Simulation of proglacial lake shore displacement in Estonia

Abstract

The Late Glacial shoreline database compiled for Estonia covers 149 sites on the proglacial lakes A1 (Voose) and A2 (Kemba). Eighty-two sites were used in further simulations. Point kriging interpolation with a linear trend approach was applied to create interpolated surfaces of water levels for checking the spatial correctness of data. The sites with altitudes visually not matching with sites nearby were discarded, as well as those with residuals of more than 1 m and 0.7 m respectively. The final surfaces were analysed geostatistically by simulating isobases, direction of tilting, and shoreline gradient. The simulated isobases suggest that both proglacial lakes A1 and A2 were connected with the glacial lake in the Lake Peipsi basin. The interpolated surface aspect shows that the direction of tilting varies between 320° and 340°. The surface gradient of lake A1 is highest in the NW and SE parts of the study area (50 and 25 cm km–1, respectively), and that of lake A2  is highest in the NW and SE parts (40 and 20 cm km–1, respectively). Using the modelling data, the shoreline correlation between the two proglacial lakes has been revised