Collaborative Research: Assessing the Sensitivity of High-altitude Environments to Globally Warm Climate as Recorded by Lacustrine Microbialite Carbonates

合作研究：评估湖相微生物碳酸盐记录的高海拔环境对全球温暖气候的敏感性

• 批准号: 1826869
• 负责人: Carie Frantz
• 金额: $ 11.06万
• 依托单位: Weber State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1826869&HistoricalAwards=false
• 关键词: Collaborative; Research; Assessing; Sensitivity; altitude

This project will reconstruct a high elevation environment during the globally warm period between ~70 and 50 million years ago. Researchers have little information about high elevation sites during past periods of increased global temperature, although modern high elevation settings appear to be highly sensitive to rapid changes in climate. We are focusing our research on the Sheep Pass Formation, which is interpreted to have been deposited in a high elevation, fresh water lake system. The project will initially provide a better estimate of the age of the Sheep Pass Formation, which is important since there are few stratigraphic records that capture this time interval in this region. A better estimate of the age of the Sheep Pass Formation may enable development of new records of rapid climate change during the Paleogene, which was one of the warmest times in Earth's history and was marked by numerous rapid, short-term warming events known as hyperthermals. We also expect to improve estimates of the elevation of this region at the time of creation of the rocks. Finally, this project will provide new information about how these rocks form in lakes today and are altered after creation, which will improve how researchers interpret ancient climate from other rocks like these. This project is timely and serves the national interest because we need to better understand how the western US, much of which is at higher elevations, will respond to future environmental change. For example, this project may help us better understand threats to the water supply in the western US, as well as potential for estimating how much temperatures may change in these regions relative to global estimates. In addition, the Sheep Pass Formation contains some oil. This project will produce better understanding of the history of these rocks after they were created, which will give us more information on the changes that may have allowed oil to migrate into the rocks, giving us more insight into potential oil resources in similar types of rocks.Most modern high elevation regions are warming faster than lower elevation regions at similar latitudes, which in turn affects water resources and ecosystems in those regions. However, the mechanisms driving this increase in temperature are unclear. The snow-albedo feedback is often invoked as a major contribution to this effect, but this mechanism would not apply during 'greenhouse' times in the past with little to no ice at the poles or high elevations, such as the Cretaceous and Paleogene. Study of high elevation regions during greenhouse climates may provide insight into their sensitivity to globally warm climate, and help elucidate the fundamental mechanism(s) driving the phenomenon. Additionally, intermontane basins have yielded most of the existing terrestrial records of greenhouse climate and hyperthermals to-date (e.g. the Paleocene-Eocene Thermal Maximum-PETM). Thus, better knowledge of how these regions respond to warming will improve comparisons of terrestrial paleoclimate records to marine records and help resolve sources of discrepancy between them. This project focuses on the Late Cretaceous-middle Eocene Sheep Pass Formation (SPF) in central Nevada, which was at least 2 km high at the time of deposition. The SPF preserves a thick succession of lacustrine microbialite carbonate suitable for stable isotope analysis, and the age of the SPF suggests that it may preserve the K-Pg boundary, the PETM, and other Early Eocene rapid warming events. However, age constraint is limited, so we are using magnetostratigraphy and calcite U/Pb geochronology to improve the chronostratigraphic framework. In addition, we are characterizing the microbialite sedimentology and generating a comprehensive suite of traditional and 'clumped' stable isotope values at better than 0.5 m.y resolution. To better understand the role of microbes in lacustrine carbonate precipitation and alteration, we are sampling modern microbialites in three alkaline lakes in North America that span diverse environments and climates. We are developing traditional and clumped isotope datasets of sediments and porewaters; detailed sediment microfacies descriptions; lake water and porewater carbonate chemistry datasets; and 16S rRNA gene amplicon sequencing of surface and shallow subsurface microbial communities. We will combine these datasets into an interpretive framework for lacustrine microbialites that we will apply to the SPF to assess how high elevation environments responded to globally warm conditions. This project is advancing discovery and understanding of science through the training and mentoring of undergraduate and graduate students and a postdoctoral researcher.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.

该项目将重建7000万至5000万年前全球温暖时期的高海拔环境。研究人员对过去全球气温升高时期的高海拔地区几乎没有了解，尽管现代高海拔地区似乎对气候的快速变化非常敏感。我们的研究重点是羊肠小道地层，据解释，这是一个高海拔的淡水湖泊系统沉积。该项目最初将提供一个更好的估计年龄的绵羊通过形成，这是很重要的，因为有几个地层记录，捕捉这个时间间隔在这个地区。更好地估计绵羊通道地层的年龄可能有助于开发古近纪快速气候变化的新记录，古近纪是地球历史上最温暖的时期之一，其标志是许多快速，短期的变暖事件，称为高温。我们还希望改善对岩石形成时该地区海拔的估计。最后，该项目将提供有关这些岩石如何在今天的湖泊中形成以及在创建后发生变化的新信息，这将改善研究人员如何从其他岩石中解释古代气候。这个项目是及时的，符合国家利益，因为我们需要更好地了解美国西部，其中大部分是在较高的海拔，将如何应对未来的环境变化。例如，该项目可以帮助我们更好地了解美国西部供水面临的威胁，以及估计这些地区相对于全球估计的温度变化的潜力。此外，羊肠小道地层还含有一些石油。该项目将更好地了解这些岩石形成后的历史，这将为我们提供更多关于可能使石油迁移到岩石中的变化的信息，使我们更深入地了解类似类型岩石中的潜在石油资源。大多数现代高海拔地区比类似纬度的低海拔地区变暖更快，这反过来又影响到这些地区的水资源和生态系统。然而，驱动这种温度升高的机制尚不清楚。雪-冰反馈通常被认为是对这种效应的主要贡献，但这种机制在过去的“温室”时期并不适用，因为在两极或高海拔地区几乎没有冰，如白垩纪和古近纪。研究高海拔地区在温室气候条件下的变化，可以深入了解它们对全球变暖气候的敏感性，并有助于阐明驱动这一现象的基本机制。此外，山间盆地已经产生了大多数现有的温室气候和高温的陆地记录（如古新世-始新世热极大期-PETM）。因此，更好地了解这些地区如何应对变暖将改善陆地古气候记录与海洋记录的比较，并有助于解决它们之间的差异来源。本项目的重点是内华达州中部的晚白垩世-中始新世羊道组（SPF），沉积时至少有2 km高。SPF保存了一个厚厚的湖相微生物碳酸盐的继承适合稳定同位素分析，SPF的年龄表明，它可能会保存K-Pg边界，PETM，和其他早始新世快速变暖事件。然而，年龄约束是有限的，所以我们正在使用磁性地层学和方解石U/Pb年代学来改善年代地层格架。此外，我们正在表征微生物岩沉积学，并生成一套全面的传统和“聚集”稳定同位素值，分辨率优于0.5百万年。为了更好地了解微生物在湖泊碳酸盐沉淀和蚀变中的作用，我们正在北美三个碱性湖泊中对现代微生物岩进行采样，这些湖泊跨越了不同的环境和气候。我们正在开发沉积物和孔隙水的传统和聚集的同位素数据集;详细的沉积物微相描述;湖水和孔隙水碳酸盐化学数据集;以及地表和浅层地下微生物群落的16 S rRNA基因扩增子测序。我们将联合收割机将这些数据集结合成一个解释框架，我们将应用于SPF，以评估高海拔环境如何应对全球变暖的条件。该项目通过对本科生、研究生和博士后研究人员的培训和指导，推进科学的发现和理解。该奖项反映了NSF的法定使命，并通过使用基金会的智力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

Desiccation of ecosystem-critical microbialites in the shrinking Great Salt Lake, Utah (USA)

• DOI: 10.1371/journal.pwat.0000100
• 发表时间: 2023-09
• 期刊: PLOS Water
• 作者: Carie Frantz;Cecilia Gibby;R. Nilson;Cole J. Stern;Maggie Nguyen;Cody Ellsworth;Hank Dolan;Alvin Sihapanya;Jake Aeschlimann;Bonnie K. Baxter

DOCUMENTING A GEOBIOLOGICAL TRAGEDY: THE EXPOSURE OF GREAT SALT LAKE'S MICROBIALITES AND THE UNDERGRADUATE RESEARCHERS AT THE VANGUARD

记录地球生物学悲剧：大盐湖微生物的暴露和先锋队的本科研究人员

• DOI: 10.1130/abs/2022am-383654
• 发表时间: 2022
• 期刊: Geological Society of America Abstracts with Programs
• 作者: Frantz, Carie;Gibby, Cecilia;Gibby, Cecilia;Nilson, Rebekah;Nilson, Rebekah;Aeschlimann, Jake;Aeschlimann, Jake;Athalye, Roxolana;Athalye, Roxolana;Christensen, Caitlin
• 通讯作者: Christensen, Caitlin

EFFECT OF EXPOSURE AND DESICCATION ON MINERALIZATION OF GREAT SALT LAKE MICROBIALITES

暴露和干燥对大盐湖微生物矿化的影响

• DOI: 10.1130/abs/2022am-381141
• 发表时间: 2022
• 期刊: Geological Society of America Abstracts with Programs
• 作者: Stern, Cole;Degrange, Aybree;Frantz, Carie
• 通讯作者: Frantz, Carie