*W.L.A.C.I. Weedagama ^1,2, N.W.B. Balasooriya², Atula Senaratne², Bhathiya Athurupana², Rohana Chandrajith², Nadeesha H. Koralegedara² (1.Post Graduate Institute of Science, University of Peradeniya, Peradeniya, Sri lanka, 2.Department of Geology, University of Perdeniya, Peradeniya, Sri Lanka)