Geochemical database of Japanese islands based on published domestic data: standardization of data and high-precision location coordinates
Abstract
As for the international database recording geochemistry data, GEOROC and PetDB mainly involving seafloor data are managed. The progress of the data-driven science by increasing computer performance can deal with a large number of parameters with a large quantity of data. As for heterogeneity of the mantle structure (e.g. Iwamori and Nakamura, 2015), the world-wide scale of the geochemical heterogeneity is discussed on the basis of these databases. However, these databases have the problem of lack of unity of data format. Particularly, the progress of the analytical technique greatly improved the accuracy and precision of data, though the various precisions of data are mixed in the compiled geochemical database. For example, wet chemical analysis was mainly used for bulk chemistry until the 1970s where iron content was separately reported as Fe2+ (FeO) and Fe3+ (Fe2O3), but after the 1980s, X-ray fluorescence method has been widely used where iron was treated as only FeO (total) or Fe2O3.
Furthermore, the location coordinates of the many data in international databases are described as the representative position of the geologic map of the original articles, and thus the resolution of these location data can represent only the order of degree unit. This precision may have no problem for the discussion of world-wide scale, while interpretation in the detailed spatial scale may not be possible. We constructed new database "DODAI" providing the data which overcome these problems (Haraguchi et al., 2018: http://dsap.jamstec.go.jp/DODAI/index.html). This database focused the data published in the Japanese domestic journals and bulletins. This database has converted the sampling position of individual geochemical data into the GPS-familiar location coordinates, i.e. latitude and longitude, by image-based geocoding and improved the positional accuracy drastically compared to the previous databases. This precision allows us to correlate sample positions to the correct geological units described in the digital geologic map such as the Seamless Geological Map (AIST). In this presentation, we will describe the concept of DODAI dataset and discuss the potential usage of such dataset in the geochemical study.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.V11C..15H
- Keywords:
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- 1099 General or miscellaneous;
- GEOCHEMISTRY;
- 1916 Data and information discovery;
- INFORMATICS;
- 1942 Machine learning;
- INFORMATICS;
- 3699 General or miscellaneous;
- MINERALOGY AND PETROLOGY