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991.
Christos Katrantsiotis Martin Dahl Veronica Palm Johan Rönnby Thomas Andrén Elinor Andrén 《Boreas: An International Journal of Quaternary Research》2023,52(2):206-222
We reconstruct the Holocene shore displacement of the Västervik-Gamlebyviken area on the southeast coast of Sweden, characterised by a maritime cultural landscape and archaeological significance since the Mesolithic. Sediment cores were retrieved from four lake basins that have been raised above sea level due to the postglacial land uplift and eustatic sea level changes after the melting of the Fennoscandian Ice Sheet. The cores were radiocarbon dated and analysed for loss on ignition and diatoms. The isolation thresholds of the basins were determined using LiDAR data. The results provide evidence for the initiation of the first Littorina Sea transgression in this area at 8.5 thousand calibrated years before present (cal. ka BP). A relative sea level rise by ∼7 m a.s.l. is recorded between 8.0 and 7.5 cal. ka BP with a highstand at ∼22 m a.s.l. between 7.5 and 6.2 cal. ka BP. These phases coincide with the second and third Littorina Sea transgressions, respectively, in the Blekinge area, southern Sweden and are consistent with the final deglaciation of North America. After 6.2 cal. ka BP, the relative sea level dropped below 22 m a.s.l., and remained at ∼20 m a.s.l. until 4.6 cal. ka BP coinciding with the fourth Littorina Sea transgression in Blekinge. From 4.6 to 4.2 cal. ka BP, the shore displacement shows a regression rate of 10 mm a−1 followed by a slowdown with a mean value of 4.6 mm a−1 until 1.6 cal. ka BP, when the relative sea level dropped below 3.3 m a.s.l. The Middle to Late Holocene highstand and other periods of minor sea level transgressions and/or higher salinity between 6.2 and 1.7 cal. ka BP are attributed to a combination of warmer climate and higher inflow of saline waters in the southern Baltic Sea due to stronger westerlies, caused by variations in the North Atlantic atmospheric patterns. 相似文献
992.
Surveys in Geophysics - Deception Island is an active volcano located in the South Shetland Islands, Antarctica. Although the last eruptions occurred in 1967-1970, the volcano has undergone periods... 相似文献
993.
Bachoc François Durrande Nicolas Rullière Didier Chevalier Clément 《Mathematical Geosciences》2022,54(5):941-977
Mathematical Geosciences - Kriging is a widely employed technique across computer experiments, machine learning and geostatistics. An important challenge for kriging is its high costs when dealing... 相似文献
994.
Acta Geotechnica - Hydrophobized sands have been suggested as materials for hydraulic barriers in infrastructure. When placed at the interface ground–atmosphere, environmental factors such as... 相似文献
995.
江西城门山铜矿床通过开展深边部找矿勘查,发现其探明的伴生稀散金属资源量达到大型甚至超大型规模,其中碲、铊、镉、硒等稀散金属已综合回收利用,但研究程度还很低。本文收集整理城门山矿床的编录及化验资料,总结该矿床稀散金属的矿化特征和空间分布规律,并探讨稀散金属富集机理和控制因素。结果表明,城门山矿床的稀散元素多倾向于富集在似层状硫化物型矿石中,赋存状态以独立稀散金属矿物和赋存于黄铁矿、黄铜矿和闪锌矿等硫化物晶格为主,具有随金属硫化物总量变化而变化的空间分带特征。矿石中的w(Cd)与w(Zn)具明显的正相关性(R^(2)=0.65),其他稀散元素的含量与Cu多呈弱正相关性。本文提出碲与铊与似层状硫化物矿石密切相关,镉的超常富集主要与锌的成矿作用有关,它们在热液流体萃取、运移、沉淀过程中元素分离相对较少,岩浆结晶分异导致热液流体中铟含量降低,铼主要赋存在辉钼矿中,与幔源物质参与密切相关。同时,还建立了城门山含稀散金属铜矿床的成矿模式。 相似文献
996.
Ferreira Breno S. Almeida Marcio S. S. Lopes Francisco R. Reis Cavalcanti Maria do Carmo Pires Filho Celso José 《Geotechnical and Geological Engineering》2022,40(4):1973-1987
Geotechnical and Geological Engineering - The Manso Dam, in the Brazilian State of Mato Grosso, intended for flood control and electricity generation, was built by a state-owned energy company in... 相似文献
997.
de Rezende Igor Marasini Prietto Pedro Domingos Marques Thomé Antônio Dalla Rosa Francisco 《Geotechnical and Geological Engineering》2022,40(4):1997-2008
Geotechnical and Geological Engineering - New sustainable ground improvement techniques have been recently required for applications in onshore and offshore geotechnical structures. The... 相似文献
998.
Lago Larissa Neves Casagrande Michéle Dal Toé da Conceição Ribeiro Roberto Carlos de Albuquerque e Silva Ben-Hur 《Geotechnical and Geological Engineering》2022,40(3):1585-1595
Geotechnical and Geological Engineering - The aggregates consist approximately 85% of the total volume in asphalts pavements, and their properties influence directly their behavior. Therefore, it... 相似文献
999.
Li Yang Ren Yuqi Liu Yikun Wang Nan Lei Xinghai 《Geotechnical and Geological Engineering》2022,40(9):4345-4356
Geotechnical and Geological Engineering - In view of the phenomenon that upright triangular zone and inverted triangular zone of the collapsed roof appeared alternately in the gob, a mechanical... 相似文献
1000.