1982 年 1982 巻 7 号 p. 11-20
The Japanese group of the IGCP Project 163 IGBA has been constructed to participate in the generation of an international data base of igneous rocks in the world. Geochemical major element data of the Japanese Quaternary volcanic rocks, which were compiled and managed by ARAMAKI and UI with a small DBMS of a mini-computer system, were analyzed as an example to show how to use the data base in petrology. The analytical system is composed of SPSS and TSAM; the former was used not only for statistical analysis but also for data modification, and the latter was for a trend surface analysis by using two-dimensional moving average method. Several descriptive statistics were calculated to evaluate the data, and cluster and factor analyses were performed to clarify the data structure. The Japanese Quaternary volcanoes were dividen into five areal groups, and the grouping was tested by computing canonical discriminant functions. It is assumed that these groups don't perfectly refrect geochemical composition, but distribution of several groups show interesting patterns for volcanic petrology.