Climatic and tectonic controls on sedimentation within glaciated basins

气候和构造对冰川盆地内沉积的控制

• 批准号: 140271-2012
• 负责人: Eyles, Carolyn
• 金额: $ 1.97万
• 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: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=507662
• 关键词: Climatic; tectonic; controls; sedimentation; within

Episodes of extreme climate change resulting in glacial conditions have affected our planet for almost 3 billion years. The infill of sedimentary basins affected by these past glacial events contains an extremely valuable record of past climatic conditions in addition to tectonic events related to basin evolution. Unfortunately, discriminating the geologic signature of climatic and tectonic controls on sedimentation is difficult and often compromises the accuracy of paleoenvironmental reconstructions. Interpretation of coarse-grained facies types containing deformation structures is particularly challenging as these features may result from glacial processes, subglacial overriding, scouring by icebergs, or seismic shock, and each of these processes has very different paleoenvironmental significance. The objective of the proposed research is to identify sedimentological criteria that can be used to discriminate climatic and tectonic influences on sedimentation in glaciated basins in order to enhance paleoenvironmental analysis and understanding of potential resource distribution. The proposed research will involve field investigation and analysis of sediments within glaciated basins of different ages and tectonic setting. Late Cenozoic glaciomarine sediments of the Yakataga Fm. on Middleton Island, Alaska have accumulated in a tectonically active collisional margin setting over the past 6 million years and contain a long and continuous record of Late Cenozoic glaciation and tectonic activity. The Late Paleozoic Lower Parmeener Supergroup of the Tasmania Basin contains diamictites and fossiliferous siltstones that record the prolonged deglaciation of southern Gondwana under an extensional tectonic regime. Late Quaternary deposits of glacial, lacustrine and fluvial origin have accumulated under glacial and interglacial conditions in the Lake Ontario basin and provide valuable data with which to compare the pre-Quaternary basin infills. This research is not only important for Paleozoic and Quaternary paleoenvironmental analysis but is also valuable for groundwater management at both local and national levels, and provides many opportunities for the training of HQP.

极端气候变化导致的冰川条件已经影响了我们的星球近30亿年。受这些过去冰川事件影响的沉积盆地填充物，除了与盆地演化有关的构造事件外，还包含了对过去气候条件的极有价值的记录。不幸的是，判别气候和构造对沉积控制的地质特征是困难的，而且往往会损害古环境重建的准确性。含变形构造的粗粒相类型的解释尤其具有挑战性，因为这些特征可能是由冰川作用、冰下覆盖、冰山冲刷或地震冲击造成的，每种过程都具有非常不同的古环境意义。本研究的目的是确定可用于区分冰川盆地气候和构造对沉积影响的沉积学标准，以加强古环境分析和对潜在资源分布的认识。拟进行的研究将包括对不同时代和构造背景的冰川盆地内沉积物的实地调查和分析。Yakataga组晚新生代冰川期海洋沉积物。在过去的600万年里，阿拉斯加米德尔顿岛积聚在一个构造活跃的碰撞边缘环境中，并包含了晚新生代冰川作用和构造活动的长期连续记录。塔斯马尼亚盆地晚古生代下Parmeener超群含有二晶岩和化石粉砂岩，记录了伸展构造下冈瓦纳南部的长时间脱冰作用。安大略湖盆地在冰期和间冰期条件下积累了晚第四纪冰川、湖泊和河流沉积，为比较前第四纪盆地充填提供了有价值的数据。该研究不仅对古生代和第四纪古环境分析具有重要意义，而且对地方和国家层面的地下水管理具有重要价值，并为HQP的培训提供了许多机会。