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Research paper : The advanced geological researches and fundamental national land information (M. Saito)−16−Synthesiology - English edition Vol.3 No.1 (2010) 4) environmental matters (e.g., groundwater flow, underground disposal of radioactive and hazardous waste);5) academic information for investigation of regional geological evolution (e.g., the process of formation of the Japanese Archipelago, changes in the environment, compilation of seamless geological maps);6) provision of a standard for investigating the detailed geology of Japan at the district level.In Japan, geological maps have been produced since the mid-1800s. Initially, the main objective was the development of domestic resources. During the period of rapid Japanese economic growth in the 1950s and 1960s, identification of limestone resources suitable for use in cement was given high priority. Today, although one of the major emphases is on defining resources such as stone for use as aggregate and identifying hot springs, geological maps are used to satisfy other basic and diverse societal needs. They provide information that can be used to mitigate damage caused by earthquakes and volcanic eruptions. They can be used to identify unstable ground conditions, to determine safe locations for industry (e.g., nuclear power stations), and to select disposal sites for waste materials. They are important tools for geological consultants who need to understand the local geology in the areas of their projects. Recently, geological information has been used as a resource for tourism. Geoparks have been established throughout Japan where people can visit interesting geological formations. Geological maps also provide companies with basic information for use in business continuity plans that can minimize disruptions to their business activities following natural disasters. The effects of the use of geological maps described above can be divided into two categories: those that add to the economy (e.g., identification of resources), and those that reduce costs within the economy (e.g., reduction of the costs of disaster recovery). Each GMJ 1:50,000 sheet is not initiated with any one of the above specific uses in mind. The decision to survey the Tomochi 1:50,000 sheet was made with the primary objective of developing a comprehensive and accurate representation of the geology of the entire district. However, the knowledge and information gained from the survey are used directly by society or through specific-purpose geological maps developed from the survey data (Fig. 2). The former Technology Information Department at AIST stated that the characteristic outcome of geological maps “fans out widely from the Geological Survey of Japan”[7].4 Methodology for creating the GMJThe development of a geological map is not a deductive research project. No experiment is performed to confirm a hypothesis. It uses an inductive method, where truth is determined from observations of strata and rocks exposed in a particular area. During a geological survey, a geological model of the area is created in the researcher’s mind on the ABC1 kmFig. 3 Example of the changes in the geological map. Example of GMJ 1:50,000 “Yokoyama” district [revised from Reference 8].A: Geological map created in the 1960s[9]The concept of an accretionary complex was not incorporated.B: Surface geological map created in the 1990s[10]This map was created without sufficient time for an adequate survey.C: GMJ Yokoyama 1:50,000 sheet published in 2000[11]

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