Signature of Potassium Enrichment in Granite of the Chitrial Area, Nalgonda District, Andhra Pradesh: Inferences Using its U, Th, K2O, Na2O, Rb, Ba and Sr Contents

Abstract

A medium tonnage unconformity proximal uranium deposit has been established at Chitrial by the Atomic Minerals Directorate in the Srisailam sub-basin. In this type of deposits, the association of uranium with potassic alteration (illitization) is well-documented. The present study is directed towards understanding such an association in the Chitrial area for which the uranium mineralized borehole core samples were collected and analyzed. It is observed that the average concentrations of K2O, Na2O, Rb, Ba and Sr in the granite of the Chitrial area are 5.35%, 1.78%, 252 ppm, 564 ppm and 52 ppm, respectively, and they show average critical elemental ratios of K/Rb, Ba/Rb and Rb/Sr as 191, 2.37 and 7.13, respectively. The granites show low K/Rb, low Rb/Ba and high Rb/Sr ratios compared to that of the average crust indicating its derivation from crustal source. The samples have higher values of uranium (av. 53 ppm), thorium (av. 66 ppm) and lead (av. 41 ppm). The U/Th ratio in the granite varies from 0.07 to 20.86 with an average of 1.68. They also exhibit high K2O/Na2O ratio typical of post-Archaean granite and very high values suggest the possibility of later potassium enrichment.

Radon and thoron levels in the dwellings of Buddonithanda: a village in the environs of proposed uranium mining site, Nalgonda district, Telangana state, India

“…2 Department of Physics, Chaitanya Bharathi Institute of Technology, Hyderabad 500 075, India. * email: marrisr@gmail.com Atomic Minerals Directorate for Exploration and Research (AMDER), Hyderabad, has conducted several geological studies in Chitrial area of Nalgonda district and established that it is one of the prospecting potential areas for uranium exploration 9,10 . The mining activity possibly enhances the environmental nuclear radiation levels in the adjoining areas.…”

An ensialic volcanic arc along the northwestern edge of Palaeotethys—Insights from the Mid‐Triassic volcano‐sedimentary succession of Ivanščica Mt. (northwestern Croatia)

“…A range of K concentrations in analyzed tuffs reflects either a variable modal abundance of K‐feldspar, which is one of the basic products of volcanic activity (Lawrence, Drever, Anderson, & Brueckner, ), or higher proportion of micaceous phases. Alternatively, it can also partly results from late alteration processes and metasomatism, which usually leads to chemically distinct enrichment that is visually very subtle and therefore easily overlooked (Chapin & Lindley, ; Rajaraman, Nagendra Babu, Chavan, Achar, & Ramesh Babu, ). The enrichment in Na 2 O documented in samples ce‐11 and ce‐18 (>2.54 wt %) reflects higher modal contents of plagioclase (Figure c).…”

Comparison of fundamental physical properties of the model cells (protocells) and the living cells reveals the need in protophysiology

“…The ratio of K/Na in potassium-rich granites usually reaches 1 and rarely exceeds this value (Whitney 1988). However, in India recently were found granites with K 2 O/Na 2 O ratios ranging from 1.1 to 69.8 (Rajaraman et al 2013). In the modern ocean water and in the Archean era, the ratio was 0.02 (Pinti 2005).…”