Vol.3 No.4 2011

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Research paper : Investigation of the distribution of elements of the whole of Japan and their applications (N. Imai)−271−Synthesiology - English edition Vol.3 No.4 (2011) vacation over five years. At this time, the sample treatment was planned to be completed to the greatest extent possible in the field. The most important consideration was to finish the sieving and drying in the field. Fine-grained sands were separated by sieving them with river water. Then chemical analyses were conducted using ICP emission spectrometry. Thereafter, automated neutron activation-analysis was used to analyze many elements simultaneously. The analyzed elements were 26 elements such as cobalt, chromium, copper, nickel, phosphorus, lead, uranium, and zinc. This research project was extremely important because the geochemical mapping of large areas was done for the first time in Japan. However, because it required a huge amount of work from sampling to analysis, it was important to allocate individual roles and to work appropriately.4.1.2 Geochemical map of Japan (Development by converting the mode of thinking)After the project of mapping the northern Kanto region, we sought to extend the area of the geochemical map to the whole country. However, because the same method in the northern Kanto region would have to be applied similarly, we were unable to continue the project. Because the area of Japan is about 380,000 km2, the necessary number of samples would become 380,000 as 1×1 km mesh. Because such a huge amount of time and cost were deemed necessary to achieve the project, nobody would take the group’s appeals seriously, even when proposed. Meanwhile, the work to produce the geochemical map around Sendai[12] and Yamagata City[13] was continued, although the area was quite small. As the sea area, the geochemical map was also formed in the coastal area from the Noto Peninsula to the seas off Akita[14].The major turning point came from a discussion on the topic of whether a nationwide geochemical map was truly impossible. Although it seemed infeasible because the project needed funding and staff on an enormous scale, it was suggested that the mode of thinking should be reversed. First Fig. 3 Formation of the geochemical map of Japan and a scenario for opening access to the publicComponents and key basic elements to support the geochemical map and the final goalFig. 4 Development of research in producing a geochemical mapFrom the geochemical map of the northern Kanto region (1991) to a geochemical map of the land and seaCrust surfaceBasiccharacteristicsCompletenessReliabilityOperabilityFormation of geochemical maps of land and seain Japan and their openingto the publicElemental abundanceKind of elementProcessing of sampleChemical analysisRepresentativeness ofsamplesMedia to the publicKind and collectiondensity of sampleSystem of researchand analysisDrawing and standardization of dataStandardization ofmethodFactors ofconstituentesIntegrationandcompositionFinal goalLand, SeaElemental distributionUserconvenienceRegional geochemical mapConstruction of methodologyGeochemical map ofpriority areasConstruction ofmethodology forspecific subjectMethodology conceivedfrom the purposeCompletion of nationwidegeochemical mapNorthern Kanto region (1991)Sendai City (1997)Sea of Japan (1997)Land (2004)Sea (2009)Land and sea (2010)Development togeochemical map ofland and seaUse of sample andinformation accumulatedin the field of geology, AISTCompletion of nationwidegeochemical mapof land and seaFirst in the worldExertion of the collectivestrength of AISTConversion of thinkingfor nationwidegeochemical mapEnvironmental Prizeaward (2005)

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