Geochemical characteristics of the oceanic islandtype volcanic rocks in the Chiang Mai zone,northern Thailand  

作　　者：SHEN Shangyue FENG Qinglai ZHANG Zhibin CHONGPAN Chonglakmani 

机构地区：[1]China University ofGeosciences, Wuhan 430074, China [2]Institute of Regional Geology, Yunnan Bureau of Geology and Mineral Resources, Yuxi 653100, China [3]Suranaree University of Technology, Thailand

出　　处：《Chinese Journal Of Geochemistry》2009年第3期258-263,共6页中国地球化学学报

基　　金：granted by the National Natural Science Foundation of China (Grant Nos. 40372105 and 40772143)

摘　　要：The oceanic island volcanic rocks in the Chiang Mai zone, northern Thailand, are usually covered by Lower Carboniferous and Upper Permian shallow-water carbonate rocks, with the Hawaii rocks and potash trachybasalt being the main rock types. The alkaline series is dominant with sub-alkaline series occurring in few cases. The geochemical characteristics are described as follows: the major chemical compositions are characterized by high TiO2, high P2O5 and medium K2O; the rare-earth elements are characterized by right-inclined strong LREE-enrichment patterns; the trace element patterns are of the upward-bulging K-Ti enrichment type; multi-component plots falling within the fields of oceanic island basalts and alkali basalts, belonging to the oceanic island-type volcanic rocks, which are similar to the equivalents in Deqin and Gengma (the Changning-Menglian zone) of Yunnan Province, China.The oceanic island volcanic rocks in the Chiang Mai zone, northern Thailand, are usually covered by Lower Carboniferous and Upper Permian shallow-water carbonate rocks, with the Hawaii rocks and potash trachybasalt being the main rock types. The alkaline series is dominant with sub-alkaline series occurring in few cases. The geochemical characteristics are described as follows： the major chemical compositions are characterized by high TiO2, high P2O5 and medium K2O; the rare-earth elements are characterized by right-inclined strong LREE-enrichment patterns; the trace element patterns are of the upward-bulging K-Ti enrichment type; multi-component plots falling within the fields of oceanic island basalts and alkali basalts, belonging to the oceanic island-type volcanic rocks, which are similar to the equivalents in Deqin and Gengma （the Changning-Menglian zone） of Yunnan Province, China.

关 键 词：洋岛玄武岩 地球化学特征 火山岩区 泰国 稀土元素特征 碱性玄武岩 岩石类型 二氧化钛 

分 类 号：P588.13[天文地球—岩石学] P618.51[天文地球—地质学]