Library Open Repository

Geochemistry and tectonic setting of the Central Loei volcanic rocks, Pak Chom area, Loei, northeastern Thailand

Downloads

Downloads per month over past year

Panjasawatwong, Y and Zaw, K and Chantarameea, S and Limtrakun, P and Pirarai, K (2006) Geochemistry and tectonic setting of the Central Loei volcanic rocks, Pak Chom area, Loei, northeastern Thailand. Journal of Asian Earth Sciences, 26. pp. 77-90.

[img] PDF
Panjasawatwong,_Zaw_et_al_2006.pdf | Request a copy
Full text restricted
Available under University of Tasmania Standard License.

Abstract

The Central Loei volcanic rocks, as evidenced by those in the Pak Chom area, were formed in the Late Devonian-Early Carboniferous and can be separated into three magmatic groups: transitional tholeiitic basalt, tholeiitic microgabbro and calc-alkalic basalt/andesite on the basis of immobile-element contents and ratios of least altered samples. All the tholeiitic microgabbro possibly occurred as dikes. Chemically, the transitional tholeittic basalt and tholeiitic microgabbro have higher abundances of TiO2, Ni and Cr relative to the calc-alkalic basalt/andesite at similar values for FeO*/MgO; they also contain higher Ti/Zr but lower Zr/Nb. The transitional tholeiitic basalt has higher concentrations of P2O5 and Nb relative to the tholeiitic microgabbro at similar levels of FeO*/MgO, and also has higher ratios of Nb/Y and Ti/V, but lower values for Ti/Zr and Zr/Nb. In terms of chondrite normalized REE and N-MORB normalized patterns, the transitional tholeiitic basalt, tholeiitic basalt and calc-alkalic basalt/andesite are analogous to those from North Atlantic, Southwest Indian Ridge and New Britain Arc. On this basis, the Central Loei volcanic rocks are comprised of MORBs and oceanic island-arc lavas. These arc lavas may have erupted on an oceanic basement in the same ocean basin as those in the Chiang Rai-Chiang Mai volcanic belt.

Item Type: Article
Keywords: REE, Island arc, MORB, SE Asia, Phetchabun
Journal or Publication Title: Journal of Asian Earth Sciences
Page Range: pp. 77-90
Identification Number - DOI: 10.1016/j.jseaes.2004.09.008
Date Deposited: 05 Jul 2007
Last Modified: 18 Nov 2014 03:18
URI: http://eprints.utas.edu.au/id/eprint/1310
Item Statistics: View statistics for this item

Repository Staff Only (login required)

Item Control Page Item Control Page