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- Obere Jordantal (1) (remove)
In this dissertation, a multi-proxy study, which included palaeoecological, lithological, geochemical and geochronological methods, was carried out to investigate climatic and environmental changes and their interaction during the Quaternary in formerly glaciated and non-glaciated areas. The information obtained will be used to provide a better understanding of the regional stratigraphic framework and to establish broader regional terrestrial correlations within the global marine isotope stage (MIS) framework. This study was conducted on two key drillings, the Garding-2 research drill core in the German North Sea coastal area of Schleswig-Holstein and the GBY#2 archaeological core at the Gesher Benot Ya´aqov (GBY) site, in the Upper Jordan Valley in Israel. The results of this study are presented in three papers. Papers I and II focus on the study of the Garding-2 core, while the multi-proxy study of the GBY#2 core is presented in Paper III. The results of a variety of analyses conducted on the 240 m long Garding-2 sequence show interglacial-glacial cycles that are mainly controlled by variations in temperature. This sequence is composed of mainly fluvial-shallow marine sediments intercalated by muddy-peaty deposits. Based on the palynological and lithological findings, the Pliocene-Pleistocene transition was observed at 182.87 m. It is overlain by Praetiglian and the subsequent sediments of the Waalian and Bavelian Complexes. The boundary of either the second or third Cromerian Interglacial with younger sediments, which still belong to MIS 19, is marked by the last occurrence of Tsuga at 119.50 m and the development of mixed-deciduous forests. The palynologically equivalent sediments of the Bilshausen Interglacial were found below two Elsterian till layers, at 89.00 m-82.00 m. These sediments showed high and increased percentages of Pinus and Picea and scattered occurrences of Abies and Carpinus, which are similar to the features of the beginning of the Bilshausen or Rhume interglacial (Müller, 1992). An unconformity occurred at 80.29 m, at the bottom of late Holsteinian deposits, characterised by the occurrences of Fagus and Pterocarya, with low percentages of Abies and Carpinus and the absence of Buxus. These deposits are succeeded by sediments of the Fuhne cold period that shows higher percentages of NAP and occurrences of Ericales, Helianthemum and Selaginella selaginoides, which are unconformably overlain by Drenthian till at 73.00 m-71.00 m. A single peaty sample at 69.25 m with Pinus-Picea-Abies assemblage is correlated with the late Eemian Interglacial. This deposit is overlain by Weichselian glaciofluvial sediments. Middle-late Holocene sediments occurred from 20 m upwards, following a hiatus, which was caused by the Early Holocene transgression. A subsequent thin layer of marine Atlantic sediments is unconformably overlain by marine-tidal flat deposits up to 11.00 m. The first occurrence of Fagus (at 15.97 m) and Carpinus (at 15.03 m), which was optically stimulated luminescence (OSL)-dated to 3130 +/- 260 BP (at 16.22 m, Zhang et al., 2014), gives evidence for a Subboreal age for these deposits. Sandy sediments of the early Subatlantic, which were deposited between 11.00 m and the top of the Garding-2 sequence, indicate that local salt marshes, dunes and tidal flat vegetation expanded during this period. Due to regional features and the peculiarities of the local coastal environment, the expansions of Fagus and Carpinus, which are characteristic for the Subboreal-Subatlantic transition at about 2700 BP in northern Germany, are not clearly reflected in the Garding-2 pollen diagram. In the Mediterranean area, a 50 m long core of GBY#2, was drilled at the Acheulian site of Gesher Benot Ya´akov. The GBY#2 core provides a long Early-Middle Pleistocene geological, environmental and climatological record, which also enriches the knowledge of hominin-habitat relationships documented at the margins of the Hula Palaeo-lake. The sediment sequence of GBY#2 is under- and overlain by two basalt flows that are 40Ar/39Ar dated: two samples at the bottom of the core dated to 1195 +/- 67 ka (at 48.30 m) and 1137 +/- 69 ka (at 45.30 m), and another one at the top dated to 659 +/- 85 ka (at 14.90 m). With the additional chronological identification of the Matuyama Brunhes Boundary (MBB) and the correlation with the GBY excavation sites, the sedimentary sequence of GBY#2 provides the climatic history during the late part of the mid-Pleistocene transition (MPT, 1.2 Ma-0.5 Ma). Multi-proxy analyses including those of pollen and non-pollen palynomorphs, macro botanical remains, molluscs, ostracods, fish, amphibians and micromammals provide evidence for lake and lake-margin environments during MIS 20 and MIS 19. During MIS 20, relatively cool semi-moist conditions were followed by a pronounced dry phase. During the subsequent MIS 19, warm and moist interglacial conditions were characterised by Quercus-Pistacia woodlands in this area. The depositional environment changed from an open water lake during MIS 20 to a lake margin environment in MIS 19. This finding is at odds with changing climate conditions from relatively dry to moist. This discrepancy could be explained by the prograding pattern of the lake shore due to the infilling of the basin, which resulted in shallower water. Climatic changes during the Late Tertiary and the Quaternary in the high latitude regions in northwest Europe and during the Early-Middle Pleistocene in the mid latitude regions of the Middle East follow the patterns of global climatic changes, which are mainly controlled by orbital obliquity (+/-41 ka cycle) during the Early Pleistocene and by orbital eccentricity (+/-100 ka cycle) during the MPT (1.2 Ma-0.5 Ma) and the younger periods of the Quaternary. The results of this study also provide reliable evidence for long distance correlation of stratigraphic and climatic events of the Quaternary, which extends knowledge of regional and global impact of climatic fluctuations on the environment.