Heat Budget in the Hyporheic Zone of a Large, Gravel-Bed River

大型砾石床河潜流区的热量收支

• 批准号: 0538075
• 负责人: Stephen Lancaster
• 金额: --
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-15 至 2009-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0538075&HistoricalAwards=false
• 关键词: Heat; Budget; Hyporheic; Zone; Large

This project is a quantitative physics-based study of the heat budget in the hyporheic zone of a large river. It is relevant to current research in the interactions between stream temperature and hyporheic water flux. Understanding heat transfer in hyporheic zones has important implications for water quality and its regulation in the western US, and may be a new tool for researchers, regulators, and water treatment professionals. Preliminary results indicate that warm river water undergoes hyporheic cooling during its transit beneath gravel bars. River-restoration and pollution-credit-trading schemes are being designed around hyporheic cooling strategies, and this makes a full understanding of this phenomenon an imperative. Initial hypotheses include: (1) warm, daytime water is not actually cooled in the hyporheic zone but does push out cool, nighttime water during the day, (2) warm, daytime water is significantly cooled by a) heat flow by conduction to and mixing with deeper groundwater with longer flow paths, b) heat flow by latent and sensible heat fluxes to the vadose zone, and/or c) temporary heat storage in gravels and dead zones in the hyporheic zone. Preliminary tests of these hypotheses will be accomplished through field instrumentation and modeling of water and heat fluxes beneath a gravel bar on a large, gravel-bed river, the Willamette River, Oregon. The research site represents a recently deposited gravel bar of the type found to provide significant apparent cooling. Field data from, site surveying and mapping, shallow wells, seismic profiles, and tracer tests, will characterize and facilitate modeling of the substrate and associated fluxes. This characterization and modeling will constrain the scope and methods for a follow-up study of (1) the adequacy of the platform layout of wells to measure laterally advective heat fluxes, (2) the need for additional wells to measure deeper heat fluxes and storage, (3) the need for three-dimensional seismic data acquisition and/or full tomographic analysis and waveform modeling, to determine boundary conditions.

该项目是一项基于定量的物理学研究，对大河低潮区的热预算进行了研究。 这与目前在流温度与低血流量之间的相互作用中的研究有关。 了解低风潮区域的传热对水质及其在美国西部的调节具有重要意义，并且可能是研究人员，监管机构和水处理专业人员的新工具。 初步结果表明，温暖的河水在其在砾石棒下的过境期间经历了低温冷却。 围绕低音冷却策略设计了河流的修复和污染交易方案，这使得对这种现象的充分理解是必要的。 最初的假设包括：（1）在低音区域中实际上并未在白天进行温暖的白天水，而是在白天散发出冷却，夜间水，（2）温暖的，温暖的白天水通过a的热量来显着冷却。低音区。 这些假设的初步测试将通过野外仪器以及在俄勒冈州威拉米特河的大型碎石河上的砾石棒下的水和热通量建模来实现。 该研究地点代表了最近沉积的砾石栏，该砾石栏可提供明显的冷却。来自现场测量和映射的现场数据，浅井，地震概况和示踪剂测试将表征和促进基板和相关通量的建模。 这种表征和建模将限制（1）井的平台布局的后续研究范围和方法，以测量横向对流的热通量，（2）需要其他井来测量更深的热量通量和存储，（3）需要三维地震数据采集和/或完整的构图分析和波动构造和波动范围，并确定三维地震数据采集。