NSFGEO-NERC: An Investigation into the Possible Co-evolution of Si and O Isotopes in Igneous Rocks and Minerals From the Hadean to Present

地球的第一个纪元被命名为“冥古宙”，因为地球在大约45.6亿年前形成后的数亿年里一直保持着地狱般的荒凉。 这些模型可能会一直存在，如果不是发现非常古老的晶体从这个Eon。 这些晶体-或特别是矿物锆石（ZrSiO 4）-的年龄可以追溯到大约44亿年前，因此代表了有关最早地球的独特信息来源。 这项研究的主要目标是将保存在这些晶体中的化学信息“翻译”成物理和潜在的行星范围的限制，这些限制专门影响40亿年前地球上发生的水-岩石相互作用。 这是地球上一个有趣的时期，因为地壳或其化学风化成分可能在生命起源中发挥了作用。 这项研究利用了O（氧）和Si（硅）元素具有多种同位素的知识，此外，包括锆石在内的矿物中记录的同位素比率可能会告诉我们地球上发生的水-岩石相互作用的更大谜团的补充故事。 调查开始时将进行：㈠对井控岩石和矿物样品进行高精度的硅和氧同位素测量; ㈡在罗切斯特大学实验地球化学实验室精确控制的环境中进行高压/高温实验。这些信息将用于解释古老锆石晶体的硅和氧同位素地球化学，以新的方式探索地壳循环。该项目的更广泛影响来自对本科生和研究生进行高温/高压实验技术和晶体合成以及使用最先进质谱仪进行同位素分析方面的培训。罗切斯特实验室计划接待来自周边地区的高中科学教师，向他们介绍本研究中使用的技术和科学。 这些研讨会使科学教师接触到尖端的科学技术和数据，他们可以带回课堂。

The first Eon of Earth was named the "Hadean" because of the expectation that Earth would have remained hellish and inhospitable hundreds of millions of years after its formation about 4.56 billion years ago. These models may have persisted, if it were not for the discovery of very ancient crystals from this Eon. These crystals - or specifically the mineral zircon (ZrSiO4) - have ages that extend back to about 4.4 billion years in age, and thus represent a unique source of information about the earliest Earth. The major goal of this research is to 'translate' the chemical information preserved within these crystals into physical and potentially planetary-wide constraints that specifically bear on water-rock interactions occurring on Earth before 4 billion years ago. This was an intriguing time on Earth, because it is likely that the crust or its chemically weathered constituents played a role in the origin of life. The research proposed capitalizes on the knowledge that elements of O (oxygen) and Si (silicon) have multiple isotopes, and furthermore that the isotope ratios recorded in minerals, including zircon, may tell complementary stories of a larger puzzle about water-rock interactions that have occurred on our planet. The investigation will begin by conducting: (i) high precision Si- and O- isotope measurements on well constrained rock and mineral samples; and (ii) high pressure/temperature experiments in the precision-controlled environment of the University of Rochester experimental geochemistry laboratory. This information will be used to interpret the Si- and O- isotope geochemistry of ancient zircon crystals to explore crustal recycling in a new manner. The broader impacts of this project come from the training of undergraduate and graduate students in high temperature/pressure experimental techniques and crystal synthesis, and isotope analysis using state-of-the-art mass spectrometers. The Rochester laboratory plans to host high school science teachers from the surrounding area to introduce them to the technology and the science used in this study. These workshops expose science teachers to cutting edge science and technology and data that they can take back into their classrooms.