Paleomagnetism of Glacial Diamictons and Subglacially Deformed Sediment

冰川直径中的剩余磁化方向没有根据沉积时间和地点的已有地磁场记录进行测试，也没有确定作为地磁场记录器的直径的准确性。已建立的威斯康星州晚期地磁偏转记录，来自纽约莫霍克河谷西部各种沉积物中的DRM，将被用来测试同期冰川、沉积物流沉积、远洋降水直径和亚冰川变形湖层的剩磁保真度。除剩磁外，还将测量磁化率各向异性(AMS)和磁滞各向异性(AAS)。AMS将用于确定以携带粘性剩磁的粗颗粒为主的织物，而原子吸收光谱应记录以携带稳定剩磁的细颗粒为主的织物。显微组构、AMS和AAS的岩石学分析将被用来确定不同类型直径岩中的剩磁方向和颗粒取向是否与地磁场方向、质量运动、冰下剪切、脱水或压实有关。与以往的工作不同，这项研究将：1)根据已建立的地磁场记录测试剩磁方向，2)区分成因直径类型，3)利用原子吸收光谱和岩石组构分析来研究颗粒排列。

Remanent magnetization directions in glacial diamictons have not been tested against established records of the geomagnetic field at the time and place of deposition and the accuracies of diamictons as geomagnetic field recorders have not been determined. An established record of Late Wisconsinan geomagnetic declination, from DRM in varved sediment in the western Mohawk Valley, New York, will be used to test the fidelity of remanence from contemporaneous till, sediment flow deposits, pelagic rainout diamicton, and subglacially deformed lacustrine beds. In addition to remanence, anisotropy of magnetic susceptibility (AMS) and anisotropy of anhysteretic susceptibility (AAS) will be measured. AMS will be used to determine fabrics dominated by coarse particles that carry a viscous remanence, while AAS should record fabrics dominated by fine particles that carry a stable remanence. Petrographic analysis of microfabrics, AMS, and AAS will be used to determine whether remanence directions and particle alignment in various types of diamictons are related to geomagnetic field orientation, mass movement, subglacial shearing, dewatering or compaction. Unlike previous works, this study will: 1) test remanence direction against an established geomagnetic field record, 2) distinguish between genetic diamicton types, and 3) use AAS and petrofabric analysis to study grain alignment.