IntroductionAll varieties of building materials, including various naturally occurring as well as artificial materials, have varying concentrations of Ra, Th, and K and can cause direct radiation exposure to human beings. Granite, as a market term, includes a wide variety of rock types including plutonic, volcanic, and metamorphic rocks. Granite's durability and appearance make it a popular building material in dwellings. These rocks can contain various amounts of minerals with high Ra, Th, and K concentrations such as zircon, monazite, xenotime, allanite, epidote, or K-feldspars.According to the European Commission (1999), radioactive doses should comply with the ALARA ("as low as reasonably achievable") radioprotection principle. The average annual effective equivalent should be limited to 1.6 mSv. Materials such as granites, potentially containing high concentrations of natural radionuclides, should be studied in order to control the exposure levels for human beings. The limit of 1.6 mSv per year is widely accepted by many international organisations such as the International Commission on Radiological Protection (ICRP), the World Health Organization (WHO), and the European Commission.Natural radionuclides increase both the external (γ-rays) and internal (α-rays) radiation to human beings. 238 U, 232 Th, and 40 K are the main contributors of γ-rays, while α-rays are principally emitted by radon, a decay product of 238 U radioactive series. The Rn isotopes are responsible for roughly half of the radioactive dose exposure from natural sources. Moreover, Rn isotopes are considered as an important cause of lung cancer (UNSCEAR, 2000; WHO, 2009). Many investigations on the radioactivity levels of granitic rocks, used or potentially used as decorative and building materials, can be found in the recent literature

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This paper presents the preliminary results regarding the lithostratigraphy, petrography and petrology of James Ross Island Volcanic Group dominating the Lachman Crags and Cape Lachman lava-fed deltas in the Ulu Peninsula, James Ross Island north-eastern Antarctic Peninsula. Studied lava-fed deltas were produced via Late Miocene to Pleistocene sub-marine and sub-glacial volcanism and made up four main lithofacies: a- bottomset pillow lavas, peperites and associated volcanoclastic/siliciclastic deposits; b- foreset-bedded hyaloclastite breccias; c- intrusions (feeder dykes, sills, and plugs) and d- topset subaerial lavas. Collectively these lithofacies record the transition from an effusive subaqueous to an effusive subaerial eruption environment. All lava samples and dykes from bottomset, foreset and topset lava-fed delta associations are olivine-phyric alkali basalts and are mineralogically and geochemically homogeneous. These eruptive products display significant enrichments in alkali contents and have ocean island basalt (OIB)-type, intra-plate geochemical signatures characterized by enrichments in all highly to moderately incompatible trace elements relative to basaltic rocks from ocean ridge settings. Volcanic products from a number of different eruptive periods display limited variations in major and trace element relative abundances, indicating derivation from a relatively homogeneous mantle source. The results of quantitative modelling of geochemical data is consistent with the view that the primary melts from which these mafic alkaline rocks were originated are the products of relatively small degrees (~3-7%) of partial melting of a volatile-bearing, metasomatized mantle source. The magmatism is likely the result of extension-driven mantle upwelling.

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The natural radioactivity of the Western Anatolian plutonic bodies (Turkey), as well as the assessment of any potential health hazard due to their usage as decorative building materials is studied. Seventy samples from Western Anatolian plutonic bodies, including various rock-types from quartz