dc.contributor.author |
Dushyantha, NP |
|
dc.contributor.author |
Hemalal, PVA |
|
dc.contributor.author |
Jayawardena, CL |
|
dc.contributor.author |
Ratnayake, AS |
|
dc.contributor.author |
Ratnayake, NP |
|
dc.contributor.editor |
Abeysinghe, AMKB |
|
dc.contributor.editor |
Samaradivakara, GVI |
|
dc.date.accessioned |
2022-03-21T08:20:18Z |
|
dc.date.available |
2022-03-21T08:20:18Z |
|
dc.date.issued |
2018-08 |
|
dc.identifier.citation |
Dushyantha, N.P., Hemalal, P.V.A., Jayawardena, C.L., Ratnayake, A.S., Ratnayake, N.P. (2018). Geochemical approach of phosphate mineral exploration in lake sediments around Eppawala phosphate deposit, Sri Lanka [Abstract]. In A.M.K.B. Abeysinghe & G.V.I. Samaradivakara (Eds.), Proceedings of International Symposium on Earth Resources Management & Environment 2018 (pp. 11). Department of Earth Resources Engineering, University of Moratuwa. |
en_US |
dc.identifier.uri |
http://dl.lib.uom.lk/handle/123/17425 |
|
dc.description.abstract |
Mineral exploration is a stochastic process of finding and locating commercially
viable mineral resources. In this regard, lake sediment is an important material in
exploration as it contains three distinct types of minerals i.e. allogenic or detrital
minerals (minerals brought into the lake from outside of the lake), endogenic
minerals (minerals originated within the lake) and authigenic minerals (minerals
formed during the diagenetic alteration of sediments). Koon-wewa, Ihalahalmillawewa
and Kiralogama-wewa are three lakes connected with a man-made water
canal, namely Jaya-Ganga flowing across the Eppawala Phosphate Deposit (EPD).
Kiralogama-wewa is located downstream of the EPD whereas other two lakes are
located upstream. Thus, lake sediments in the downstream lake could be influenced
by the phosphate-bearing minerals derived from the EPD. The bulk chemical
analyses of surface lake sediments showed that average P2O5 concentrations were
0.80% and 0.45% in downstream and upstream, respectively. Further, in
downstream, P2O5 significantly and positively correlated with AI2O3, CaO, Fe203,
K2O and MnO whereas no such correlations were observed in upstream sediments.
Presence of calcium-iron-aluminum phosphate minerals such as fluorapatite,
crandallite, millisite and strengite in downstream sediments, revealed via
mineralogical analyses, delineated the above correlations. Moreover, high Chemical
Index of Alteration (CIA) values were observed in the downstream sediments which
indicate intense chemical weathering conditions in the source area. It is justified by
the presence of weathering products of the EPD such as crandallite and millisite in
the downstream sediments. Grain size analyses displayed a dominant silt fraction in
both upstream and downstream areas. Textural analyses in downstream revealed
the relative proximity of the source and nature of the material deposition through
solid suspension. Presence of fluorapatite (detrital mineral) in downstream is
corrobarated the conclusion in textural analyses. Four representative core samples
were obtained from both the upstream and downstream lakes. In upstream core
samples, P2O5 concentrations varied from 0.03% to 1.81% whereas P2O5
concentrations in downstream core samples varied f r om 0.26% to 2.22%. Continuous
sediment supply via Jaya-Ganga can also improve the fertilizing capacity of
downstream lake sediments, eventually; becoming a commercially viable phosphate
mineral resource. |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
Department of Earth Resources Engineering |
en_US |
dc.subject |
Eppawala phosphate deposit |
en_US |
dc.subject |
Lake sediments |
en_US |
dc.subject |
Phosphates |
en_US |
dc.subject |
Weathering |
en_US |
dc.title |
Geochemical approach of phosphate mineral exploration in lake sediments around Eppawala phosphate deposit, Sri Lanka |
en_US |
dc.type |
Conference-Abstract |
en_US |
dc.identifier.faculty |
Engineering |
en_US |
dc.identifier.department |
Department of Earth Resources Engineering |
en_US |
dc.identifier.year |
2018 |
en_US |
dc.identifier.conference |
International Symposium on Earth Resources Management & Environment 2018 |
en_US |
dc.identifier.place |
Thalawathugoda |
en_US |
dc.identifier.pgnos |
p. 11 |
en_US |
dc.identifier.proceeding |
Proceedings of International Symposium on Earth Resources Management & Environment 2018 |
en_US |
dc.identifier.email |
nimila.dush@gmail.com |
en_US |
dc.identifier.email |
nalin@uom.lk |
en_US |
dc.identifier.email |
chulanthaj@uom.lk |
en_US |
dc.identifier.email |
hemalal@uom.lk |
en_US |