飞秒激光-三重四级杆ICP-MS准确测定石英和锆石中微量元素钛

石英和锆石的钛温度计为探索复杂地质过程提供了温度制约，但准确测定石英/锆石中钛的含量是该温度计有效利用的前提。作为石英和锆石中的微量元素，钛的激光剥蚀电感耦合等离子质谱（LA-ICP-MS）准确测定存在两个关键技术难点，其一是石英的剥蚀效率低，其二是干扰元素的影响，导致Ti分析精度差（高达30%）。本项目拟利用飞秒激光改善石英的剥蚀行为，并采用三重四级杆质谱（ICP-QQQ-MS）动态反应池技术消除同质异位素（48Ca+、96Zr2+）对48Ti+的干扰，实现高空间分辨率模式下（<30um）石英/锆石中低含量Ti（0.01-10ug/g）的准确分析，为石英/锆石钛温度计在地质研究中的应用提供技术支撑，同时也为原位微区钛同位素分析提供技术借鉴。

Quartz and zircon titanium (Ti) thermometers provide temperature constraints for understanding complex geological processes. However, the precise and accurate determination of Ti contents in quartz/zircon is the prerequisite for applications of this thermometer. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has two bottlenecks: (1) poor ablation behavior of quartz, (2) mass interference on Ti isotopes, resulting less precision (RSD>30%). This project plans to use femtosecond laser to improve the ablation behavior of quartz, and uses the dynamic reaction cell technology of a triple quadrupole mass spectrometry (ICP-QQQ-MS) to eliminate 48Ti+ mass spectrometry interference from 48Ca+, 96Zr2+, and achieve the quantitative analysis of low content Ti (0.01-10ug/g) in quartz/zircon at high spatial resolution mode (<30um). This can provide technical support for the geological application of Ti-in-quartz and Tin-in-zircon thermometers The results of this project will also provide technical references for in-situ micro-determination of Ti isotope analysis.