Towards understanding the Behaviour of the Clumped Isotope Signal During Marine Diagenesis; Implication for Reading the Ancient Record

旨在了解海洋成岩作用期间聚集同位素信号的行为；

• 批准号: 1635874
• 负责人: Peter Swart
• 金额: $ 39.95万
• 依托单位: University of Miami
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1635874&HistoricalAwards=false
• 关键词: Towards; understanding; Behaviour; Clumped; Isotope

Reconstruction of the chemical and physical conditions of Earth's early history is often accomplished by analyzing the chemical composition of shallow water sediments. A critical assumption made in such studies is that there have been no significant modifications of the sediments/rocks after they were deposited, and that whatever is measured represents the original conditions present when the sediments were formed. This project aims to test this critical assumption through the use of a relative new and novel geochemical technique, namely the clumped isotope method. Clumped isotopes are combinations of two or more of the rare isotopes of an element. This project will use the clumped isotope method to investigate modern marine sediments and the conditions under which these modern sediments are changed to rock. This will allow previously unavailable information to be obtained from the system under study, namely the temperature of formation. It will also allow an assessment of the chemical records that are used to interpret the early history of Earth. This project provides training for a graduate student as well as research opportunities for undergraduate and high schools students.Specifically, the researchers will measure clumping of C and O isotopes (delta47) in a variety of different types of modern carbonate sediments and trace this signature through recrystallization in the marine burial realm. Significant headway has already been made into characterizing the clumped isotopic signal in modern carbonate sediments of differing types, and preliminary data suggest a difference between skeletal and non-skeletal dominated sediments. The goals of this work are to: (i) examine in more detail the difference in the delta47 of various type of modern allochems and how these control the delta47 of the bulk sediments, and (ii) study the diagenetic behaviour using delta47 along transects at two different carbonate margins, one dominated by non-skeletal production (ODP Sites 1003, 1005, and 1006) located off the western margin of the Bahamas), and one dominated by skeletal sediments (Maldives (IODP Sites U1466-68) and/or the Great Barrier Reef (Sites 819- 823). These data will be compared with a pelagic site (Site 807). The rates of diagenesis using the delta47 will be modelled and compared with rates determined from other geochemical proxies, including Sr, Ca, and O isotopes. This work will build on 30 years of ODP cruises (Legs 101-359) and interactions and collaborations with young scientists using other novel tracers of diagenesis.

地球早期历史的化学和物理状况的重建通常是通过分析浅水沉积物的化学成分来完成的。 在此类研究中做出的一个关键假设是，沉积物被沉积后没有显着修改，并且所测量的任何测量代表形成沉积物时存在的原始条件。该项目旨在通过使用相对新颖的地球化学技术来测试这一关键假设，即块状同位素方法。 集成的同位素是两个或多个元素稀有同位素的组合。 该项目将使用汇总的同位素方法研究现代海洋沉积物以及这些现代沉积物更改为岩石的条件。这将允许从所研究的系统中获得以前无法获得的信息，即形成温度。 它还将允许评估用于解释地球早期历史的化学记录。该项目为研究生提供了培训，并为本科和高中学生提供了研究机会。特别是，研究人员将在各种不同类型的现代碳酸盐沉积物中测量C和O同位素（Delta47）的团块，并通过海洋埋葬领域的再结晶来追踪此签名。 已经在表征不同类型的现代碳酸盐沉积物中的集结同位素信号已经取得了显着的进展，而初步数据表明骨骼和非骨骼主导的沉积物之间存在差异。 这项工作的目标是：（i）更详细地检查各种现代同种类型的Delta47的差异以及它们如何控制大块沉积物的delta47，以及（ii）研究使用Delta47沿两种不同的碳酸盐边际上的Delta47沿两种不同的碳酸盐边缘统治的Delta47，一种由非skelet the Production Producte of Prodip of Propofuct of-Skelet Producte odp thep thep thep thep ofp thep sere ofp sere seres 1003，和1003，和1003，和1003，和1003，和1003，及其巴哈马），其中一个以骨骼沉积物为主（MALDIVE（IODP站点U1466-68）和/或/或大屏障礁（地点819-823）。将将这些数据与pelagic网站进行比较（现场807）（807）。使用Delta47的成分和其他速度相比，与其他Geochem相比，将其与其他Geochem进行比较。同位素。这项工作将建立在30年的ODP巡航（腿101-359）上，并使用其他新型的成岩作用示踪剂与年轻科学家进行互动和合作。

项目成果

Origin of blocky aragonite cement in Cenozoic glaciomarine sediments, McMurdo Sound, Antarctica

• DOI: 10.1111/sed.12690
• 发表时间: 2019-12
• 期刊: Sedimentology
• 影响因子: 3.5
• 作者: Mingyu Yang;T. Frank;C. Fielding;M. Smith;P. Swart

An abrupt Middle-Miocene increase in fluid flow into the Leeward Margin Great Bahama Bank, constraints from δ44Ca and Δ47 values

中中新世流入背风边缘大巴哈马浅滩的流体流量突然增加，受到 44Ca 和 47 值的限制

• DOI: 10.1016/j.epsl.2020.116625
• 发表时间: 2021
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Staudigel, Philip T.;Higgins, John A.;Swart, Peter K.
• 通讯作者: Swart, Peter K.

Geochemical fingerprints of dolomitization in Bahamian carbonates: Evidence from sulphur, calcium, magnesium and clumped isotopes

• DOI: 10.1111/sed.12775
• 发表时间: 2020-08
• 期刊: Sedimentology
• 影响因子: 3.5
• 作者: S. Murray;J. Higgins;C. Holmden;Chaojin Lu;P. Swart

Cryogenic brines as diagenetic fluids: Reconstructing the diagenetic history of the Victoria Land Basin using clumped isotopes

• DOI: 10.1016/j.gca.2018.01.002
• 发表时间: 2018-03
• 期刊: Geochimica et Cosmochimica Acta
• 影响因子: 5
• 作者: P. Staudigel;S. Murray;D. Dunham;T. Frank;C. Fielding;P. Swart

A diagenetic origin for isotopic variability of sediments deposited on the margin of Great Bahama Bank, insights from clumped isotopes

• DOI: 10.1016/j.gca.2019.05.002
• 发表时间: 2019-08
• 期刊: Geochimica et Cosmochimica Acta
• 影响因子: 5
• 作者: P. Staudigel;P. Swart