Role of uranium in controlling radiogenic heat production based on gamma ray spectrometry and thermal remote sensing data, southwestern Sinai, Egypt

Structure of the Carboniferous Altenberg-Teplice Caldera (Eastern part of the Krušné hory/Erzgebirge Mts.) revealed by combined airborne and ground gamma-ray spectrometry

“…Among the natural radioactive elements, the relatively immobile Th seems to be the best lithological indicator (e.g., Breiter et al 1998 in the Moldanubian Pluton;Leichmann et al 2016 in the Třebíč durbachite Pluton). The use of U in petrological studies is limited because of its solubility and mobility (e.g., Attia and Wahid 2016;Rihs et al 2016;Weihermann et al 2016;Kanzari et al 2017). The distribution of potassium can contribute to lithological studies but it might also indicate rock alterations accompanying ore-bearing processes (Gnojek and Přichystal 1985).…”

“…The airborne data were locally supported by in-situ measurements on bedrock outcrops. The concentrations of natural radioactive elements were acquired using a portable gamma-ray spectrometer GRM-256 (GF Instru-Concentrations of mobile U tend to be modified by post-magmatic processes (e.g., Attia and Wahid 2016;Rihs et al 2016;Weihermann et al 2016;Kanzari et al 2017), and do not reflect the petrology so directly as K and Th. For that reason, we discuss concentrations of K ( Fig.…”

Gamma-ray spectrometry in the field: Radioactive heat production in the Central Slovakian Volcanic Zone

“…The impression created by the Chernyshev et al (2013) paper, of uniform composition of both the dioritic and granodioritic parts of the pluton, would therefore appear to be an artefact of the small number of samples that they analysed. Regarding the effects of the different radionuclides, one expects uranium to be the most significant contributor to heat production (e.g., Birch, 1954;McCay et al, 2014;Attia and Wahid, 2016). However, using the aforementioned 'best estimate' values for composition, at the majority of our sites, 34 out of 62 or ~55%, thorium made the largest contribution to heat production (see the online supplement).…”

“…Furthermore, although one expects uranium content to increase inward from the margins of a granodioritic pluton, reflecting its zoned composition (e.g., Rybach, 1976; see also below), some sites well inside the pluton have low uranium concentrations (Table 3). We infer the cause of this to be the high solubility that uranium can attain under environmental conditions (e.g., Casas et al, 1998;Elless and Lee, 1998;Gorman-Lewis et al, 2008;Attia and Wahid, 2016) combined with the hydrothermally altered state of many samples that (by breaking down the crystal structure of the mineral grains in which the uranium would have been concentrated in the original rock) is likely to facilitate uranium release. On this basis, the measurements with the highest uranium concentrations and heat production values are likely to provide the best estimates for rocks in the Štiavnica pluton that have not been affected by hydrothermal alteration or surface environmental conditions.…”

“…In addition, this scintillator material was relatively insensitive, so the detectors had to be made rather large to avoid long measurement times. One, nonetheless, occasionally sees publications reporting continued use of this older generation of equipment (e.g., Attia and Wahid, 2016).…”