Tephra stratigraphy, facies and grain compositions of the Shinanomachi Loam Formation distributed around Lake Nojiri-ko

The Shinanomachi Loam Formation is composed of tephric loess, volcanic ashes, pumice and scoria lapllius, is overlain by the Kamiyama Loam Formation and Nojiri Loam Formation. At two well exposures at approximately 4 km south and 5 km north-east of Lake Nojiri-ko, we described litho-facies and grain compositions. Based on these litho-facies and grain compositions, and stratigraphic relationship, we are revealed that some tephra bed in the Shinanomachi Loam Formation is correlated to “Iz-KT a”, “Iz-KT c” and “In-Ny” wide-spread tephras.Article野尻湖ナウマンゾウ博物館研究報告. 27: 15-26(2019)journal articl

Grain composition and sediment chemistry of the Kannoki Silt Member and the Umibata Sand and Silt Member at the 22nd Nojiri-ko Excavation site, central Japan.

We clarified the grain composition and sediments chemistry of the Kannoki Silt Member and the Umibata Sand and Silt Member at Lake Nojiri-ko, central Japan. The grain composition of 2 phi to 3 phi composed mainly of plagioclase, lithic fragments, orthopyroxene, clinopyroxene and hornblende. This result agree with our previous studies. Major and trace element compositions of sediments finner than pebble size were measured using X-ray fluorescence analysis. The result of major element composition show basaltic andesite to andesite compotions. We are recognized strtigraphic variations of the Enrichment Factor of the MgO, Fe2O3 and TiO2, and the variations correspond to mafic minerals contents.Article野尻湖ナウマンゾウ博物館研究報告. 28: 25-33(2020)journal articl