using ALOS/PALSAR data to inland crustal earthquakes in the Fukushima-Hamadori area, we succeeded in mapping a ground displacement associated with the
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7.0 earthquake that occurred on 11 April, 2011. The most concentrated crustal deformation is located ~20 km west of the city of Iwaki, showing displacements away from the satellite with ~2.2 m at the maximum. Clear displacement discontinuities are recognized with an offset of ~1.6 m at the maximum, which are just on the Shionohira, Idosawa and Yunotake faults. From field surveys, we found that earthquake surface faults appeared with a vertical offset of ~1.9 m, consistent with the InSAR observation, and their locations correspond to the discontinuities in the interferogram. We inverted the InSAR data to construct slip distribution models, and our models show (1) nearly pure normal fault motions (2) on west-dipping planes (3) with moderate-dip-angles (50–65°). The inferred west-dipping normal fault motion on the Yunotake fault is correlated with the present-day topographic features, consistent with the idea that the historically-repeated normal faultings have developed the topography. On the other hand, for the Shionohira and Idosawa faults antithetical relationships are presented, maybe suggesting that large normal faultings have been infrequent historically.
Tsunamis brought by large earthquakes and floods brought by heavy rainfalls suffer us for long years. Recent disasters like tsunami caused by the 2011 off the Pacific coast of Tohoku Earthquake and ...flood by heavy rainfall in Sep. 2015 still remain on our memory as many lives were lost.Although detection of flooded area is relatively easy to grasp through aerial photographs, other optical or radar observations, investigation of flooded depth in large area is very difficult because the data are basically collected by on-site surveys and those surveys require a lot of time.On-site surveys of tsunami flooded depth are basically operated by surveying tsunami marks on buildings walls or trees. Tsunami marks are remained by muddy water or floating matter. For instance, tsunami marks by muddy water can be observed like horizontal lines. Also, tsunami marks by floating matter can be observed as damages on buildings. Flooded depth mapping can be easily done if information of those marks can be collected more speedy and more effectively.Geospatial Information Authority of Japan (GSI) recorded tsunami damage images of the 2011 off the Pacific coast of Tohoku Earthquake. We tried tsunami flooded depth measurement from the Mobile Mapping System (MMS) images in order to hand down to posterity by using MMS for mapping of tsunami flooded depth widely on the 2011 off the Pacific coast of Tohoku Earthquake. MMS was expected to be able to collect a lot of tsunami mark images for a short time.MMS images through Sendai plain to Ishinomaki plain were taken in April 2011, and Southern Sanriku area to Northern Sanriku area were taken in May 2011. In other words, the images were collected for one or two months after the earthquake. Tsunami flooded depth data were collected at 873 points through MMS image analysis, and flooded depth at 77 points measured by MMS could be identified on-site. On-site surveys were conducted in 2011 to 2013.Results are as follows:1) By mapping of tsunami flooded depth data in a wide area, overview of distribution of tsunami flooded depth can be grasped, and mapping result might be used for evaluation of geomorphological effect for variation of tsunami flooded depth.2) Tsunami flooded depths measured from MMS images correspond well with on-site survey. 88% of flooded depth measurement points which were both analyzed by MMS images and surveyed on-site, supposed to measure the same tsunami flooded marks.3) Tsunami flooded depth measurement from MMS image is very useful way for collecting flooded depth data as the measurement is very accurate and a lot of marks of tsunami flood can be collected speedy and effectively.MMS image analysis for flooded depth measurement might be effective not only for tsunami, but also for heavy rainfall. If more dense data can be collected by MMS image, contours of flooded depth can be drawn more correctly and precisely. Accumulation of studies on flooded depth might contribute to reveal mechanisms of flood occurrence.Notice: This report is made from authors' individual experiences on geographic and cartographic studies, and the report doesn't mean MEXT's (Ministry of Education, Culture, Sports, Science and Technology's) official positions.
The Geospatial Information Authority of Japan (GSI) supports victims and regions affected by the 2011 off the Pacific coast of Tohoku Earthquake, by promptly surveying and providing geospatial ...information such as maps and aerial photos. In particular, the “Tsunami Flood Area Overview Map” is useful for various geographical analyses of tsunami damage. This paper summarizes the results of analyses of the relationships between tsunami damage interpreted by aerial photos and geographic conditions such as land condition, elevation and land use. Based on our GIS-based overlay analyses of relationships between tsunami damage levels and other geographic data such as inundation depth, landform classification, elevation and land use, the following are clarified: 1) damage levels are closely related to inundation depths; 2) completely destroyed areas are located within 1 km from the coastline; 3) differences in landform and land use of coastal areas influence the damage level of the hinterland area.
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