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对乔治王岛１１个火山岩和２个侵入岩样品做了Ｓｒ－Ｎｄ－Ｐｂ同位素分析，其中（８７Ｓｒ／８６Ｓｒ）ｉ＝０．７０３２６～０．７０３９２，εＮｄ＝３．０２～６．７２，２０６Ｐｂ／２０４Ｐｂ＝１７．７７６～１８．５１５，２０７Ｐｂ／２０４Ｐｂ＝１５．．５０６～１５．５７１，２０８Ｐｂ／２０４Ｐｂ＝３７．８６８～３８．３０８。根据以上同位素组成及其相互关系并结合岩石学和微量元素特征及火山岩中熔融包裹体成分，得出以下结论：（１）研究的乔治王岛岩浆岩起源于亏损地幔（ＤＭＭ）和地幔流体交代成因的富集地幔ＥＭＩ混合形成的源区；（２）该源区具有广义Ｄｕｐａｌ异常，它正是由于ＥＭＩ组份加入即通过流体交代作用而产生的；（３）流体主要是俯冲深海沉积物脱碳酸盐作用而释放出的富ＣＯ２流体。
Sr-Nd-Pb isotopic analyzes of eleven volcanic rocks and two intrusive rocks in the island of King George, with (87Sr / 86Sr) i = 0.70326 to 0.70392 and εNd = 3.02 to 6.72 and 206Pb /204Pb=17.776~18.515,207Pb/204Pb=15. . 506 to 15.571, 208Pb / 204Pb = 37.868 to 38.308. Based on the above isotopic compositions and their interrelationships with the petrologic and trace element characteristics and the composition of the melt inclusions in volcanic rocks, the following conclusions can be drawn: (1) The GEO magmatic rocks originated from depleted mantle (DMM) and mantle fluid (2) the source region has a generalized Dupal anomaly, which is due to the EMI component added by fluid metasomatism; (3) the fluid is mainly subducted deep-sea sediments CO2-rich fluid released by decarbonation.