CAREER: Carbon storage in widespread low-saturation gas hydrate systems

职业：广泛的低饱和天然气水合物系统中的碳储存

• 批准号: 1752882
• 负责人: Ann Cook
• 金额: $ 61.58万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-01 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1752882&HistoricalAwards=false
• 关键词: CAREER; Carbon; storage; widespread; low

Natural gas hydrates are minerals that look like ice, but contain a highly concentrated amount of methane, also known as natural gas. Natural gas hydrates form on the seafloor and in marine sediments beneath the seafloor when water depths exceed ~500 m. Worldwide, marine methane gas hydrates are estimated to store 20% to 50% of Earth?s mobile carbon. Perturbations to temperature and pressure cause gas hydrates to dissociate into methane gas and water. Due to the large reservoir of carbon in methane gas hydrates, the metastability of these minerals, and the fact that methane is a strong greenhouse gas, many scientists have theorized that methane liberated from natural gas hydrates may be a key player in many of Earth?s large global warming events. However, the amount of gas hydrate locked in marine sediments is not well known, with present estimates varying by four orders of magnitude. This research uses well logs from publicly accessible academic and industry geophysical information and well logs from cores drilled into marine sediments in conjunction with new mathematical approaches to evaluate, model, and estimate the amount of methane gas hydrates in a broad spectrum of different marine settings. This information is then used to provide crucial, first-time information on the occurrence, distribution, amount of naturally occurring methane gas hydrates in the seafloor, worldwide. Broader impacts of the work include information that can be used by the petroleum and natural gas industry in discovering and assessing economically feasible natural gas occurrences; the integration of research and education involving large numbers of students who will be involved in the data analysis and interpretation parts of the project; will complement previous gas hydrate assessments in the Gulf of Mexico; and complements a pending research cruise funded by the National Science Foundation- supported International Ocean Discovery Program. The research will help support an investigator whose demographic is underrepresented in the sciences, will support the development of video field trips, and provide important information to students on careers in geology outside of academia. The assessments and estimates of natural methane gas hydrates are based on already existing data from petroleum industry geophysical well logs from offshore locations worldwide that already exists, but has not been systematically analyzed for natural gas hydrate. As a matter of course in exploration studies, the petroleum industry collects well log data in the shallow interval that coincides with gas hydrate stability, but often ignores it because their interest in in deeper seated major liquid petroleum plays, not gas hydrate occurrences. Up to now, scientists have not exploited this vast treasure trove of data. This research project focuses on these valuable, but underutilized data. Research will involve the investigator, her graduate students, and her Borehole Geophysics class. They will examine and analyze well logs from the north Atlantic, the North Sea, offshore Western Australia, and the Gulf of Mexico using novel mathematical and conceptual tools that combine the petrophysical analysis of petroleum industry well logs with numerical modeling and geochemistry measurements to help constrain and understand the distribution and saturation of natural gas hydrates worldwide. The resulting information will be used to inform global climate models and provide accurate information on the influence of gas hydrate on global climate change.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

天然气水合物是一种看起来像冰的矿物质，但含有高度浓缩的甲烷，也称为天然气。当水深超过~500 m时，天然气水合物在海底和海底下的海洋沉积物中形成。全球范围内，海洋甲烷水合物估计储存了地球的20%到50%。是移动的碳。温度和压力的扰动导致天然气水合物分解成甲烷气体和水。由于甲烷气体水合物中碳的大量储存，这些矿物的亚稳定性，以及甲烷是一种强烈的温室气体的事实，许多科学家推测，从天然气水合物中释放的甲烷可能是地球上许多生物的关键角色。大规模的全球变暖事件。 然而，海洋沉积物中锁定的天然气水合物的数量尚不清楚，目前的估计值相差四个数量级。这项研究使用来自公开获取的学术和工业地球物理信息的测井记录，以及钻探到海洋沉积物中的岩心的测井记录，并结合新的数学方法来评估，建模和估计各种不同海洋环境中甲烷水合物的数量。 然后，这些信息被用来提供关于全球海底天然甲烷水合物的发生、分布和数量的关键的第一时间信息。 这项工作的更广泛影响包括：石油和天然气工业可用于发现和评估经济上可行的天然气矿点的信息;将研究和教育结合起来，涉及大量学生，他们将参与项目的数据分析和解释部分;将补充以前对墨西哥湾天然气水合物的评估;并补充了一个由国家科学基金会支持的国际海洋发现计划资助的悬而未决的研究巡航。 这项研究将有助于支持其人口在科学中代表性不足的调查员，将支持视频实地考察的发展，并为学生提供学术界以外的地质学职业的重要信息。 天然甲烷气水合物的评估和估计是基于来自世界各地海上石油工业地球物理测井的现有数据，这些数据已经存在，但尚未对天然气水合物进行系统分析。在勘探研究中，石油工业当然会收集与天然气水合物稳定性相一致的浅层测井数据，但通常会忽略它，因为他们感兴趣的是更深层的主要液体石油区带，而不是天然气水合物的出现。 到目前为止，科学家们还没有利用这个巨大的数据宝库。 这个研究项目的重点是这些有价值的，但未充分利用的数据。 研究将涉及调查员，她的研究生，和她的钻孔地球物理类。他们将检查和分析来自北大西洋，北海，西澳大利亚近海和墨西哥湾的测井记录，使用新的数学和概念工具，将石油工业测井记录的岩石物理分析与数值建模和地球化学测量相结合，以帮助限制和了解全球天然气水合物的分布和饱和度。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Hydrate‐filled Fracture Formation at Keathley Canyon 151, Gulf of Mexico, and Implications for Non‐vent Sites

• DOI: 10.1029/2019gc008637
• 发表时间: 2019-11
• 期刊: Geochemistry
• 影响因子: 3.7
• 作者: E. Oti;A. Cook;S. Welch;J. Sheets;D. Crandall;K. Rose;H. Daigle

Physical Properties and Gas Hydrate at a Near‐Seafloor Thrust Fault, Hikurangi Margin, New Zealand

• DOI: 10.1029/2020gl088474
• 发表时间: 2020-08
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: A. Cook;M. Paganoni;M. Clennell;D. Mcnamara;M. Nole;Xiujuan Wang;Shuoshuo Han;R. Bell;E. Solomon;D. Saffer;P. Barnes;I. Pecher;L. Wallace;L. Levay;K. Petronotis

Widespread subseafloor gas hydrate in the Barents Sea and Norwegian Margin

巴伦支海和挪威边缘广泛分布的海底天然气水合物

• DOI: 10.1016/j.epsl.2023.117993
• 发表时间: 2023
• 期刊: Earth and Planetary Science Letters
• 影响因子: 5.3
• 作者: Cook, A.E.;Portnov, A.;Heber, R.C.;Vadakkepuliyambatta, S.;Bünz, S.
• 通讯作者: Bünz, S.

Diverse gas composition controls the Moby-Dick gas hydrate system in the Gulf of Mexico

不同的气体成分控制着墨西哥湾的莫比迪克天然气水合物系统

• DOI: 10.1130/g49310.1
• 发表时间: 2021
• 期刊: Geology
• 影响因子: 5.8
• 作者: Portnov, Alexey;Cook, A.E.;Vadakkepuliyambatta, S.
• 通讯作者: Vadakkepuliyambatta, S.