Doctoral Dissertation Research: The Mechanics of Rock Glacier Creep: A New GIS Method and A Possible Response to Climate Change

博士论文研究：岩石冰川蠕变的力学：一种新的 GIS 方法和对气候变化的可能响应

• 批准号: 0140132
• 负责人: T. Nelson Caine
• 金额: $ 1.17万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-01 至 2004-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0140132&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Mechanics; Rock

Rock glaciers are considered a glacial or periglacial feature that slowly creep downslope as a result of deformation of ice that has been consolidated with angular, coarse rock. Although rock glaciers have been studied using a variety of field techniques and, more recently, with remote aerial photography analysis, much still is unknown regarding the dynamics of flow. The mechanism by which factors like micro-topography, ice content, or rock glacier form influence rock glacier behavior is unknown. Similarly, little is known of the possible existence of regional flow patterns as a result of climate change. Previous analyses have been primarily limited to the Alps in Europe. This doctoral dissertation research project will investigate the mechanics of rock glacier creep in the U.S. and Canadian Rocky Mountains, using an approach that combines analyses using high-precision temporal aerial photography and a geographic information system (GIS). The doctoral student will design a digital methodology for detecting motion of the rock glaciers to maximize the advantages of data analysis within a GIS. Rock glacier sections within a variety of different rock glacier forms will be analyzed to gain a greater comprehension of rock glacier motion. Because active rock glaciers are considered an indicator of discontinuous permafrost, a regionalized approach to rock glacier motion will be undertaken to detect climatically induced changes in permafrost distribution. The methods employed in this study will resemble those presented in earlier studies, but they will incorporate GIS-based analytic procedures. A sequence of temporal air photos for rock glaciers will be selected and scanned at a high resolution. The photos will then be enhanced, orthorectified, and co-registered to a common scale. Point-to-point methods will be conducted in a GIS to temporally track large boulders and rocks. Attribute data about the points as well as ancillary data will be included to determine the factors affecting flow. Detailed digital elevational models (DEM) will also be constructed to monitor surface slumping. Vertical and horizontal velocities will be calculated for approximately five to ten rock glaciers extending across a latitudinal transect of the Rocky Mountains for dates ranging from 1940 to the present.As development and recreation continue to increase in mountainous regions, the nature and stability of these areas is threatened. Global warming will further alter stability. An important component to the alpine geomorphic system, rock glaciers, are expected to experience substantial change. Rock glaciers may become unstable or may cause catastrophic releases of water that could damage nearby residential areas, communication towers, ski lifts, hiking paths, campgrounds, or other recreational areas. The results of this study should help monitor the form rock glaciers. They also will provide a better understanding of the dynamics of rock glacier flow, which will enhance our understanding of other rock glaciers and permafrost distribution on other terrestrial planets such as Mars. The study will develop methods using a GIS that will allow the input of ancillary data and incorporate IKONOS data for future analysis. This GIS-based format will be easily updateable and transferable to other parts of the world. As a result, this research will help advance the monitoring of global changes in permafrost. As a Doctoral Dissertation Research Improvement award, this award also will provide support to enable a promising student to establish a strong independent research career.

岩石冰川被认为是一种冰川或周围的特征，由于冰的变形已与角度的粗岩合并，因此缓慢地下坡逐渐爬行。 尽管已经使用各种现场技术对岩石冰川进行了研究，并且最近通过远程航空摄影分析，关于流动动力学仍然尚不清楚。 微观映射，冰块或冰川形式等因素影响岩石冰川行为的机制尚不清楚。 同样，由于气候变化而导致的区域流程模式可能存在很少知道。 先前的分析主要限于欧洲的阿尔卑斯山。 该博士学位论文研究项目将使用一种方法，使用一种方法结合了使用高精确的时间航空摄影和地理信息系统（GIS）结合分析的方法，研究了美国和加拿大落基山脉的岩石冰川蠕变的机制。 博士生将设计一种数字方法，用于检测岩石冰川的运动，以最大程度地提高GIS中数据分析的优势。 将分析各种不同岩石冰川形式内的岩石冰川切片，以更了解岩石冰川运动。 由于活跃的冰川被认为是不连续的多年冻土的指标，因此将采用区域化的岩石冰川运动方法，以检测到气候诱导的多年冻土分布的变化。 这项研究中采用的方法将类似于早期研究中提出的方法，但它们将结合基于GIS的分析程序。 将选择一系列用于冰川的时间空气照片，并以高分辨率进行扫描。 然后，这些照片将得到增强，矫正并共同注册到共同的尺度。 点对点方法将在GIS中进行，以在时间上跟踪大巨石和岩石。 有关点以及辅助数据的属性数据将包括在内，以确定影响流动的因素。 还将构建详细的数字高度模型（DEM）以监视表面倾斜。 将计算垂直和水平速度，以大约五到十个岩石冰川延伸，这些岩石冰川延伸到落基山脉的纬度横除山脉的横断面，以范围从1940年到现在。随着山区的发展和娱乐，这些地区的性质和稳定性继续增加，这些地区的性质和稳定性受到威胁。 全球变暖将进一步改变稳定性。 高山地貌系统的重要组成部分，岩石冰川，预计将经历重大变化。 岩石冰川可能会变得不稳定，或者可能导致灾难性的水释放，可能会损害附近的住宅区，通讯塔，滑雪缆车，远足路径，露营地或其他休闲区。 这项研究的结果应有助于监测岩石冰川的形式。 他们还将更好地了解岩石冰川流动的动力学，这将增强我们对其他岩石冰川和其他陆地行星（例如火星）上的多年冰冻分布的理解。 该研究将使用GIS开发方法，该方法将允许输入辅助数据，并将Ikonos数据纳入以后的分析。 这种基于GIS的格式将很容易更新，并且可以转移到世界其他地区。 结果，这项研究将有助于进步监测永久冻土的全球变化。 作为博士学位论文研究改进奖，该奖项还将提供支持，使有前途的学生能够建立强大的独立研究职业。