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ID 21169
Eprint ID
21169
FullText URL
Title Alternative
Ammonium content of Archean rocks of the Superior Province
Author
Honma, Hiroji
Schwarcz Henry P.
Abstract
Ammonium contents were determined for clastic sediments and associated volcanic rocks of the Kirkland Lake area, Abitibi greenstone- granite belt and metamorphic, migmatitic and granitic rocks of the Ear Falls-Dryden area, English River gneiss-granite belt. The NH(4) centents of Archean volcanic rocks (2700~2710m.y.) are very low (0~6 ppm) and immature argillites have also low contents of NH(4) (27~43ppm). On the other hand, a black shale from the Timiskaming Group (2100m.y.) are rich in graphite and pyrite and contain much NH4 (130ppm), providing a firm evidence of relatively abundant presence of an Archean biota compared with a sparcity of morphological record of Archean fossils. The NH(4) content of the rock mentioned above is about a third of those of the upper Proterozoic sediments and it remains to be established whether it reflects the abrupt break in the evolution of life near the Archean-Proterozoic boundary or not. A considerable amount of NH(4) is inherited by highly metamorphic pelitic gneisses and there may be a possibility for indirect prospection of early life by a study of NH(4) in highly metamorphic rocks of the early Archean. It was also found that the gneissic granitoid has much higher content of NH(4) than the post· kinematic massive granitoid.
Note
原著論文 (Original Papers)
Published Date
1979-09-25
Publication Title
岡山大学温泉研究所報告
Publication Title Alternative
Papers of the Institute for Thermal Spring Research, Okayama University
Volume
volume49
Publisher
岡山大学温泉研究所
Publisher Alternative
Institute for Thermal Spring Research, Okayama University
Start Page
7
End Page
13
ISSN
0369-7142
NCID
AN00032853
Content Type
Departmental Bulletin Paper
language
日本語
OAI-PMH Set
岡山大学
File Version
publisher
Refereed
False
Sort Key
4
Eprints Journal Name
mmc