SHRIMP U-Pb dating of detrital zircons in metamorphic rocks from northern Kyushu, western Japan

DOI Web Site 15 Citations 44 References Open Access

Bibliographic Information

Other Title
  • SHRIMP U-Pb dating of detrital zircons in metamorphic rocks from the northern Kyushu, western Japan
  • SHRIMP U-Pb dating of detrital zircons in metamorphic rocks from northern Kyuhsu, western Japan
Published
2003
DOI
  • 10.2465/jmps.98.181
Publisher
Japan Association of Mineralogical Sciences

Search this article

Description

Radiometric ages of detrital zircons in psammitic schists from the Nagasaki, Kurume, Konoha and Kiyama areas, northern Kyushu, were obtained from 238U/206Pb ratio and isotopic compositions of Pb using a Sensitive High Resolution Ion Microprobe (SHRIMP II). Zircons from the Nagasaki, Kurume and Konoha areas show bimodal age distribution with peaks at ca. 1900 Ma and 250 Ma. It is suggested from this study that the older zircons were derived from Proterozoic landmass and the Korean Peninsula. Zircons from the Kiyama metamorphic rock show a different pattern with ages concentrated at 380-590 Ma. Such zircons are rare in rock samples from the Nagasaki, Kurume and Konoha areas, indicating that Kiyama rocks had a different origin than those from the other three areas. <BR>The youngest zircons from the Kiyama, Nagasaki, Kurume and Konoha areas show ages of 382±28 Ma, 238±13 Ma, 249±13 Ma, and 175±4 Ma, respectively. These data mark the upper age limit of their deposition. Since a continuous igneous activity occurred during the period from 300 to 170 Ma in Far East Asia, and the metamorphic age has been close to the zircon age of each area, these youngest ages for the Nagasaki, Kurume and Konoha areas are considered nearly contemporary to the depositional ages. An evaluation of the nature of metamorphism and available ages suggest the possibility that the Nagasaki metamorphic rocks as well as the schist from the Kurume area belong to the Suo zone of the Sangun belt, whereas the metamorphic rocks in the Konoha area may belong to the Ryoke belt or Suo zone of the Sangun belt.

Journal

Citations (15)*help

See more

References(44)*help

See more

Details 詳細情報について

Report a problem

Back to top