Low-grade metamorphism and K-Ar ages of several accetionary complexes in Southwest Japan

本研究已完成课题三年，并按计划取得了一定的成果。本课题的主要内容如下：1. K.Chijiwa和Y.Nishimura研究了用Leitz MPV - Compact 2测量煤和泥质变质岩中含碳物质的电导率的方法，并建立了适当的测量方法。K. Chijiwa在1996年日本煤炭石油应用学会会议上报告了部分结果。Nishimura在日本西南部对几个增生杂岩进行了地质调查，测量了大量<002>碳质物质的d_2数据和重结晶多晶白云母的K-Ar年龄。一个来自Kiyama地区的结果在Jour印刷。日本地质学会（1995年）和Ikura地区的地质构造和变质作用（1996年）。一篇题为“三滚带的大地构造分区和面积范围”的论文发表在J.Metamorphic.Geol.（1998年）。中琉球弧的结果将被更全面地检查，并在不久的将来发表。T.Imaoka和Y.Nishimura在日本地质学会会议（1996年）上报告了Susa地区的结果，并将其发表在《石油经济地质学报》上。（1997年）。对分布于中琉球岛弧的多个小型花岗岩体进行了地质和岩石学调查，测定了10个黑云母和角闪石的K-Ar年龄。还将对此进行更全面的审查，并在不久的将来发表。Itaya与Y.Nishimura和T. Imaoka合作测量了大量的K-Ar数据。在《岛弧》（1996年）等杂志上发表论文《基于生物地层学和K-Ar年代学的美浓-丹波带西部侏罗纪增生杂岩的幕式增生和变质作用》。Y.Nishimura和T.Itaya在新西兰的一些增生杂岩中获得了极好的和完整的数据。这项研究现在就开始写，不久就会发表。

This study has expired the term of our project for three years, and gotten much results according to plan. Abstracts of our project are as follows :1. K.Chijiwa and Y.Nishimura have examined a method of reflactance measurment of coals and carbonaceous material from pelitic metamorphic rocks using a Leitz MPV - Compact 2, and established the proper measures. A part of the results was reported at the meeting of Soc. Appl.Coal Petrol.Japan (1996) by K.Chijiwa.2. Y.Nishimura has geologically surveyed several accretionary complexes in Southwest Japan, and measured a lot of d_<002> data of carbonaceous material and K-Ar ages of recrystallized phengitic mica. A result from the Kiyama area was printted in Jour. Geol.Soc.Japan (1995), and that from the Ikura area in Tectonics and Metamorphism (1996), respectively. A paper entitled "Geotectonic subdivision and areal extent of the Sangun belt" was appeared in J.Metamorphic.Geol.(1998). Results from the Middle Ryukyu Arc will be examined more fully, and published in near furture.3. T.Imaoka and Y.Nishimura reported a result from the Susa area at the meeting of Geol. Soc.Japan (1996), and printed it in Jour.Min.Petrol.Econ.Geol.(1997). They also have geologically and petrologically surveyed many small granitic bodies scattered in the Middle Ryukyu Arc, and measured 10 K-Ar ages of biotite and hornblend. This will be also examined more fully, and published in near furture.4. T.Itaya has measured a lot of K-Ar data in cooperation with Y.Nishimura and T.Imaoka. He published a papers entitled "Episodic accretion and metamorphism of Jurassic accretionary complexes based on biostratigraphy and K-Ar geochronology in the western part of the Mino-Tanba Belt" in The Island Arc (1996) and so on.5. Y.Nishimura and T.Itaya have obtained excellent and full data from some accretionary complexes in New Zealand. This study is going to write now, and will be published before long.