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应用增量方法计算了氢氧化物族矿物的氧同位素分馏，得到常见氢氧化物的18O富集顺序为：褐铁矿＞三水铝石＞针铁矿＞水镁石＞硬水铝石。氢氧化物与其对应的氧化物相比显著地富集18O。三价阳离子的氢氧化物和氧化物的18O富集顺序为：M（OH）3＞MO（OH）＞M2O3。Al（OH）3同质多象变体之间也存在一定的分馏。对于石英-氢氧化物、方解石-氢氧化物和氢氧化物-水体系，本文计算提供了在0-1200℃温度范围内三组内部一致的分馏系数方程。这些理论校准与合成实验结果和／或地表温度下的天然样品相吻合，特别针铁矿、勃姆石和硬水铝石与水之间的氧同位素分馏关系能够满足地质测温的要求。因此，对氢氧化物-水体系的氧同位素分析可望提供表生环境下可靠的地质温度计。
The oxygen isotope fractionation of the hydroxide minerals is calculated using the incremental method. The 18O enrichment order of the common hydroxides is limonite> gibbsite> goethite> brucite> diaspore. The hydroxide is significantly enriched 18O as compared to its corresponding oxide. The trivalent cation hydroxide and oxide 18O enrichment order: M (OH) 3> MO (OH)> M2O3. There is also some fractionation between Al (OH) 3 homogenous multimodal variants. For the quartz-hydroxide, calcite-hydroxide and hydroxide-water systems, the calculations herein provided three sets of internally consistent fractionation coefficient equations over the temperature range of 0-1200 ° C. These theoretical calibrations coincide with synthetic experimental results and / or natural samples at surface temperatures, and in particular the oxygen isotopic fractionation between goethite, boehmite and diaspore water meets the need for geothermal measurements. Therefore, the oxygen isotope analysis of the hydroxide-water system is expected to provide a reliable geological thermometer in epigenetic environments.