Monitoring the thermal state of permafrost by automated time-lapse capacitive resistivity imaging

通过自动延时电容电阻率成像监测永久冻土的热状态

• 批准号: NE/I000917/1
• 负责人: Oliver Kuras
• 金额: $ 16.06万
• 依托单位: British Geological Survey
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2010
• 资助国家: 英国
• 起止时间: 2010 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FI000917%2F1
• 关键词: Monitoring; thermal; state; permafrost; automated

Long-term monitoring of subsurface processes increasingly relies on intelligent, systematic data collection by innovative field sensors. The aim of the proposed project is to develop a new technology concept for the non-invasive volumetric imaging and routine temporal monitoring of the thermal state of permafrost. Permafrost has been identified as one of six cryospheric indicators of global climate change within the monitoring framework of the World Meteorological Organization (WMO) Global Climate Observing System (GCOS). Changes in permafrost temperature, associated with the freezing or thawing of pore water, result in significant changes in electrical resistivity. Non-invasive assessment and volumetric monitoring of resistivity changes are facilitated by 4D Electrical Resistivity Tomography (ERT). Tomographic reconstruction with appropriate spatial and temporal resolution enables intuitive visualisation and opens up the important opportunity for quantitative analysis of freeze and thaw processes, including the calibration to permafrost temperature. However, despite the broad appeal of conventional ERT methodology, electrical sensors require galvanic coupling with the ground. In permafrost regions, metal electrodes must be physically implanted into the active layer, which is subject to seasonal freezing and thawing. This can lead to significant practical limitations on field measurements due to high levels of and large variations in contact resistances between sensors and the host bedrock, soil or building material as it freezes and thaws. Using a novel capacitively-coupled ERT approach, we propose to demonstrate the technical feasibility of undertaking time-lapse tomographic measurements using permanent, in-situ capacitive sensors to remotely monitor the thermal state of permafrost. This will lead to significant improvements in monitoring capability, both for permafrost simulation experiments in the laboratory and for practical applications in the field. The work will include numerical simulation to determine optimal distributed capacitive sensor networks required for volumetric imaging and long-term monitoring of permafrost, both at the field and at the laboratory scale. Based on the results, a measurement system for multi-sensor automated time-lapse data acquisition will be designed and a viable architecture for a laboratory prototype system will be established. Subsequently, a functional benchtop prototype will be developed and technical feasibility of multi-sensor data acquisition and automated operation will be demonstrated. Finally, we will validate the concept of making automated time-lapse temperature-calibrated CRI measurements in controlled laboratory experiments that simulate permafrost growth, persistence and thaw in bedrock.

地下过程的长期监测越来越依赖于创新的现场传感器进行智能、系统的数据收集。拟议项目的目的是开发一种新的技术概念，用于永久冻土热状态的非侵入性体积成像和常规时间监测。在世界气象组织（气象组织）全球气候观测系统（气候观测系统）的监测框架内，多年冻土被确定为全球气候变化的六个冰冻圈指标之一。多年冻土温度的变化，与孔隙水的冻结或融化，导致电阻率的显着变化。电阻率变化的非侵入性评估和体积监测由4D电阻率断层扫描（ERT）促进。具有适当的空间和时间分辨率的层析重建能够实现直观的可视化，并为定量分析冻融过程（包括冻土温度的校准）提供了重要的机会。然而，尽管传统的ERT方法具有广泛的吸引力，但电传感器需要与地面的电流耦合。在永久冻土区，金属电极必须物理植入到活性层中，活性层会受到季节性冻结和融化的影响。由于传感器与宿主基岩、土壤或建筑材料之间的接触电阻在冻结和解冻时水平高且变化大，这可能导致对现场测量的显著实际限制。使用一种新的电容耦合ERT方法，我们建议证明进行延时层析成像测量的技术可行性，使用永久性的，原位电容传感器远程监测冻土的热状态。这将导致监测能力的显着改善，无论是在实验室中的永久冻土模拟实验，并在现场的实际应用。这项工作将包括数值模拟，以确定体积成像和长期监测冻土所需的最佳分布式电容传感器网络，无论是在现场还是在实验室规模。基于这些结果，将设计一个多传感器自动延时数据采集的测量系统，并将建立一个可行的实验室原型系统架构。随后，将开发一个功能台式原型，并展示多传感器数据采集和自动化操作的技术可行性。最后，我们将验证的概念，使自动延时温度校准CRI测量在受控的实验室实验，模拟永久冻土生长，持久性和基岩解冻。

项目成果

Encyclopedia of Solid Earth Geophysics

• DOI: 10.1007/978-3-030-10475-7
• 发表时间: 2020
• 期刊: Encyclopedia of Earth Sciences Series
• 作者: D. James

The use of capacitive resistivity imaging (CRI) for monitoring laboratory experiments simulating permafrost growth, persistence and thaw in bedrock

使用电容电阻率成像 (CRI) 监测模拟基岩中永久冻土生长、持久性和融化的实验室实验

• 发表时间: 2012
• 期刊: AGU Fall Meeting Abstracts
• 作者: Kuras O.

Monitoring rock freezing and thawing by novel geoelectrical and acoustic techniques

• DOI: 10.1002/2016jf003948
• 发表时间: 2016-12
• 期刊: Journal of Geophysical Research: Earth Surface
• 作者: J. Murton;O. Kuras;M. Krautblatter;T. Cane;D. Tschofen;S. Uhlemann;Sandra Schober;P. Watson

Recent developments in the direct-current geoelectrical imaging method

• DOI: 10.1016/j.jappgeo.2013.02.017
• 发表时间: 2013-08-01
• 期刊: JOURNAL OF APPLIED GEOPHYSICS
• 影响因子: 2
• 作者: Loke, M. H.;Chambers, J. E.;Wilkinson, P. B.
• 通讯作者: Wilkinson, P. B.

Long-term geoelectrical monitoring of laboratory freeze-thaw experiments on bedrock samples

基岩样品实验室冻融实验的长期地电监测

• 发表时间: 2014
• 期刊: EGU General Assembly Conference Abstracts
• 作者: Kuras Oliver