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根据对现有氧扩散模型的解析分析 ,通过模拟矿物之间的氧同位素交换轨迹进行模式温度计算 ,改进了常规矿物对氧同位素地质温度计方法。将模式温度计算与矿物氧扩散封闭次序规则相结合 ,建立了一个系统独立的氧同位素温度计算方法 ,因此所得到的同位素温度能够更好地反映矿物在高温岩石冷却过程中的氧同位素交换行为。模式温度计算有如下优点 :( 1)考虑到了矿物之间氧扩散引起的同位素交换 ;( 2 )遵循质量守恒原理 ,更严格地适用于有限封闭体系 ;( 3)能够恢复岩石的高温历史 ;( 4)基本不依赖于具体的扩散模型 ;( 5 )地质含义更加明确 ,适用范围更广。通过对假想的封闭花岗岩体系、San Jose英云闪长岩和 Sybille采场橄长岩的实例分析可以看出 ,模式温度计算有良好的自洽性和应用前景。对大别山双河两种片麻岩所进行的模式温度计算得到副片麻岩中石榴石和榍石的模式温度为 6 95～ 930℃ ,正片麻岩中石榴石和磁铁矿的模式温度为 5 6 0～ 75 0℃。在高温下的降温阶段 ,副片麻岩与正片麻岩可能有着不同的冷却历史 ,但两种片麻岩可能均经历过榴辉岩相温度的变质作用
Based on the analysis of the existing oxygen diffusion model, the method of calculating the temperature of the model by simulating the oxygen isotope exchange between minerals is proposed, which improves the method of conventional mineral oxygen isotope geology thermometer. Combining the model temperature calculation with the rule of Oxygen diffusion closed order, a system independent calculation of oxygen isotope temperature was established. Therefore, the obtained isotope temperature can better reflect the oxygen isotope exchange behavior of minerals during cooling of high temperature rocks. Mode temperature calculation has the following advantages: (1) Consideration of isotope exchange due to oxygen diffusion between minerals; (2) Compliance with the principle of conservation of mass for more limited application to a limited confinement system; (3) 4) Basically do not depend on the specific diffusion model; (5) More clear geological meaning, wider scope of application. Through the example analysis of the hypothetical closed granite system, San Jose diorite and Sybille stope, we can see that the calculation of mode temperature has good self-consistency and application prospect. The model temperature of two types of gneisses in Shuanghe, Dabieshan Mountains is calculated as follows: the mode temperature of garnet and gallstone in paragneiss is 695 ~ 930 ℃; the mode temperature of garnet and magnetite in orthogneiss is 5 6 0 ~ 75 0 ℃. There may be different cooling history between paragneiss and orthogneiss in the cooling stage at high temperature, but both gneiss may have experienced metamorphism of eclogite temperature