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Engineering of glacial soils
Published in Barry G. Clarke, Engineering of Glacial Deposits, 2017
A topographical survey is of immense value in areas subject to glaciation because it may provide a view of historical land forms, particularly in rural areas where there may be limited anthropogenic alteration of the ground surface. Landforms can be an indicator of types of glacial soils though the last glacial deposit may be overlain by made ground or post-glacial deposits masking the profile immediately following the end of the last glacial period, or altered by the formation of the current drainage system or by ground movements following isostatic uplift. Linear infrastructure projects may cross several landforms suggesting a variation in glacial soils, whereas a development project may be the site of a single landform. Hence, the scale of a landform and its relation to a project footprint are relevant. In the latter case, a study should be undertaken to determine the regional landforms.
The Earth Through Time
Published in Aurèle Parriaux, Geology, 2018
These cold periods were interrupted by warmer episodes (interglacial periods) during which large glaciers rapidly disappeared. The last glacial period (the Würm) ended only about 14,000 years ago in the Alps. Whereas the present site of the Federal Institute of Technology Lausanne was still covered by 700 m of ice 18,000 years ago (Fig. 3.26), the Rhone glacier retreated from Solothurn to its present location in about three thousand years.
The Earth in Time
Published in Aurèle Parriaux, Geology, 2018
These cold periods were interrupted by warmer episodes (interglacial periods) during which the large glaciers rapidly disappeared. The last glacial period (the Würm) ended only about 14,000 years ago in the Alps. When the present site of the Federal Institute of Technology Lausanne was still covered by 700 m of ice 18,000 years ago (Fig. 3.26), the Rhone glacier retreated from Solothurn to its present location in three thousand years.
The geological process for gas hydrate formation in the Qilian Mountain permafrost
Published in Petroleum Science and Technology, 2019
Zhengquan Lu, Gangyi Zhai, Yinhui Zuo, Quanfeng Wang, Dongwen Fan, Shiqi Tang, Daodong Hu, Hui Liu, Ting Wang, Youhai Zhu, Rui Xiao
The uplift of the Qinghai-Tibet Plateau and the process of glaciations or permafrost formation are correlated. According to the research (Qi et al. 2014), the glacial drifts and the glacial alluvium deposits were found around the lake of Qinghai. These glacial drifts and the glacial alluvium deposits were formed during the last third glacial period or the maximal glacial period at the age of 0.5–0.7 Ma, the last second glacial period at the age of 130–300 Ka and the last glacial period at the age of 10–70 Ka, respectively. An evolutionary sequence was then preliminarily established during the quaternary glacial period and interglacial period in the region of the Qilian Mountain. Additionally, the palaeo-temperature and the palaeo-environment was also rebuilt during the quaternary glacial period and interglacial period in the region of the Qilian Mountain. Results showed that the permafrost formed in the region of the Qilian Mountain no later than the early Middle Pleistocene. Hence it is indirectly inferred that the gas hydrate formation time should be no later than the early Mid-Pleistocene in the Qilian Mountain.
The Basilicata region (Southern Italy): a natural and ‘human-built’ open-air laboratory for manifold studies. Research trends over the last 24 years (1994–2017)
Published in Geomatics, Natural Hazards and Risk, 2019
Fabrizio Terenzio Gizzi, Monica Proto, Maria Rosaria Potenza
The CLT green cluster is mainly related to the paleoclimate studies performed on Monticchio lake records. The researchers identified environmental and climatic changes during the last glacial period, including the Dansgaard-Oeschger and Heinrich event(s) [6]. This was possible by the use of high-resolution sedimentological, microstratigraphical, geochemical, physical, radiocarbon, pollen, diatom, and plant macrofossil analyses performed on a large number of core samples of the lacustrine sequence (e.g. Watts et al. 1996a, 1996b; Zolitschka and Negendank 1996; Hajdas et al. 1997; Allen et al. 1999; Bindi et al. 1999; Huntley et al. 1999; Nimmergut et al. 1999; Ramrath et al. 1999; Allen et al. 2000). Also the use of geomagnetic records were considered as proxies of climate change until about 100 kyr BP (e.g. Creer and Morris 1996; Brandt et al. 1999).