RUI: Investigating Natural Seepage of Light Alkanes from Oil and Natural Gas Deposits

RUI：研究石油和天然气矿藏中轻质烷烃的自然渗漏

• 批准号: 0929004
• 负责人: Lambert Doezema
• 金额: $ 15.21万
• 依托单位: Loyola Marymount University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0929004&HistoricalAwards=false
• 关键词: RUI; Investigating; Natural; Seepage; Light

Because of the importance of hydrocarbons in various facets of atmospheric chemistry, determining where the hydrocarbons come from (sources) and the various pathways by which they are removed from the atmosphere (sinks) is of considerable importance. The total source strength for a particular hydrocarbon over a finite time period (usually a year) can be determined for geographical areas of various sizes - for individual cities, regions, countries, and the planet. One potentially underreported source of methane that has recently attracted attention is geologic emissions, including thermogenically derived seepage. Natural seepage is categorized as macroseepage, which involves outgassing from large vents, or microseepage, which is not visible. Although macroseepage is estimated to be a larger source of methane, microseepage has recently been estimated to be a relatively significant methane source (between 10 and 25 Tg annually). However, this estimation is rough, as the majority of microseepage studies have focused on sites in Europe and a handful of western states. The studies have found a wide range in microseepage fluxes that depend on a variety of factors including season, coastal influence, and a wide variety of geological factors such as soil type, depth of deposit, and proximity of nearby faults. This project will lead to a better understanding of the regional, national, and global budgets of methane and six light alkanes (ethane, propane, n-butane, i-butane, n-pentane, and i-pentane). Specifically, the contribution of oil and natural gas emissions via natural seepage will be quantified using flux chamber measurements for the seven gases. The work on this project is well suited to undergraduates. The students who help build the methane analytical system will learn a great deal about gas chromatography to supplement their knowledge gained in an Instrumental Analysis course. Students that work on the data collection will gain an insight into Atmospheric Chemistry field work and learn how to analyze samples using highly specialized analytical systems. This work will also allow students to learn some aspects of Atmospheric Chemistry, a subject that they are not currently taught at LMU. Students will also work on data analysis, which will include identifying, integrating, and quantifying chromatography peaks and calculating flux rates of different light alkanes. Students will also be fully involved in the dissemination of data including presentations at conferences and writing journal articles.

由于碳氢化合物在大气化学的各个方面的重要性，确定碳氢化合物来自何处（源）以及它们从大气中去除的各种途径（汇）是相当重要的。特定碳氢化合物在有限时间内（通常是一年）的总源强度可以根据不同大小的地理区域--各个城市、地区、国家和地球--来确定。 最近引起注意的一个可能被低估的甲烷来源是地质排放，包括产热渗流。自然渗漏分为宏观渗漏和微观渗漏，前者涉及从大型喷口排出的气体，后者则不可见。虽然宏观渗流估计是一个较大的甲烷来源，但最近估计微观渗流是一个相对重要的甲烷来源（每年10至25 Tg）。然而，这一估计是粗略的，因为大多数微渗漏研究都集中在欧洲和少数西方国家的网站。研究发现，微渗漏通量的范围很广，取决于各种因素，包括季节、海岸影响和各种地质因素，如土壤类型、存款深度和附近断层的接近程度。该项目将使人们更好地了解甲烷和六种轻质烷烃（乙烷、丙烷、正丁烷、异丁烷、正戊烷和异戊烷）的区域、国家和全球预算。具体而言，石油和天然气通过自然渗漏排放的贡献将使用通量室对七种气体进行测量来量化。这个项目的工作非常适合本科生。帮助建立甲烷分析系统的学生将学习大量有关气相色谱的知识，以补充他们在仪器分析课程中获得的知识。从事数据收集工作的学生将深入了解大气化学领域的工作，并学习如何使用高度专业化的分析系统分析样品。这项工作还将使学生学习大气化学的某些方面，这是一个他们目前在LMU没有教授的科目。学生还将从事数据分析，其中包括识别，整合和量化色谱峰，并计算不同轻质烷烃的通量率。学生还将充分参与数据的传播，包括在会议上的演讲和撰写期刊文章。