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对苏州Ａ型花岗岩氢氧同位素组成进行了系统深入的研究，其全岩δ１８Ｏ值为＋３．５‰～＋９．２‰，全岩δＤ值在－８１‰～－５９‰之间变化。主要造岩矿物对保持氧同位素平衡分馏的样品，其Ｄ亏损主要受单阶段岩浆去气机理的制约。部分全岩样品表现出不同程度Ｄ－１８Ｏ同步亏损，这种亏损要受岩浆期后固相线下与外来渗透大气降水之间进行同位素交换机理的制约。石英δ１８Ｏ值基本正常，石英与碱性长石之间氧同位素不平衡分馏特征表明，苏州Ａ型花岗岩整体上起源于亏损１８Ｏ源区物质通过地球动力学再循环产生低δ１８Ｏ岩浆的可能性不大。根据氢氧同位素实测值和理论模型计算结果，推测苏州Ａ型花岗岩浆δＤ和δ１８Ｏ初始值分别为－５０±５‰和７．５±１．０‰，这排除了岩浆起源于曾经历过化学风化循环的地壳上部岩石的可能性。
The hydrogen and oxygen isotopic compositions of type A granites in Suzhou have been studied systematically. The δ18O values of the whole rock range from + 3.5 ‰ to + 9.2 ‰, while the δD values of the whole rocks vary from -81 ‰ to -59 ‰. The major rock-forming minerals are mainly restricted by the single-stage magma degassing mechanism for samples that maintain the equilibrium fractionation of oxygen isotopes. Some whole-rock samples show different levels of D-18O loss, which is controlled by the isotope exchange mechanism between the post-magmatic phase and the external infiltration of atmospheric precipitation. The δ18O values of quartz are basically normal. The characteristics of oxygen isotope unbalanced fractionation between quartz and alkaline feldspar suggest that the A-type granites in Suzhou origin are generally unlikely to have low δ18O magma generated through the Earth’s kinetic recirculation . Based on the measured results of hydrogen and oxygen isotopes and theoretical models, it is speculated that the δD and δ18O initial values of type A granite magmatism in Suzhou are -50 ± 5 ‰ and 7.5 ± 1.0 ‰, respectively. This excludes the origin of magma from the past chemical Weathered circulation of the upper crust rock possibilities.