REE Comparison Between Muncung Granite Samples and their Weathering Products, Lingga Regency, Riau Islands

Abstract

-The increasing demand for Rare Earth Elements (REE) is related to the continous development of technology, and these elements are used in modern equipments. REE can occur in igneous and sedimentary rocks in significant amounts as primary deposits, whereas the secondary REE deposit can be produced by intensive lateritic weathering of bedrocks under the tropical or subtropical climate. Lateritic process can increase REE concentration from sub-economic levels in host rocks to be more valuable. Muncung Granite is located in a tropical area of Lingga Regency, Riau Islands Province. REE occurs in the Muncung Granite and in weathered layers (saprolite, laterite, and soil). ICP-MS was applied to measure the REE content in all samples of this study. The average REE content of the Muncung Granite is 265 ppm with Eu anomaly in REE's spider diagrams. Lateritization process has increased REE content by more than four times compared to that in the Muncung Granite. Ce and Eu anomalies in weathered layers can be associated with weathering process and initial REE contents in the host rock. Ce anomaly in a laterite layer is found to have a negative correlation to REE total enrichment. The REE level in the Muncung Granite is higher than the content in the soil and saprolite layers, but lower than that in the laterite.

Heavy Metals Content and Pollution in Tin Tailings from Singkep Island, Riau, Indonesia

“…Acid destruction was applied using hydrofluoric acid, perchloric acid, and nitric acid. ICP-MS was run adapting the recommended parameters of the previous study about weathered granite (Irzon et al 2016). AGV2 and GBW 07113 were the two certified reference materials (CRM) to verify the measurement results.…”

“…The climate of Singkep Island is tropical with dry and rainy seasons. The average temperature in the part of Lingga Regency is 28°C and the range of yearly rainfall is 1,000 -3,000 mm (Irzon et al 2016).…”

“…Previous studies showed that the disposed of tailings caused health and environmental problems that are hazardous to the local resident (Alshaebi et al 2009;Ashraf et al 2012Ashraf et al , 2011Asmarhansyah et al 2017;Domingo and David 2014;Nurtjahya et al 2017;Selinus 2004;Wapwera et al 2015;Zulfahmi et al 2012). Besides, as tin mineralization correlated with S-type granite which also contains REE, the tailing is proved to contain a valuable number of REE (Irzon et al 2016).…”

Thorium and Total REE Correlation in Stream Sediment Samples from Lingga Regency

“…Lingga Regency is located in Riau Islands Province with Daik as the capital. Tin was produced massively in Lingga Regency for more than four decades and was one of the three main resource locations in Indonesia besides Bangka and Belitung [8,9]. The tin exploitation was centered in Dabo, Singkep Island.…”

“…Although REE comprise significant amounts of many minerals, almost all production came from less than 10 minerals, Eksplorium p-ISSN 0854-1418 Volume 39 No. 1, Mei 2018: [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] e-ISSN 2503-426X 3 such as apatite, bastnasite, monazite, xenotime, gadolinite, and cerianite. Those minerals are described with different elemental formulas, which are mobilized by weathering from adjacent watersheds into streambeds and affect the chemical content.…”