Geochemistry, Hydrothermal alteration and Ore mineralogy of Skarn Mineralization at Wethey-Pheshey area, Thabeikkyin Township, Mandalay Region, Myanmar

Toe Naing Oo; Lucas Donny Setijadji; I Wayan Warmada; Than Than Oo

doi:10.22146/jag.26961

Geochemistry, Hydrothermal alteration and Ore mineralogy of Skarn Mineralization at Wethey-Pheshey area, Thabeikkyin Township, Mandalay Region, Myanmar

https://doi.org/10.22146/jag.26961

Toe Naing Oo^(1*), Lucas Donny Setijadji⁽²⁾, I Wayan Warmada⁽³⁾, Than Than Oo⁽⁴⁾

(1) Department of Geology, Dagon University, Yangon, Myanmar
(2) Geological Engineering Department, Faculty of Engineering, Gadjah Mada University
(3) Geological Engineering Department, Faculty of Engineering, Gadjah Mada University
(4) Department of Geology, Dagon University, Yangon, Myanmar
(*) Corresponding Author

Abstract

Wethey-Pheshy area is located 80 km north of Mandalay at Thabeikkyin Township, Mandalay Region. X-ray Diffraction (XRD) Analysis and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) were applied in this study. Geochemical studies on the host rocks indicate that major and minor oxides compositions of metamorphicrocks show some degree of variation. CaO, MgO, FeO, TiO2 and P2O5 concentration of the metamorphic rock samples show a coherent negative correlation with SiO2 whereas Na2O is positively correlated with SiO2. The metamorphic rocks are strongly enriched in light rare earth elements (LREE) and relatively depleted in heavy rare earth element (HREE). The depleted Eu-nomalies in the chondrite-normalized REE diagrams indicate a plagioclase-depleted Eu crustal source or fractionation during magmatic differentiation. Intrusion of granitic rocks in the diopside marble caused the base metal ore mineralization and associated skarn alterations. Granite shows the sub-alkaline nature and peraluminous character. It is identified as I-type granite (magnetite series) developed in the volcanic arc setting. Hydrothermal alteration types associated with gold and skarn mineralization in the study area include calc-silicate alteration, propylitization, sericitization (argillitization) and hematization. Based on the nature and characteristics of host rocks, mineralization and alteration style and geochemical characteristics in the study area is identified as intrusion-related skarn mineralization. Common ore minerals include chalcopyrite, galena, sphalerite, pyrite, gold and Fe-oxides.

Keywords

Wethey-Pheshey area · Skarn · Mineralization · Hydrotermal alteration · Geochemistry · Myanmar.

Full Text:

PDF

References

Cox, K.G., Bell, J. D., Pankhurst, R.J. (1979) The interpretation of Igneous Rocks. Allen & Unwin. London.

Nakamura N. (1974) Determination of REE, Ba, Fe, Mg, Na and K in carbonaceous and oridinary chondrites. Geochim. Cosmochim. Acta, 38, 575775.

Pearce, J.A., Harris, N.B.W. and Tindle, A.G. (1984) Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. Journal of Petrology, 25. Part 4. 956-983.

Searle, D.L., and Haq B.T. (1964) The Mogok Belt of Burma and its relationships to the Himalayan Orogeny, in Proceeding of the 22nd International Geological Conference. Delhi, 11: 132-161.

Sun, S.S., McDonough, W.S. (1989) Chemical and isotopic systematic of oceanic basalts: implications for mantle composition and processes. In: Saunders A.D., Norry M.J (Eds.), Magmatism in the Ocean Basins. Geological Society of London, Special Publication, 313–345.

Swe, W. (1972) Strike-slip faulting in Central Belt of Burma. Paper read at the Fifth Burma Research Congress. Contributions to Burmese Geology. Vol.1, No.1, pp. 63-72.

Thein, M. L., Myint, O., Kyi, S., Win, H. N. (1990) “Geology and Stratigraphy of the Metamorphosed early Palaeozoic Rocks of the MogokThabeikkyin-Singu-Mandalay Areas”, Research paper Session II in Communication of Diamond Jubilee, p. 2-3.

Whalen, J.B., Currie, K. L., Chappell, B.W. (1987) A-type granites: Geochemical characteristics, discrimination and petrogenesis. Contrib. Mineral. Petrol., 95, 407-419.

Zaw, K., Sutherland, L., Yui, T.F., Meffre, S., Kyaw Thu (2014) Vanadium-rich ruby and sapphire within Mogok Gemﬁeld, Myanmar: implications for gem color and genesis. Mineralium Deposita, DOI: 10.1007/s00126-014-0545-0.

DOI: https://doi.org/10.22146/jag.26961