Investigation of a new palaeothermometer: High precision isotope ratio measurement of multi-substituted isotopic molecules in carbonates

新型古温度计的研究：碳酸盐中多取代同位素分子的高精度同位素比测量

• 批准号: NE/E010105/1
• 负责人: Paul Dennis
• 金额: $ 6.85万
• 依托单位: University of East Anglia
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FE010105%2F1
• 关键词: Investigation; new; palaeothermometer; precision; isotope

We intend to develop a newly viable and potentially very powerful technique for measuring the temperature at which many different calcium carbonate deposits, such as stalagmites, tufas, mollusc shells and corals, have been formed at various times over the past few hundred thousand years. Potentially this will provide a vast amount of information about the nature of climate change on a global scale and over long time periods. Importantly, many of these types of geological deposits can be very precisely dated by measuring the small amounts of uranium and thorium they contain, and because very small samples (about a milligram) can be used for temperature measurements, it should be possible to obtain temperature records with very high time resolution (probably decadal or less). To achieve the goal we shall use a custom built mass spectrometer, an instrument that is capable of measuring very small differences in the masses of calcium carbonate molecules within the rocks. This is a technically challenging project that will require a lot of experimentation and calibration before it can be used routinely and it is these technical aspects that are the focus of this project. When perfected, this technique will probably have many other geological, mineralogical and hydrothermal applications in addition to investigating past climates.

我们打算开发一种新的可行且可能非常强大的技术，用于测量过去数十万年中不同时期形成的许多不同碳酸钙沉积物的温度，例如石笋、凝灰岩、软体动物贝壳和珊瑚。这可能会提供有关全球范围内长期气候变化性质的大量信息。重要的是，许多此类地质矿床可以通过测量它们所含的少量铀和钍来非常精确地确定年代，并且由于可以使用非常小的样本（大约一毫克）进行温度测量，因此应该可以获得具有非常高时间分辨率（可能十年或更短）的温度记录。为了实现这一目标，我们将使用定制的质谱仪，该仪器能够测量岩石内碳酸钙分子质量的微小差异。这是一个技术上具有挑战性的项目，需要进行大量的实验和校准才能常规使用，而这些技术方面正是该项目的重点。一旦完善，除了调查过去的气候之外，这项技术可能还会有许多其他地质、矿物学和热液应用。