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Alar Rosentau Merle Muru Aivar Kriiska Dmitry A. Subetto Jüri Vassiljev Tiit Hang Dmitry Gerasimov Kerkko Nordqvist Anna Ludikova Lembi Lõugas Hanna Raig Kersti Kihno Raivo Aunap Nikolay Letyka 《Boreas: An International Journal of Quaternary Research》2013,42(4):912-931
Based on geological and archaeological proxies from NW Russia and NE Estonia and on GIS‐based modelling, shore displacement during the Stone Age in the Narva‐Luga Klint Bay area in the eastern Gulf of Finland was reconstructed. The reconstructed shore displacement curve displays three regressive phases in the Baltic Sea history, interrupted by the rapid Ancylus Lake and Litorina Sea transgressions c. 10.9–10.2 cal. ka BP and c. 8.5–7.3 cal. ka BP, respectively. During the Ancylus transgression the lake level rose 9 m at an average rate of about 13 mm per year, while during the Litorina transgression the sea level rose 8 m at an average rate of about 7 mm per year. The results show that the highest shoreline of Ancylus Lake at an altitude of 8–17 m a.s.l. was formed c. 10.2 cal. ka BP and that of the Litorina Sea at an altitude of 6–14 m a.s.l., c. 7.3 cal. ka BP. The oldest traces of human activity dated to 8.5–7.9 cal. ka BP are associated with the palaeo‐Narva River in the period of low water level in the Baltic basin at the beginning of the Litorina Sea transgression. The coastal settlement associated with the Litorina Sea lagoon, presently represented by 33 Stone Age sites, developed in the area c. 7.1 cal. ka BP and existed there for more than 2000 years. Transformation from the coastal settlement back to the river settlement indicates a change from a fishing‐and‐hunting economy to farming and animal husbandry c. 4.4 cal. ka BP, coinciding with the time of the overgrowing of the lagoon in the Narva‐Luga Klint Bay area. 相似文献
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Analytical formulae for single P Cygni type saturated resonance line profiles in stellar winds have been derived. The limbdarkening
and presence of underlying intrinsic atmospheric profile have been ignored. The Sobolev approximation for radiative transfer
has been used and the general velocity law has been specified by widely used β parameter. The analytical formulae for the
saturated resonance line profiles can be found for cases when 2β is an integer. The formulae for 2β = 1,2, 3 and 4 have been
found by us. Also the formulae for calculating the line profiles in the cases of external and internal sharp truncation (cutoff)
of the scattering shell have been given. Some characteristic line profiles have been presented. It has been shown that the
turbulence-generated isotropic dominant backscattering of radiation in stellar winds generates wide dark plateaux in the blue
wings of spectral lines, and the slopes of plateaux are shaped by turbulence.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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