Collaborative Research: Late Quaternary Glaciations of Northern Novaya Zemlya, Russia

合作研究：俄罗斯新地岛北部的晚第四纪冰川作用

• 批准号: 9529293
• 负责人: Steven Forman
• 金额: --
• 依托单位: Ohio State University Research Foundation -DO NOT USE
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-07-15 至 1997-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9529293&HistoricalAwards=false
• 关键词: Collaborative; Research; Late; Quaternary; Glaciations

The extent and timing of Pleistocene ice sheets over northern Eurasia remain unresolved. The views range from full coverage of the Barents and Kara Seas by a marine-based ice sheet to land-based ice-cap systems on adjacent archipelagos. The heart of the divergence on the nature of last glaciation in northern Eurasian is uncertainty on ice sheet thickness over Novaya Zemlya and extension into Siberia. In collaboration with the Murmansk Institute of Marine Biology we propose to initiate basic glacial-geologic, stratigraphic and geochronologic studies to provide new field data to independently evaluate the limits and timing of Weichselian glacial and deglacial events on Novaya Zemlya, Russia. Field research will focus on three field areas on northern Novaya Zemlya, where ice-free forelands contain abundant raised marine and glacial features. We plan to use the following approaches to decipher the record of Quaternary glaciations on Novaya Zemlya: 1) High resolution (10-m pixels) SPOT satellite imagery will be used to evaluate large scale sea-level, glacial erosional and depositional features (moraines) that may not readily be discernible in the field. 2) Documentation of the timing and rate of the glacial-isostatic response by radiocarbon dating of subfossils included in raised beaches of known elevation. 3) A study of the stratigraphy and sedimentology of superimposed Quaternary sediments in cliff sections. Particular attention will be given to the recognition of glacial damicts and unconformities, and the collection of micro-and macro-fauna for paleoenvironmental assessment and chronologice control. Provenance studies of clasts from glacial diamicts and fabric analysis should provide new information on glacial source area. 4) Age control for the latest glacial/sea level events will be derived from conventional and AMS radiocarbon dating of included marine subfossil and driftage. The number and timing of older events will be constrained by amino acid epimerization analyses of mollusks using L-isoleucine/D-alloisoleucine ratios and higher resolution D/L aspartic acid ratios. Numeric age will be determined by luminescence geochronometry on the fine-grained fraction (4-11(m) from raised sublittoral sediments. 5) Integration of field data with isostatic and glaciological modeling to provide insight into glacier thickness, position of ice divides, domes and streams and response to sea level rise. Results from this study are important for evaluating if ice sheets on northern continental shelves responded synchronously, if the Barents, Kara and Norwegian Seas deglaciated prior to 14 ka ago, and the effect of Eurasian ice sheets on North Atlantic thermohaline circulation. This field-based research will provide new data on Weichselian glacier geometry in the Russian Arctic, where little currently exists, which is a critical boundary condition for evolving global climate models.

欧亚大陆北部更新世冰盖的范围和时间仍未解决。 视野范围从海洋冰盖完全覆盖巴伦支海和喀拉海到邻近群岛的陆基冰盖系统。 关于欧亚北部末次冰期性质的分歧的核心是新地岛冰盖厚度和西伯利亚延伸的不确定性。 我们建议与摩尔曼斯克海洋生物学研究所合作，启动基础的冰川地质、地层学和地质年代学研究，以提供新的现场数据，以独立评估俄罗斯新地岛Weichselian冰川和冰消事件的限制和时间。 实地研究将集中在新地岛北部的三个野外区域，那里无冰的前陆拥有丰富的凸起海洋和冰川特征。 我们计划采用以下方法破译新地岛第四纪冰川作用的记录： 1）高分辨率（10米像素）SPOT卫星图像将用于评估大尺度海平面、冰川侵蚀和沉积特征（冰碛）这在现场可能不容易辨别。 2) 通过对已知海拔的凸起海滩中的亚化石进行放射性碳测年，记录冰川均衡响应的时间和速率。 3）悬崖断面第四纪叠置沉积地层学和沉积学研究。 将特别关注冰川坝和不整合面的识别，以及用于古环境评估和年代控制的微型和大型动物群的收集。 冰川杂岩碎屑的来源研究和结构分析应该为冰川源区提供新的信息。 4) 最新冰川/海平面事件的年龄控制将源自对所含海洋亚化石和漂流物进行的常规和 AMS 放射性碳测年。 较旧事件的数量和时间将受到使用 L-异亮氨酸/D-别异亮氨酸比率和更高分辨率的 D/L 天冬氨酸比率对软体动物进行氨基酸差向异构分析的限制。 数字年龄将通过细粒部分（来自凸起的滨海沉积物的 4-11(m)）的发光地球测时法确定。5) 将现场数据与均衡和冰川模型相结合，以深入了解冰川厚度、冰缝位置、穹顶和溪流以及对海平面上升的反应。 这项研究的结果对于评估北部大陆架冰盖是否同步响应、巴伦支海、喀拉海和挪威海是否在 14 年前之前消融以及欧亚冰盖对北大西洋温盐环流的影响具有重要意义。 这项基于实地的研究将提供有关俄罗斯北极地区韦克瑟利安冰川几何形状的新数据，该地区目前几乎不存在，这是不断发展的全球气候模型的关键边界条件。