Geotechnical and sediment physical characterization of glacial-interglacial cycles on a late Miocene to Holocene shelf-slope transect (Canterbury Basin, New Zealand)

这项建议是为对IODP 317(坎特伯雷盆地，新西兰)考察期间获得的样品进行巡航后分析和数据集处理而设计的。探险317旨在了解全球海平面变化与当地构造和沉积过程在控制大陆边缘沉积旋回方面的相对重要性。从高频层序地层学的角度，对晚中新世-现代陆架坡剖面的4个钻井现场的19个区域层序界面不整合进行了研究。首先，船上的结果表明，对不整合的解释是有问题的，因为由间歇和/或钻井过程引起的缺失层段的厚度是未知的。对于进一步的研究，如年龄深度估算、岩性层序对比、二维反剥离等，获取这些信息是至关重要的。一种幸运的方法是，在通过土工测量(固结仪和沉积物强度试验)确定压实和降水特性的基础上，重建“缺失的地层”，这些样品来自不整合上方和下方的56个全面样品。第二个目标是回答沉积物压实历史是否可以在陆架斜坡断面上水平追踪，垂直追踪到沉积物深度超过980m的问题。这一结果以及对物性、井下测井和沉淀学船上资料的补充分析将支持坎特伯雷盆地沉陷和海平面变化的定量分析。

This proposal is designed for postcruise analyses of samples and processing of data sets gained during IODP Expedition 317 (Canterbury Basin, New Zealand). Expedition 317 was aimed to understand the relative importance of global sea level changes versus local tectonic and sedimentary processes in controlling continental margin sedimentary cycles. Nineteen regional sequence-bounding unconformities, know from high-frequency sequence stratigraphy, were investigated on four drill sites of a late Miocene to recent continental shelfslope transect. First onboard results show that the interpretation of the unconformities is problematical because the thicknesses of the missing intervals, caused by hiatuses and/or the drilling process, are unknown. For further investigations, e.g. age-depth estimation, lithological sequence correlation, two dimensional backstripping, it is crucial to get these information. An auspicious approach is the reconstruct of the “missing strata” on the basis of the determination of compaction and dewatering properties via geotechnical measurements (oedometer and sediment strength tests) on 56 whole-round samples from areas above and below the unconformities. A second goal is to respond to the question if the sediment compaction history can be traced horizontally across a shelf-slope transect and vertically down to a sediment depth of more than 980 m. The results and additional analyses of physical property, down-hole logging and sedimentological shipboard data will support the quantitative analysis of subsidence and sea level change in Canterbury Basin.