ISERME - 2020

Permanent URI for this collectionhttp://192.248.9.226/handle/123/16969

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Browsing ISERME - 2020 by Author "Dharmaratne, PGR"

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    item: Conference-Abstract
    An investigation of industrial mineral mining methods in Sri Lanka
    (Department of Earth Resources Engineering, University of Moratuwa, 2020-12) Thanujan, T; Subasinghe, MAIIJ; Vettinathan, S; Dharmaratne, PGR; Hemalal, PVA; Chaminda, SP; Jayawardena, CL; Dissanayake, DMDOK; Dassanayake, ABN
    Sri Lanka is endowed with a rich base of industrial minerals despite its small land area. Traditional and modernized mining methods are employed to mine graphite, limestone, beach mineral sand (ilmenite, rutile, zircon and garnet), apatite, calcite, dolomite, quartz, feldspar, clay, kaolin, silica sand, mica and rock aggregate. Notably, some deposits have not been optimally exploited to their potential. Moreover, Sri Lanka does not have comprehensive information and documentation in the mining context. The mining method is selected on the basis of respective geology of the deposit, hardness of the ore and rock, depth, thickness and other geological aspects etc. The extraction of narrow steeply dipping vein deposits and deposits at great depth are significantly challenging and need specified selective mining techniques. In the study, currently practiced mining technologies, Cutand- Fill mining at Bogala, Open-stopping at Kahatagaha mines, open cast mining at Aruwakkalu Limestone quarry and mineral sand mining at Pulmoddai were investigated. The investigation was carried out through interviews and field visits. Site characteristics of each mine were tabulated, and the mining procedures were discussed. Mining methods employed at Kahatagaha and Pulmoddai were traditional while Bogala and Aruwakkalu utilize more systematic technologies. It is recommended to investigate and conduct indepth analysis in the second phase of the study for technological improvements.
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    item: Conference-Abstract
    REE Potential in carbonatite deposits: a case study of Eppawala carbonatite
    (Department of Earth Resources Engineering, University of Moratuwa, 2020-12) Batapola, NM; Dushyantha, NP; Premasiri, HMR; Abeysinghe, AMKB; Rohitha, LPS; Ratnayake, NP; Dissanayake, DMDOK; Ilankoon, IMSK; Dharmaratne, PGR; Dissanayake, DMDOK; Dassanayake, ABN
    Rare earth elements (REEs) are currently the most strategic elements in the world due to their significance in the diversified technological applications. Currently, a total of 478 million tonnes of REE resources is disseminated across the world, which is dominated by the carbonatite deposits. The most common REE-bearing minerals found in carbonatites are bastnaesite, apatite, monazite, allanite and parisite. In this regard, the Eppawala carbonatite in Sri Lanka could be considered as a potential REE resource. The Eppawala carbonatite occurs in high-grade meta-sedimentary and igneous rocks of the Precambrian Wanni Complex as massive intrusions. In the Eppawala carbonatite, bed rock is mainly composed of calcite (~90%), dolomite (5-9%) and magnesite (accessory carbonate mineral), whereas chloro-fluor-hydroxyapatite, fluorapatite and carbonate-fluorapatite are present in a secondarily developed phosphate-rich regolith. The Eppawala carbonatite is enriched of REEs (~291-1962 ppm) with higher concentrations of LREEs. However, despite these evidences, only a few REE prospecting studies have been carried out in the Eppawala carbonatite. Therefore, detailed REE prospecting studies are recommended to discover the full potential of this prospect, followed by development of suitable REE extraction processes.