@phdthesis{oai:nagoya.repo.nii.ac.jp:00004860,
 author = {Sugitani, Kenichiro and 杉谷, 健一郎},
 month = {Feb},
 note = {Geochemical and mineralogical characteristics of Archean sedimentary rocks such as cherts, banded iron-formations (BIFs), shales and sandstones collected from the pilbara Block, Western Australia were studied. Lithologic features of various types of chert occurring within the Pilbara Supergroup are closely related to their chemical compositions. Red and brown bands of banded cherts generally show higher Fe2O3(total iron as Fe2O3) than do other cherts, whereas grey, greenish-grey and pale yellowish-grey cherts are characteristic of relatively higher concectrations of Al and Ti. White cherts are generally composed almost exclusively of SiO2. Geochemical characteristics of the cherts suggest that they were precipitated from hydrothermal solutions. Evidence for the hydrothermal origin includes (1) low MnO/Fe2O3 values, (2) low contents of heavy metals, (3) positive Eu-anomalies, (4) low Co/Zn and Ni/Zn values and (5) high concentrations of Mn and Fe in carbonates. Positive correlations between Fe and heavy metals such as Ni and Zn imply the intermittent precipitation of Fe-oxides (hydroxides) along with these heavy metals in the ancient ocesn. Cherts, except for grey, greenish-grey and pale yellowish-grey cherts, are highly depleted in detrital materials. This may have been caused by rapid precipitation of hydrothermally-derived Fe and Si. The Archean ”Pilbara Ocean“ is believed to have been enriched in Fe and Si derived from hydrothermal activity., 名古屋大学博士学位論文 学位の種類:理学博士 (課程) 学位授与年月日:平成4年2月6日},
 school = {名古屋大学, Nagoya University},
 title = {Geochemical Characteristic of Archean Cherts and Other Sedimentary Rocks in the Pilbara Block,Western Australia: Evidence for the Archean Sea-Water Enrichedin Hydrothermally-Derived Iron and Silica},
 year = {1992}
}