Deciphering the depositional history of glaciated basins using sedimentology and geomatics

利用沉积学和测绘学破译冰川盆地的沉积历史

• 批准号: 140271-2006
• 负责人: Eyles, Carolyn
• 金额: $ 1.84万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=363149
• 关键词: Deciphering; depositional; history; glaciated; basins

Many urban areas in Canada and northern North America are underlain by thick (up to 200 m) successions of Quaternary-age sediment deposited under glacial and interglacial conditions.  These sediments form a rich source of information regarding environmental and climatic conditions that existed in the region over the past 120,000 years.  However, there is much debate regarding the origin of many of these sediments.  Some researchers believe that the late Quaternary record was formed by 'catastrophic' subglacial megafloods while others believe it formed through 'normal' subglacial processes operating over extended periods of time.  There is also vigorous debate regarding the severity of climatic conditions during past 'glacial' episodes and the extent of glacial lakes in the Great lakes basins.  Understanding the environmental conditions under which the Quaternary sediments formed is essential for accurate reconstruction of past climatic change and also for prediction of subsurface water and contaminant movement in aquifers found within these deposits. This proposal is for funding to examine the depositional origin of Quaternary-age sediments in the Great Lakes basins using both 'traditional' sedimentological techniques and newly developed 'geomatics' approaches that involve computer-based spatial analysis of digital databases.  Subsurface geological databases will be created for selected areas using information obtained from waterwell records, construction reports and natural exposures.  These data will be visualized as 3-D subsurface models and analyzed using GIS software. This will provide valuable information on which the depositional origin of the Quaternary deposits can be determined and will allow identification of the location and form of subsurface aquifers, important information for groundwater resource exploration, protection and remediation issues. The novelty and significance of the proposed research lies in the use of a 'hybrid' approach, combining traditional sedimentological methods of analysis with newly developed techniques for the spatial analysis of large digital databases.  This type of hybrid analysis is used in the oil and gas industry and can now be applied to investigations of Quaternary sediment stratigraphies.

加拿大和北美北方的许多城市地区都被厚厚的在冰川和间冰期条件下沉积下来的一系列第四纪沉积物（高达200米）。这些沉积物构成了有关该地区过去12万年来环境和气候条件的丰富信息来源。然而，关于这些沉积物的起源有很多争论。一些研究人员认为，晚第四纪的记录是由“灾难性的”冰下大洪水形成的，而另一些人则认为它是通过“正常的"冰下过程在很长一段时间内运作形成的。关于过去“冰期”时期气候条件的严重性和五大湖盆地冰湖的范围的激烈争论。了解第四纪沉积物形成的环境条件对于准确重建过去的气候变化以及预测这些沉积物中地下水和含水层中污染物的运动是必不可少的。这项建议是为了提供资金，利用“传统”沉积学技术和新开发的“地理信息学”方法，包括对数字数据库进行基于计算机的空间分析，研究五大湖盆地中百年沉积物的沉积起源。这些数据将被可视化为三维地下模型，并使用GIS软件进行分析。这将提供有价值的信息，根据这些信息可以确定第四纪沉积物的沉积起源，并可以确定地下含水层的位置和形式，这是地下水资源勘探、保护和补救问题的重要信息。该研究的新奇和重要性在于采用了一种“混合”方法，将传统的沉积学分析方法与新开发的大型数字数据库空间分析技术相结合，这种混合分析方法用于石油和天然气工业，现在可以应用于第四纪沉积地层的调查。