| 内容記述（抄録等） | 1)Since the summer of 1982, a few samples of Cenozoic rocks have been collected for the paleo/rock magnetic study from the westcentral Kyushu Island; mainly at the Amakusa Isles district. Most of all data obtained on these rocks were already reported previously(Domen&Muneoka,1982,Muneoka&Domen,1983).In this report, the data newly obtained afterwards and also the previous ones mentioned above are summarized. Some more additional data will be appeared in the near future.2)Fig.1 is a map showing the sampling sites in this area. However geologic ages of these Cenozoic rock samples submitted to the present study are hardly to be decided, the samples are roughly devided into three groups of the geologic epock, namely,Pleistocene(Site Nos. 8 and 9),Pliocene(Site Nos. 1 , 7､10 and 11)and Miocene(Site Nos. 2,3,4and 12).0f course, these ages are dubious as mentioned above, and within the same group,the respective age is also out of the sequence.0n the other hand, the rock types are mainly andesites and few basaltics. Also liparite and tuff are seen (as shown in Table l appearing below).3)Remanent magnetizations; NRM and cleaned RM of the test specinlens were measured by means of an astatic magnetometer before and after the performance of AF demagnetization using a Rugby一ball shaped demagnetizer(Domen,1982).Few flake specimens chipped from respective rock sample thus measured-magnetic submitted to the thermo-magnetic (Js-T)analysis,for which an automatic thermo-magnetic balance was employed.4)The data about the paleomagnetic measurements thus obtained are shown in figures for the respective site as Fig. 2-1~Fig.2-12.
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