Quantifying Sampling Biases and Silicate-Derived Sr in Continental Runoff: A Coupled 87Sr/86Sr - 88Sr/86Sr Study

量化大陆径流中的采样偏差和硅酸盐衍生的 Sr：87Sr/86Sr - 88Sr/86Sr 耦合研究

基本信息

批准号：
1226818
负责人：
Bernhard Peucker-Ehrenbrink
金额：
$ 34.2万
依托单位：
Woods Hole Oceanographic Institution
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2012
资助国家：
美国
起止时间：
2012-09-01 至 2015-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1226818&HistoricalAwards=false
关键词：
Quantifying Sampling Biases Silicate Derived

项目摘要

The Strontium isotope (87Sr/86Sr) record of seawater is one of the best-reconstructed marine isotope records. It has been widely used to estimate temporal changes of continental and hydrothermal inputs to seawater, and temporal variations have been correlated with periods of glaciations, mountain building and major magmatic events. Despite this impressive record, estimates of the present-day mass balance of strontium in seawater fundamentally disagree, highlighting the challenges of interpreting the marine strontium isotope record.This project aims at investigating how severely present estimates of continental runoff into the ocean are biased, and how such biases can be corrected. The interpretation of the marine record critically hinges on an unbiased understanding of the present-day mass balance and forcing factors. In addition to the radiogenic (87Sr/86Sr) isotope composition, the stable (88Sr/86Sr) isotope signature may yield insights into the balance of silicate- vs carbonate-derived strontium, and thus the balance between silicate and carbonate weathering.The study will be conducted under the umbrella of the Global Rivers Observatory, a collaborative, international network of scientists and community volunteers aimed at observing river systems in time-series fashion. Citizen scientists and REU students will be engaged in sampling representative rivers draining the West and East coasts of North America. Local schools are invited to participate in the "My River, My Home" student art project.

海水的锶同位素 (87Sr/86Sr) 记录是重建得最好的海洋同位素记录之一。它已被广泛用于估计大陆和热液输入海水的时间变化，并且时间变化与冰川作用、造山和主要岩浆事件的周期相关。尽管有这一令人印象深刻的记录，但对目前海水中锶质量平衡的估计根本上不一致，这凸显了解释海洋锶同位素记录的挑战。该项目旨在调查目前对进入海洋的大陆径流的估计有多么严重的偏差，以及如何纠正这种偏见。对海洋记录的解释关键取决于对当今质量平衡和强迫因素的公正理解。除了放射性 (87Sr/86Sr) 同位素组成之外，稳定 (88Sr/86Sr) 同位素特征还可以深入了解硅酸盐与碳酸盐衍生的锶的平衡，从而了解硅酸盐和碳酸盐风化之间的平衡。该研究将全球河流观测站是一个由科学家和社区志愿者组成的国际协作网络，旨在以时间序列方式观测河流系统。公民科学家和 REU 学生将参与对北美西海岸和东海岸的代表性河流进行采样。当地学校受邀参加“我的河，我的家”学生艺术项目。