2024-03-28T08:46:38Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/367152022-11-17T02:08:08Zhdl_2115_34896hdl_2115_34816hdl_2115_116Phase Relations in the Chromium-Poor Part of the System Diopside-Anorthite-Forsterite-MgCr2O4 in Air at 1 atmOnuma, Kosuke450The effect of chromium on the silicate system was studied at 1 atm by adding MgCr2O4 to the join diopside-anorthite-forsterite which is a thermal divide in the system CaO-MgO-Al2O3-SiO2. When a small amount of MgCr2O4 (0.2 - 0.5 wt%) is added to the join, the liquidus surface for spinel expands at the expense of anorthite. Thus, the assemblage diopside + forsterite + anorthite + liquid at a ternary invariant point becomes unstable and the assemblages of diopside + anorthite + spinel + liquid and diopside + forsterite + spinel + liquids appear on the liquidus surface. The points at which these assemblages are present are not "invariant" point but "piercing" point, indicating that the join diopside-anorthite-forsterite with a small amount of chromium is not thermal divide, and that the residual liquid in the crystallization can move through the join diopside-anorthite-forsterite.北海道大学Departmental Bulletin Paperapplication/pdfhttp://hdl.handle.net/2115/36715https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/36715/1/20_2-3_p171-183.pdf0018-3474北海道大学理学部紀要202-31711831983-02engpublisher