Geological history constraints on grounding line retreat in the Thwaites Glacier Systems

主要目标是确定冰盖在现场多个阶段推进的时间和持续时间。这名学生将使用一套独特的不稳定鹅卵石，这些鹅卵石来自教皇冰川旁边的努纳塔克，它们的大小和岩性差异很大，尽管所有的鹅卵石都沉积在相同的海拔高度，但它们的风化特征也不同。这名学生将应用使用多种宇宙成因核素的暴露年龄测定技术，此外，还将利用约翰逊和罗伯茨主管在实地考察期间对反常地貌背景进行的有充分记录的观察。BAS的档案馆保存着这套产品中的22个样品。学生首先将致力于识别不同的岩性和风化特征，然后选择样本的子集进行宇宙成因分析。纯石英和用于10Be AMS测量的靶材(如果需要，还可以准备26Al)将由学生在伦敦帝国理工学院鲁德主管的实验室进行。然后，他们将选择多达10个样本进行原位宇宙14C测量，以确定冰盖在该地点重新推进的持续时间和时间。第二个目标是使用遥感(世界景观2号和3号卫星图像，加上主管罗伯茨获得的无人机图像)来探测教皇冰川附近的努纳塔克上冰川不稳定的地区。菲利帕·梅森(帝国)将监督该项目的这一部分。在实地活动之前使用遥感有可能使地表暴露年代测定更有效地取样，从而节省与南极偏远实地工作有关的时间和费用。

The primary objective is to determine the timing and duration of multiple phases of ice sheet advance over the site. The student will work with a unique suite of erratic cobbles from a nunatak next to Pope Glacier that are of widely varying size and lithology, as well as having differing weathering characteristics despite all having been deposited at the same elevation. The student will apply the technique of exposure age dating using multiple cosmogenic nuclides, in addition to drawing on the well-documented observations of geomorphological context of the erratics made during a field campaign by supervisors Johnson and Roberts. 22 samples from this suite are held in the archive at BAS. The student will initially work on identifying their different lithological and weathering characteristics before choosing a subset of samples for cosmogenic analysis. Preparation of pure quartz and targets for 10Be AMS measurement (and 26Al if required) will be undertaken by the student in supervisor Rood's laboratory at Imperial College London. They will then select up to 10 samples for in situ cosmogenic 14C measurement, to determine the duration and timing of ice sheet re-advances over the site.A secondary objective is to use remote sensing (World View 2 and 3 satellite imagery, plus drone imagery obtained by supervisor Roberts) to detect areas where glacial erratics are common on nunataks near Pope Glacier. Philippa Mason (Imperial) will supervise this part of the project. Using remote sensing in advance of field campaigns has the potential to enable more efficient sampling for surface exposure dating and thus save time and expenses associated with remote Antarctic fieldwork.