Jadeite-bearing meta-basalt occur within a greenstone complex at the southern margin of the Mikabu greenstones in the Shimonita area, northern Kanto Mountains, Central Japan. The greenstone complex shows a block-in-matrix structure consisting of small, sporadically occurring greenstone blocks (jadeite-bearing meta-basaltic lavas, jadeite-free pargasite rocks, and jadeite-free garnet-epidote rocks) embedded within a matrix of actinolite rocks. The complex has been interpreted as a tectonic mélange composed of allochthonous metamorphic blocks within the Mikabu greenstones. However, both the greenstone blocks and actinolite rocks preserve original igneous or pyroclastic textures without the deformation structures commonly seen in tectonic mélanges. The concentrations of high field strength (HFS) elements within the jadeite-bearing lavas indicate that these rocks are alkali basalts derived from oceanic island basalt (OIB). The composition of these lavas is similar to that of OIB blocks in the Mikabu greenstones in Shikoku, western Japan. The whole-rock chemical composition of the lavas reveals higher Na₂O concentrations (max. 10.1 wt%) than in unmetamorphosed Hawaiian OIB alkali basalts. The actinolite rocks of the matrix show a pyroclastic texture and contain relic Ca-pyroxenes. The concentrations of HFS elements and pyroxene chemistry of the actinolite rocks indicate an origin from tholeiitic MORB, similar in composition to typical Mikabu greenstones in the Kanto Mountains and Shikoku. These observations strongly suggest that the greenstone complex is not a tectonic mélange comprising allochthonous metamorphic rocks within a matrix of Mikabu greenstones, but that the entire complex consists of Mikabu greenstones. Therefore, the complex was subjected to Sanbagawa metamorphism after a Na-enrichment event; jadeite grew in Na-rich blocks during the metamorphism.

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  A portable CCD spectrometer was applied for the measurement of photoluminescence (PL) spectra of alkali feldspars. A calibration was carried out for the spectral sensibility of the system. PL spectra with different patterns were measured for the red and white PL of zoned alkali feldspars from the Tanakami granite pegmatites, Shiga Pref. The PL spectra of alkali feldspars principally consist of an intense emission band in red region and a weak emission band in blue-green region.

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  Information collected from geological newsmagazines in the latter of 2010 is reviewed. First topic is redevelopment of Afghanistan such as mining and management of water. Second topic is overview of resources of REE to assessing security of supply in USA. Third topic is current geoscience maps, i.e., geological mapping in response to societal needs and newly a released magnetic anomaly map of Australia.

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