Collaborative Research: A New Approach to Detrital Provenance Determination: Application of Laser-Induced Breakdown Spectroscopy (LIBS) to the Tourmaline Supergroup Minerals

合作研究：碎屑来源测定的新方法：激光诱导击穿光谱 (LIBS) 在电气石超族矿物中的应用

• 批准号: 1551415
• 负责人: Nancy McMillan
• 金额: $ 14.84万
• 依托单位: New Mexico State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-15 至 2020-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1551415&HistoricalAwards=false
• 关键词: Collaborative; Research; New; Approach; Detrital

Understanding Earth's geological history provides insight into processes that shape our planet and the distribution of economic resources. However, ancient geological events can be difficult to decipher because their physical presence may be lost to erosion. Fortunately, information on the types and ages of rocks (i.e., their provenance) that were present prior to weathering and erosion are encoded in some minerals that are preserved in sediments and sedimentary rocks. Tourmaline is one such mineral. It is a key repository of geologic information because it incorporates a wide range of chemical elements that reflect the rock environment in which it forms - that is, it encodes the chemical signature of that rock, similar to a fingerprint. Tourmaline is also a chemically and mechanically resistant mineral that, when weathered out of the rock in which it formed, it can become a sand grain that is incorporated into sediments (and rocks). Once it incorporates its original chemical signature, the tourmaline grain stores that signature for millions or billions of years.This work uses a synergistic approach to decipher former geological events, their record in sediments and rocks, by integrating chemical analyses of the mineral tourmaline using the new technology Laser-Induced Breakdown Spectroscopy (LIBS) with the established technology Electron Microprobe analyses (EMP). Both yield in-situ chemical fingerprints: LIBS is advantageous because it collects signals of all elements and their complexes, including the light elements, and provides relative compositions of elements, while EMP is a mature analytical technique and is used for highly precise and accurate micrometer-scale chemical data for most elements (except light elements H, Li). One goal of this work is to use these complementary techniques to develop robust approaches to provenance determination based on an extensive collection of tourmaline samples of known provenance. The provenance techniques will be applied, in a case study, to the geologic development of the East Antarctic Mountains (650-480 million years ago). The goal of this case study is to test the efficacy of tourmaline analysis by LIBS and EMP in deciphering complex geologic history of East Antarctic. This study has two major implications. First, it will develop new avenues of provenance studies to refine our understanding of Earth history using the widespread mineral tourmaline. An additional societal benefit is the potential to differentiate tourmalines from different gem deposits that command radically different prices. Samples, data and techniques from this study will be used in both undergraduate and graduate classes at two minority-serving Universities to educate the next generation of geoscientists. A student exchange between the two universities will broaden their educational and analytical experience, necessary for today?s global workforce. This research team includes two female co-PIs and all PIs serve as mentors to a significant number of women in STEM disciplines. Collaboration with industry brings together academics and industrial partners including a woman-owned for-profit small business, in addition to collaborations with faculty at another undergraduate-focused university.

了解地球的地质历史可以洞悉塑造我们星球和经济资源分布的过程。 但是，古老的地质事件可能很难破译，因为它们的物理存在可能会因侵蚀而失去。幸运的是，在某些保存在沉积物和沉积岩石中的矿物质中编码了有关岩石（即它们的出处）的类型和年龄的信息（即它们的出处）。 电气石就是这样的矿物。它是地质信息的关键存储库，因为它结合了反映其形成的岩石环境的各种化学元素 - 也就是说，它编码该岩石的化学特征，类似于指纹。电气石也是一种化学和机械耐药的矿物，当它从其形成的岩石中风化时，它可以成为砂粒，并将其掺入沉积物（和岩石）中。一旦结合了原始的化学签名，Tourmaline谷物储存了数百万年或数十亿年的签名。这项工作使用新技术激光诱导的分析（LIBS）（EMOUP）（EMOUP）（EMOUP）（EMOUP）将矿物电气石的化学分析（通过将矿物电气石的化学分析集成）通过将矿物电气石的化学分析整合到矿物电视上的化学分析中，以消除以前的地质事件，在沉积物和岩石中的记录。两者都产生原位化学指纹：LIB都是有利的，因为它收集了所有元素及其复合物的信号，包括光元素，并提供了元素的相对组成，而EMP则是一种成熟的分析技术，用于高度精确，精确的微米尺度化学数据，用于大多数元素（光元素H，LI，LI，LI）。这项工作的目标之一是使用这些互补技术来开发强大的方法来基于广泛的已知出处样本收集。 在案例研究中，该出处技术将应用于东南极山脉的地质发展（650-4.8亿年前）。该案例研究的目的是测试Libs和EMP在解密的东南极复杂地质历史中测试电气石分析的功效。 这项研究具有两个主要影响。 首先，它将开发出新的出处研究途径，以完善我们对地球历史的理解，并使用广泛的矿物电气石。额外的社会利益是将巡洋彩与不同价格不同的宝石存款区分开来的潜力。 这项研究的样本，数据和技术将在两所少数派大学的大学的本科和研究生班中使用，以教育下一代地球科学家。 两所大学之间的学生交流将扩大他们的教育和分析经验，这是当今全球劳动力所必需的。该研究小组包括两个女性副作用，所有PI是STEM学科中大量女性的导师。 与行业的合作将学者和工业合作伙伴汇集在一起​​，包括一家妇女拥有的营利性小型企业，除了与教师在另一所专注的大学中与教师合作。