LGM Late Pleistocene to Holocene Glacial History of West Antarctica

该奖项由极地方案办公室南极地质和地球物理方案提供，用于支持对西南极和南极半岛大陆架冰晶地质的研究。据推测，南极半岛地区的不同冰川系统对气候变化和海平面上升的反应比西南极或东南极冰盖更快。这主要是由于这些冰块的规模较小，以及半岛所处的纬度较高。事实上，南极半岛的冰架目前正以每年高达一公里的速度后退。但这些变化是由于该地区最近的大气变暖造成的，还是仅仅是自上一次冰川盛期以来的最后一个退缩阶段？这个项目假设，南极半岛地区的退冰史相当复杂，不同的冰川系统退缩的速度和时间不同。这一复杂的退缩历史反映了该区域冰川系统的不同大小以及不同的气候和地理环境。需要了解南极半岛冰川系统的晚更新世至全新世冰川历史，以解决这些冰川系统在这段时间内如何应对海平面和气候变化的问题。这项调查从大陆架获取了新的海洋地质和地球物理数据，以确定不同的冰川系统是否以及何时在大陆架上搁浅，确定搁浅冰的范围，并审查冰川退缩的历史。该项目将建立在广泛的地震数据集和数以百计的沉积岩心的基础上，这些数据是在早些时候(1980年代S)的航海中沿半岛收集的。这项调查的关键是从主要排水口获取条带水深测量、侧扫声纳和极高分辨率海底(Chirp)剖面。这些新数据将为重建南极半岛冰川记录提供必要的地貌和地层框架。预期的结果将有助于限制未来冰川和冰盖活动的模型。

9909734AndersonThis award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports research on the glaciomarine geology of the continental shelves of West Antarctica and the Antarctic Peninsula. It is hypothesized that the different glacial systems of the Antarctic Peninsula region have been more responsive to climate change and sea-level rise than either the West Antarctic or East Antarctic ice sheets. This is due mainly to the smaller size of these ice masses and the higher latitude location of the peninsula. Indeed, ice shelves of the Antarctic Peninsula are currently retreating at rates of up to a kilometer per year. But are these changes due to recent atmospheric warming in the region or are they simply the final phase of retreat since the last glacial maximum?This project hypothesizes that the deglacial history of the Antarctic Peninsula region has been quite complex, with different glacial systems retreating at different rates and at different times. This complex recessional history reflects the different sizes as well as different climatic and physiographic settings of glacial systems in the region. An understanding of the Late Pleistocene to Holocene glacial history of the Antarctic Peninsula glacial systems is needed to address how these systems responded to sea-level and climate change during that time interval. This investigation acquire new marine geological and geophysical data from the continental shelf to determine if and when different glacial systems were grounded on the shelf, to establish the extent of grounded ice, and to examine the history of glacial retreat. The project will build on an extensive seismic data set and hundreds of sediment cores collected along the Peninsula during earlier (1980's) cruises. Key to this investigation is the acquisition of swath bathymetry, side-scan sonar and very high-resolution sub-bottom (chirp) profiles from key drainage outlets. These new data will provide the necessary geomorphologic and stratigraphic framework for reconstructing the Antarctic Peninsula glacial record. Anticipated results will help constrain models for future glacier and ice sheet activity.