The potential of micromorphology for interpreting sedimentation processes in wetland sites: a case study of a Late Bronze–early Iron Age lakeshore settlement at Lake Luokesa (Lithuania)

Abstract

Lake Luokesa lies in the eastern part of Lithuania and is part of a region of lakes formed by the Scandinavian ice-sheet and its melt waters during the last glaciation. During the Late Bronze-Early Iron Age transition, between 625 and 535 cal BC, a lakeside settlement with an onshore palisade was built on the platform of a carbonate bank. A total of five profiles, each comprising an organic occupation layer and lake sediments at its bottom and top, were examined micromorphologically. In this paper, natural and anthropogenic processes that led to the formation of the individual layers are presented; their possible origins are reconstructed and then discussed and compared to lakeside settlements of the circum-alpine region. This includes the emergence of lake marl, accumulation of organic layers in the settlement area as well as their decomposition, erosion and trampling features and inwash of sand through runoff from the hinterland. Due to the accumulation of the up to 60 cm thick culture layers in waterlogged environments, indications of seasonal deposition cycles could be identified.Keywords Site formation processes Á Seasonality Á Human impact Á Trampling Á Erosion Á Geoarchaeology Communicated by M. Latałowa.

Lacustrine, fluvial and slope deposits in the wetland shore area in Serteya, Western Russia

“…4A), with single fine charcoal fragments. It may represent the natural accumulation of organic material in the transition zone between the lake and land, but anthropogenic settlement activities, too, should be taken into account as a primary forming factor, as in the case of similar contexts (albeit with more numerous and differentiated anthropogenic inclusions) investigated at Lake Luokesa (Lithuania) and several Swiss lakeshore sites (Ismail-Meyer et al 2013;Ismail-Meyer 2014). The relatively good state of preservation of the plant remains and only limited presence of soil fauna excrements (mites) indicate a considerably high accumulation rate, rapid burial and generally waterlogged conditions (Fe/Mn ratio above 280 and Ca/Fe ratio above 1.5) of the deposit at the depth 109-110 cm b.g.l.…”

“…4B, C), similar to material building the OSOM (see below). A combination of inland and littoral factors may have been responsible for the formation of the SOM: erosion of the upper sandy slopes of the kame and the resulting sedimentation of runoff downslope have to be considered (Ismail--Meyer et al 2013;Ismail-Meyer 2014). Also, the possibility that both the OM and SOM may have been (re)worked by episodic increases in the lake water level should be acknowledged, although no diatoms and only single sponge spicules were discovered.…”

Palynological investigations at the Late Bronze–Early Iron Age lakeshore settlement of Luokesa 1 (Moletai District, Lithuania): a contribution to the Middle-Late Holocene vegetation history of the south-eastern Baltic regions

“…At L1, the proportion of plant remains represents over 50 % of the material throughout: in most cases it is composed of fragments of wood and bark, but twigs, leaves, fruits, seeds, charcoal and mosses are also present. Clay, sand and gravel are also documented (Pollmann 2014;Ismail-Meyer 2014). Much of this material was intentionally brought to the site as consumables, building and insulation material, produce from harvests and gathering, and bedding for livestock; much also reached the settlement accidentally.…”

Do still waters run deep? Formation processes of natural and anthropogenic deposits in the Neolithic wetland site Zug‐Riedmatt (Switzerland)

“…After polymerization, they were cut into several sections with a diamond saw. To produce the 30 μm thin sections, the sections were cut into 47 × 47 mm blocks (Beckmann, 1997; Ismail‐Meyer, 2014). A total of 90 thin sections have been analysed from the 12 reference profile columns containing 225 macroscopically recognizable layers.…”

“…Simultaneously, dendrochronological analyses yielded exact dates for many settlements (e.g., Bleicher & Harb, 2015; Bleicher & Harb, 2017; Ebersbach, Ruckstuhl, & Bleicher, 2015; Harb & Bleicher, 2016; Jacomet, Leuzinger, & Schibler, 2004; Menotti & O'Sullivan, 2015; Menotti, 2012). Since the late 1970s, several sites have been analysed sedimentologically (e.g., Brochier, 1983; Joos, 1980) and in the 1990s, additional micromorphological analyses were adopted (e.g., Ismail‐Meyer, 2014; Ismail‐Meyer & Rentzel, 2004; Karkanas et al, 2011; Ostendorp, 1990; Pümpin, Wiemann, & Rentzel, 2015; Wallace, 1999). Pile‐dwelling research has shown that in this wet‐dry environment complex processes of preservation, degradation, reworking, and sedimentation occur.…”