Stratigraphy, Extent, and Paleoclimatic Implications of Middle Pleistocene Glacial/Interglacial Conditions, Coastal NW Alaska

阿拉斯加西部许多地方暴露出的互层冰川期和海洋沉积物构成了最著名的晚新生代区域气候变化和海平面波动的北极记录。阿拉斯加西部是北美北极地区为数不多的陆地和海洋记录都可以清楚地解决的地区之一。根据过去两年完成的区域地层学工作，现在已经知道，大约50万年前整个阿拉斯加西部的冰川期比随后的任何冰川期都要广泛一个数量级。该奖项支持对代表间冰期/冰期过渡的地层、沉积学和沉积物古生态学的研究，以更好地了解北美西北部最后一次早更新世至中期广泛冰川事件的区域气候环境。研究了近岸前三角洲沉积的海洋微、宏观化石和陆生花粉、甲虫和植物宏观化石，重建了这一过渡时期的陆海气候条件。该项目收集的数据将为了解区域古气候条件提供代理数据，对评估古雪线、白令海峡气候梯度以及气候过渡时期古地理的变化具有重要意义。

The interbedded glaciogenic and marine sediments exposed in many places along western Alaska comprise the best-known Arctic record of late-Cenozoic regional climatic change and eustatic sea-level fluctuations. Western Alaska is one of few areas in Arctic North America where both terrestrial and oceanic records can be clearly resolved. Based upon regional stratigraphic work completed over the last two years, it is now known that glaciation about 500,000 years ago throughout western Alaska was an order of magnitude more extensive than any subsequent glaciation. This award supports an investigation of the well exposed stratigraphy sedimentology, and paleoecology of sediments representing this interglacial/glacial transition to better understand the regional climatic setting that culminated in the last extensive early to middle Pleistocence glacial events in northwestern North America. Marine micro and macrofossils and terrestrial pollen, beetles, and plant macrofossils collected from nearshore prodeltaic deposits will be examined to reconstruct land-sea climatic conditions during this transitional period. Data collected from this project will provide proxy data for understanding regional paleoclimatic conditions with implications for evaluating paleosnowlines, climatic gradients through the Bering Strait, and changing paleogeography at a time of climatic transition.