SGER: Calibration of FeTi-Oxide Thermobarometer at 700-900 Degrees Celsius and High Oxygen Fugacity

Evans0000904该项目的主要目标是重新校准铁钛氧化物温度计，以适应中间到中间成分喷发的实际条件。建议的实验工作将在法国奥尔良的CNRS实验室进行，通过在受控的T（700 - 900摄氏度），P和O2（NNO +1至NNO +3）条件下对掺杂有大量但可变量的FeO，TiO 2和MgO的合成流纹岩组合物进行水热平衡。这些实验将建立共存的铁钛铁矿和钛磁铁矿的组合物的依赖性，有和没有镁，T和O2的范围内的问题。 解决方案参数，正确地适应的解决方案的钙钛矿到菱面体的Fe-Ti氧化物将需要适合这些实验。 这项实验工作的结果应该有助于增加这种流行的地质温度计的适用性，以前是适当的组成范围之外的岩石。

Evans0000904This project has as a major goal, to recalibrate the Fe-Ti-oxide thermometer for realistic conditions of eruption of intermediate to silicic compositions. The experimental work proposed will be conducted in the CNRS laboratory in Orleans, France, by hydrothermally equilibrating a synthetic rhyolite composition doped with substantial but variable amounts of FeO, TiO2 and MgO at controlled T (700-900 degrees C), P, and O2 (NNO+1 to NNO+3) conditions. These experiments will establish the composition dependence of coexisting ferrian ilmenite and Ti-magnetite, with and without Mg, on T and O2 in the range in question. Solution parameters that correctly accomodate the solution of geikielite into the rhombohedral Fe-Ti oxide will be required to fit these experiments. The results of this experimental work should help increase the applicability of this popular geothermometer to rocks that were previously outside the appropriate compositional range.