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The geologic framework is an important factor worth consideration when analyzing the development of seacoasts. The different coastal responses to hydrometeorological and anthropogenic factors depend on the composition and amount of original coast-forming sediments. The impact of sediment composition on morphometric parameters is best observed in areas where sand unrepresentative of the adjacent coastal sectors appears on beaches with a relatively uniform lithological composition. These areas are referred to as lithological anomalies. Large amounts of coarse-grained sand, uncharacteristic of the adjacent coastal sectors of the Curonian spit, accumulated in the area of the strait that existed in the Post-Littorina Late Subboreal (3.7–2.5 ka BP) time south of the Juodkrantė settlement. Due to accumulation of coarse sand, the beach in this sector is narrow and has a higher slope, and the ridge is lower and with a smaller volume of sand than in the adjacent coastal sectors. The specific sand composition and morphology of this coastal sector are responsible for different coastal dynamics during storms. During extreme storms, beach erosion in this coastal sector is minimal (sometimes even accretion takes place) compared with other sectors where beach erosion is rather substantial. Meanwhile, during periods of relatively calm weather, i.e. times of expected regeneration of the cross profile, this sector stands out for active erosion processes. [ABSTRACT FROM AUTHOR]

Abstract The reconstruction of the development of the northern Curonian Lagoon, Lithuania, during the Holocene is based on a wide suite of studies: pollen, diatom and carbonate analyses, measurements of magnetic susceptibility, as well as geochemical data. Recently published data from the Nida-VI borehole show that the age of lacustrine and lagoonal sand spans from Boreal to Sub-Atlantic. Diatom analyses reveal changes in the groups of brackish-fresh and fresh-brackish species and show relatively rapidly changing environmental conditions that could have existed through the ongoing Litorina Sea transgression. The Curonian Spit separated a semi-closed lagoon by the end of Atlantic − beginning of Subboreal, with "lagoon marl" layer deposited during the Litorina Sea stage. The paleo-lagoon became shallow and freshwater during the Subatlantic. The topmost sediment in the section is nearly devoid of diatom valves likely due to high accumulation rates of sand. Climate shifts and local environmental conditions were distinguished based on carbonate content, with lower values associated with colder periods. The increase in carbonate fraction during the late Atlantic is related mostly to warmer Holocene climate phases. Based on Al/Ti oxide ratio, the Boreal climate was arid and the Early Atlantic largely transitional, whereas the late Atlantic was humid. The absence of negative Ce anomalies, as well as U/Th ratios, suggest that a rather oxic regime prevailed during sedimentation. The origin of several cycles of variation in Zr/Rb may indicate increased weathering. Down core variations in bulk volume magnetic susceptibility closely mirror the textural and compositional trends, with peaks likely reflecting pulses of terrigenous influx during dry periods. [ABSTRACT FROM AUTHOR]