权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

RUI: Reconstructing ancient terrestrial landscapes of the southeastern Columbia Basin

RUI：重建哥伦比亚盆地东南部的古代陆地景观

基本信息

批准号：
1930835
负责人：
Nicholas Bader
金额：
$ 33.31万
依托单位：
Whitman College
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1930835&HistoricalAwards=false
关键词：
RUI Reconstructing ancient terrestrial landscapes

项目摘要

Landscapes change over geological time as water, wind, and volcanic activity reshape Earth’s surface. In southeastern Washington State, today’s landscape reflects two events of unimaginable size: mammoth eruptions of molten lava and much later, Ice Age mega-floods that scoured and reshaped the landscape. This project focuses on the missing interval between these two events and uses ancient soils to learn about the environment when these ancient landscapes formed. Twelve undergraduate students will be engaged in research experiences that will incorporate field and laboratory techniques that are in wide use in the geosciences.The goal of this research is to characterize terrestrial environments following the eruption of the Columbia River Basalts in southeastern Washington and northeastern Oregon, and to reconstruct the geological processes that shaped the landscape in this area. This will be accomplished by creating a network of field sites across the southeastern Columbia Basin that expose weathered basalt contacts and paleosols. At each site the morphology of the contact and underlying basalt will be characterized, and samples will be collected for lab analyses of micromorphological features and bulk chemical abundances. Lava flows are exposed throughout the region at different elevations, allowing for the study of precipitation gradients and their influence on basalt weathering, and to measure differences in pedogenesis caused by exposure time or thermal diagenesis. These analyses will provide the ability to (i) better understand the timing of Cascade uplift and the subsequent aridification of the Columbia Basin, (ii) reconstruct the landforms caused by periods of glacial outburst flooding that predate the most recent Ice Age floods and (iii) distinguish original soil weathering from post-burial processes. This research will increase understanding of the complex tectonics of the Pacific Northwest and provide insights into the impact of megafloods in shaping the terrestrial landscape.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.

随着水、风和火山活动重塑地球表面，地貌会随着地质时间的推移而发生变化。在华盛顿州东南部，今天的地貌反映了两起规模难以想象的事件：熔岩的猛烈喷发，以及很久以后冰河时代的特大洪水冲刷并重塑了地貌。该项目重点关注这两个事件之间缺失的间隔，并利用古代土壤来了解这些古代景观形成时的环境。十二名本科生将参与研究经验，这些研究经验将结合地球科学中广泛使用的现场和实验室技术。这项研究的目标是描述华盛顿州东南部和俄勒冈州东北部哥伦比亚河玄武岩喷发后的陆地环境特征，并重建塑造该地区景观的地质过程。这将通过在哥伦比亚盆地东南部建立一个暴露风化玄武岩接触面和古土壤的野外场地网络来实现。在每个地点，将对接触面和下面的玄武岩的形态进行表征，并收集样品以用于微形态特征和大量化学丰度的实验室分析。熔岩流暴露在整个地区不同海拔的地方，可以研究降水梯度及其对玄武岩风化的影响，并测量暴露时间或热成岩作用引起的成土差异。这些分析将提供以下能力：（i）更好地了解喀斯喀特隆起的时间和随后哥伦比亚盆地的干旱化，（ii）重建最近一次冰河时代洪水之前的冰川爆发洪水时期造成的地貌，以及（iii）区分原始土壤风化和埋藏后过程。这项研究将增进对太平洋西北地区复杂构造的了解，并深入了解特大洪水对陆地景观影响的影响。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。