Rethinking carbonate diagenesis: clues to past carbon cycling from an overlooked carbon sink

重新思考碳酸盐成岩作用：从被忽视的碳汇中寻找过去碳循环的线索

• 批准号: NE/L011050/2
• 负责人: Sarah Greene
• 金额: $ 29.59万
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FL011050%2F2
• 关键词: Rethinking; carbonate; diagenesis; clues; past

Over geological timescales carbon is recycled through the atmosphere, the biosphere, the ocean, and even gets incorporated into sedimentary rock; this movement of carbon between reservoirs is colloquially called the 'carbon cycle.' Carbon in the rock record can be preserved as organic (biological) molecules or inorganic molecules of calcium carbonate, also known as limestone. By studying the chemical differences between the carbon in these organic and inorganic carbon compounds, we can reconstruct aspects of the history of life, past changes in climate, and even the history of the oxygenation of Earth's atmosphere.Recently, we have recognised that the way we read geologic history may be vastly influenced by a third type of carbon in the rock record. 'Diagenetic carbonate' is made of the same mineral as limestone, but forms from decomposed organic carbon. Its carbon, therefore, can be more chemically similar to the organic carbon from which it forms. A better understanding of the amount of carbon stored as diagenetic carbonate during earth's history could fundamentally change the answers to questions relating to past oxygen levels and past climate changes. Indeed, diagenetic carbonate certainly seems to be more common in the rock record than it is in the modern ocean - for example much of the limestone at Britain's most popular fossil tourism sites is diagenetic carbonate, including parts of the Dorset, Somerset, Yorkshire, and Glamorgan coastlines. Unfortunately, our understanding of the production of diagenetic carbonate during various geologic periods is in its infancy. The formation of diagenetic carbonate is governed by the interactions of many different chemical processes in the ocean sediment. Therefore, to decipher when, why, and how much diagenetic carbonate is produced under different environmental and oceanic conditions, I will use state of the art computer modelling to answer these questions. In light of the resulting calculations, I will be able to reinterpret aspects of past climates, abrupt climate change and the history of the oxygenation of Earth's atmosphere.In addition to this, I will also be conducting field work at sites with abundant diagenetic carbonate (including those on the Somerset and Yorkshire coasts) and measuring the chemistry of the diagenetic carbonates. With this information, the computer models I use will then be able to rewind the sedimentary record to decipher what kinds of environmental factors led to the formation of these diagenetic carbonates. The Somerset coast contains the records of a mass extinction and the Yorkshire coast the records of a time when the ocean was extremely low in oxygen. The information that the diagenetic carbonates provide about the past environments will helps us unravel the causes and consequences of these past episodes of rapid climate change. This new and exciting method to learn about the past from diagenetic carbonate, an untapped archive of past climates, can then be applied to all sorts of other episodes of climate change in Earth history.This fellowship answers a call in the field of palaeoclimate science for interdisciplinarity. We can learn much more by combining the power of modelling with exciting new field and laboratory observations. I have designed a fellowship research plan which integrates and augments my skills in field and lab geology as well as climate modelling, and assembled a cast of collaborators who are world leaders in their respective fields. This project will serve as a model to geoscientists studying the history of life and climate for how modelling and data approaches can be combined in a new, powerful way.

在地质时间尺度上，碳在大气、生物圈、海洋中循环，甚至进入沉积岩;碳在储层之间的这种运动俗称为“碳循环”。岩石记录中的碳可以作为有机（生物）分子或碳酸钙的无机分子保存下来，也被称为石灰石。通过研究这些有机和无机碳化合物中碳的化学差异，我们可以重建生命历史的各个方面，过去的气候变化，甚至地球大气的氧化历史。最近，我们认识到，我们阅读地质历史的方式可能会受到岩石记录中第三种碳的巨大影响。“成岩碳酸盐”由与石灰石相同的矿物组成，但由分解的有机碳形成。因此，它的碳在化学上可能与形成它的有机碳更相似。更好地了解地球历史上以成岩碳酸盐形式储存的碳的数量，可能会从根本上改变与过去氧气水平和过去气候变化有关的问题的答案。事实上，成岩碳酸盐在岩石记录中似乎比在现代海洋中更常见--例如，英国最受欢迎的化石旅游景点中的大部分石灰石都是成岩碳酸盐，包括多塞特、萨默塞特、约克郡和格拉摩根海岸线的部分地区。不幸的是，我们对不同地质时期成岩碳酸盐的认识还处于初级阶段。成岩碳酸盐的形成受海洋沉积物中许多不同化学过程的相互作用控制。因此，为了解释在不同的环境和海洋条件下何时、为何以及有多少成岩碳酸盐产生，我将使用最先进的计算机建模来回答这些问题。根据计算结果，我将能够重新解释过去的气候、气候突变和地球大气氧化的历史。除此之外，我还将在具有丰富成岩碳酸盐的地点（包括萨默塞特和约克郡海岸）进行实地考察，并测量成岩碳酸盐的化学性质。有了这些信息，我使用的计算机模型将能够倒回沉积记录，以破译什么样的环境因素导致了这些成岩碳酸盐的形成。萨默塞特海岸记录了一次大规模灭绝，约克郡海岸记录了一段海洋含氧量极低的时期。成岩碳酸盐提供的关于过去环境的信息将帮助我们解开这些过去快速气候变化事件的原因和后果。这种新的和令人兴奋的方法来了解过去的成岩碳酸盐，一个未开发的档案过去的气候，然后可以应用到各种其他事件的气候变化在地球历史上。这个奖学金响应呼吁在古气候科学领域的跨学科。我们可以通过将建模的力量与令人兴奋的新领域和实验室观察相结合来了解更多。我设计了一个奖学金研究计划，它整合和增强了我在野外和实验室地质学以及气候建模方面的技能，并组建了一批在各自领域处于世界领先地位的合作者。该项目将作为地球科学家研究生命和气候历史的一个模型，以了解建模和数据方法如何以一种新的、强大的方式结合起来。

项目成果

Getting the basics right: a field-teaching primer on toilet stops in the field

掌握正确的基础知识：关于现场厕所站的现场教学入门

• DOI: 10.5194/egusphere-egu2020-11723
• 发表时间: 2020
• 作者: Giles S

OPTiMAL: a new machine learning approach for GDGT-based palaeothermometry

• DOI: 10.5194/cp-2019-60
• 发表时间: 2019-06
• 期刊: Climate of the Past
• 影响因子: 4.3
• 作者: T. Dunkley Jones;Y. Eley;W. Thomson;S. Greene;I. Mandel;K. Edgar;J. Bendle

Inclusion of a suite of weathering tracers in the cGENIE Earth system model – muffin release v.0.9.23

• DOI: 10.5194/gmd-14-4187-2021
• 发表时间: 2021-07
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: Markus Adloff;A. Ridgwell;F. Monteiro;I. Parkinson;A. Dickson;Philip A. E. Pogge von Strandmann;M. Fantle;S. Greene

Unravelling the sources of carbon emissions at the onset of Oceanic Anoxic Event (OAE) 1a

• DOI: 10.1016/j.epsl.2019.115947
• 发表时间: 2020-01-15
• 期刊: EARTH AND PLANETARY SCIENCE LETTERS
• 影响因子: 5.3
• 作者: Adloff, Markus;Greene, Sarah E.;Monteiro, Fanny M.
• 通讯作者: Monteiro, Fanny M.

Safety and Belonging in the Field: A Checklist for Educators

现场安全和归属感：教育工作者清单

• DOI: 10.31223/x53p6h
• 发表时间: 2023
• 作者: Greene S