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Common environmental descriptors of two benthic amphi-atlantic mollusc assemblages
Absal?o, Ricardo S.;Moreira, J.;Troncoso, Jesus S.;
Brazilian Journal of Oceanography , 2006, DOI: 10.1590/S1679-87592006000100006
Abstract: two benthic mollusc assemblages of the continental shelf on both sides of the atlantic ocean, a tropical one in rio de janeiro, brazil, and another, temperate, in galicia, spain were investigated, with a view to finding common environmental descriptors which would explain, on a macro-scale, why these assemblages are there. both of the assemblages concerned show approximately the same species richness, about 150 taxa each. the molluscan fauna of both regions live on sandy sediments. the galician assemblages are at about 2-12 m depth, while those in rio de janeiro are at about 10-40 m depth. malacological assemblages were defined through cluster analysis and multiple discriminant analysis of the environmental data showed that each assemblage has its own environmental space. these assemblages have no species in common, but show the same phenological characters associated with each sedimentological facies. the same set of environmental variables (median sediment grain size, skewness, kurtosis, sorting, fine and medium sand fractions and depth) were selected as controlling these assemblages, suggesting that they play their role as general environmental descriptors.
Pátek, Levousy a Chlum any – vyznamné fosiliferní st edopleistocénní lokality na pravém b ehu Oh e mezi Louny a Libochovicemi Pátek, Levousy and Chlum any – important mid-pleistocene localities on the right bank of the Oh e River between Louny and Libochovice  [PDF]
Ji?í Kovanda,Ivan Horá?ek,Radka Symonová
Malacologica Bohemoslovaca , 2005,
Abstract: Due to a complete predominance of non-calcareous fluvial sediments in the Czech Republic, any find of fossil malacofauna is always considered as rare. The present work describes three localities in the Oh e river area, which contain, especially in the case of the Pátek locality, very abundant mid-Pleistocene malacofaunas. They were mainly collected in the floodplain fine-grained loam and back swamp deposits but also in sandy gravels. The molluscan thanatocenoses from localities near the Pátek village indicate the interglacial maximum (with up to 25 forest species s.l.), which developed directly on a 30 m thick river terrace dating back to the period, during which the Oh e river established its present-day easterly course. The fossil molluscs from the Levousy locality come from floodplain loam deposits as well as from the underlying sandy terrace gravels. The species distribution, nevertheless, indicates only a transitional glacial-interglacial period. The somewhat higher morphologic position of the locality, as well as that of another section at Chlum any, and complete predominance of local late Cretaceous material indicates that the Oh e river did not flow to the east yet during the accumulation of the floodplain deposits with molluscs, but still to the north, towards Bílina. The terrestrial malacofauna from the Chlum any section came from floodplain marls, particularly from sandy tufa deposits in the alluvium, which contains no forest-biotope elements, but the presence of the species Columella columella – distinct representative of our coldest“ loess deposits – is an absolute surprise, since the peak of production of the sandy tufa deposits has always been associated with climate optima of the interglacials and of the Holocene. Therefore, the described malacofaunas come from a boundary period, during which the Oh e river did not use its present-day valley (Levousy and Clum any) yet. Then, from the oldest time span, it took up for the first time its eastward course. Stratigraphy of the localities cannot be determined with a reasonable certainty in regard to the current controversial situation in Pleistocene chronology both in the northern foothills of the Alps and in the area of the classic“ localities belonging to the continental icesheet region in northern Germany (Kovanda 2005a). Altogether 12 mid-Pleistocene species of small mammals were found in thanaotocoenoses at localities Pátek and Levousy. Ostracod assemblages analysis was also undertaken (11 species in 8 samples were determined).
Palaeoenvironmental implication of the Plio-Pleistocene loess deposits in southern Tarim Basin
Hongbo Zheng,Huizhong Chen,Junji Cao
Chinese Science Bulletin , 2002, DOI: 10.1007/BF02902833
Abstract: The sedimentary characteristics, grain-size distribution, geochemical composition and surface characteristics of quartz grains, together with palaeoenvironmental reconnaissance, all point to an aeolian origin for the intercalated siltstone beds in the Plio-Pleistocene Artux and Xiyu Formations along the southern margins of the Tarim Basin, indicating that loess deposition in the region started, at least, in the Early Pliocene. Loess deposition in the southern Tarim Basin was a response to the global deterioration, which might be attributed to the uplift of the Tibetan Plateau.
Terrestrial mollusc records from Xifeng and Luochuan L9 loess strata and their implications for paleoclimatic evolution in the Chinese Loess Plateau during marine Oxygen Isotope Stages 24-22
B. Wu,N. Q. Wu
Climate of the Past (CP) & Discussions (CPD) , 2011,
Abstract: Marine Isotope Stages 24-22 is a key period of the Mid-Pleistocene Transition, however, its climate variability is still unclear. The coarse-grained loess unit L9, one of the most prominent units in the Chinese loess stratigraphy, yields a high potential terrestrial record of paleoclimatic and paleoenvironmental changes during this period. In this study, two high-resolution terrestrial mollusc records of L9 loess strata from the Xifeng and Luochuan sequences in the Chinese Loess Plateau were analysed. Our mollusc results show that the MIS 24, the early and late parts of MIS 22 were dominated by cold and dry climate. Relatively mild-humid climate occurred in MIS 23 and the middle part of MIS 22. The climatic conditions at Xifeng region were cooler and more unstable compared to Luochuan region. A comparison of mollusc species composition and other proxies of L9 strata (MIS 24-22) with those of L1 loess units (MIS 4-2) indicates that the L9 loess was not deposited under the most severe glacial conditions in Quaternary climate history as suggested in previous studies. Our study shows that climatic conditions in the Loess Plateau during the L9 loess forming period were similar to that of gentle glacials (MIS 24 and MIS 22) and interglacial (MIS 23), as suggested by the marine δ18O record. Three cooling fluctuations occurred at ~930 ka, 900 ka and 880 ka, which might hint to the global "900 ka cooling event". The "900-ka event" in the Loess Plateau does not seem to be a simple long glaciation, but rather several complex climatic fluctuations superposed on a general cooling trend. The uplift of the Tibetan Plateau and the general cooling experienced by the Earth during this period may have resulted in abundant dust sources and increased dust transport capability, as indicated by increased grain size and the mass accumulation rate of L9 loess.
Terrestrial mollusc records from Xifeng and Luochuan L9 loess strata and their implications for paleoclimatic evolution in the Chinese Loess Plateau during marine oxygen isotope stages 24–22  [PDF]
B. Wu,N. Q. Wu
Climate of the Past Discussions , 2010, DOI: 10.5194/cpd-6-2767-2010
Abstract: Marine Isotope Stages 24–22 is a key period of the Mid-Pleistocene Transition, however, its climate variability is still unclear. The coarse-grained loess unit L9, one of the most prominent units in the Chinese loess stratigraphy, yields a high potential terrestrial record of paleoclimatic and paleoenvironmental changes during this period. In this study, two high-resolution terrestrial mollusc records of L9 loess strata from the Xifeng and Luochuan sequences in the Chinese Loess Plateau were analyzed. Our mollusc results show that the MIS 24, the early and late parts of MIS 22 were dominated by cold and dry climate. Relatively mild-humid climate occurred in MIS 23 and the middle part of MIS 22. The climatic conditions at Xifeng region were cooler and more unstable compared to Luochuan region. A comparison of mollusc species composition and other proxies of L9 strata (MIS 24–22) with those of L1 loess units (MIS 4–2) reveals that the L9 loess was not deposited under the most severe glacial conditions in Quaternary climate history as suggested by previous studies. Our study shows that climatic conditions in the Loess Plateau during the L9 loess forming period were like that of gentle glacials (MIS 24 and MIS 22) and interglacial (MIS 23), as suggested by marine δ18O record. Three cooling fluctuations occurred at ~940–923 ka, 905–895 ka and 885–875 ka, which might be hints of the global "900 ka cooling event". The "900-ka event" in the Loess Plateau seems not a simple long glaciation but a complex of several climatic fluctuations superposed on a general cooling trend. The uplift of Tibetan Plateau and its adjacent regions during this period resulted in a rapid increase in source materials of desert and loess and an enhancement of winter monsoon, which would have amplified the effects of cooling climate on dust production and transport during MIS 24–22, as indicated by increased grain size and mass accumulation rate of L9 loess.
Palaeoenvironmental implication of the Plio-Pleistocene loess deposits in southern Tarim Basin

ZHENG Hongbo,CHEN Huizhong,CAO Junji,

科学通报(英文版) , 2002,
Abstract: The sedimentary characteristics, grain-size distribution, geochemical composition and surface characteristics of quartz grains, together with palaeoenvironmental reconnaissance, all point to an aeolian origin for the intercalated siltstone beds in the Plio-Pleistocene Artux and Xiyu Formations along the southern margins of the Tarim Basin, indicating that loess deposition in the region started, at least, in the Early Pliocene. Loess deposition in the southern Tarim Basin was a response to the global deterioration, which might be attributed to the uplift of the Tibetan Plateau.
Age Correlation of Loess with other Pleistocene Deposits on the Basis of TL and OSL Dating
Stanis aw Fedorowicz
Geochronometria , 2007, DOI: 10.2478/v10003-007-0013-2
Abstract: The author collected 26 samples from six loess profiles located in Poland and Ukraine and 16 samples from three galcigenic profiles in Lithuania. TL and OSL dates were obtained for the samples. The TL dates were calculated in the Gdańsk University laboratory and the OSL dates were obtained by the Institute of Physics Laboratory at the Silesian Technical University. The dating results were referred to the OSL = f(TL) chart. In respect of luminescent dating results, the Upper Vistulian loess shows a high similarity of TL and OSL dates. It means that loess formation took place in conditions conductive to ensure that solar radiation the grains were exposed to reduce the energy accumulated in them. The TL dates of Middle and Upper Vistulian loess are slightly older than the OSL dates. The largest discrepancies were found in soil sample dates. The analysis of glacigenic profile dates is not unambiguous. The fact that the TL dates are older than the OSL dates may mean that during deposition the conditions were not sufficiently conductive to reduce the energy stored earlier in the grains examined with the TL method. This time could have been sufficient to reduce the energy examined with the OSL method.
Geological peculiarities of the Pleistocene gravel and conglomerate deposits in the Upper Carniola, NW Slovenia
Ljubo ?lebnik
Geologija , 1994,
Abstract: An old interglacial Sava river bed with cliff walls up to 40 m deep into the old Pleistocene conglomerate deposist was exposed by excavation of two big gravel pits in the Sora field and in the valley of Naklo in Upper Camiola. The canyon was cut during the last interglacial period and again refilled with gravel in the lastglacial period. Conglomerate walls of the canyon were well polished by large quantities of rapidly moving material originating from nearby situated terminal moraines still partly preserved close to the present-day town of Radovljica.This curious geological occurrence discovered by human activity deserves to be protected as an interesting evidence of natural forces in the past.
Hominin Footprints from Early Pleistocene Deposits at Happisburgh, UK  [PDF]
Nick Ashton, Simon G. Lewis, Isabelle De Groote, Sarah M. Duffy, Martin Bates, Richard Bates, Peter Hoare, Mark Lewis, Simon A. Parfitt, Sylvia Peglar, Craig Williams, Chris Stringer
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0088329
Abstract: Investigations at Happisburgh, UK, have revealed the oldest known hominin footprint surface outside Africa at between ca. 1 million and 0.78 million years ago. The site has long been recognised for the preservation of sediments containing Early Pleistocene fauna and flora, but since 2005 has also yielded humanly made flint artefacts, extending the record of human occupation of northern Europe by at least 350,000 years. The sediments consist of sands, gravels and laminated silts laid down by a large river within the upper reaches of its estuary. In May 2013 extensive areas of the laminated sediments were exposed on the foreshore. On the surface of one of the laminated silt horizons a series of hollows was revealed in an area of ca. 12 m2. The surface was recorded using multi-image photogrammetry which showed that the hollows are distinctly elongated and the majority fall within the range of juvenile to adult hominin foot sizes. In many cases the arch and front/back of the foot can be identified and in one case the impression of toes can be seen. Using foot length to stature ratios, the hominins are estimated to have been between ca. 0.93 and 1.73 m in height, suggestive of a group of mixed ages. The orientation of the prints indicates movement in a southerly direction on mud-flats along the river edge. Early Pleistocene human fossils are extremely rare in Europe, with no evidence from the UK. The only known species in western Europe of a similar age is Homo antecessor, whose fossil remains have been found at Atapuerca, Spain. The foot sizes and estimated stature of the hominins from Happisburgh fall within the range derived from the fossil evidence of Homo antecessor.
QUATERNARY MARINE MOLLUSKS IN TIERRA DEL FUEGO: INSIGHTS FROM INTEGRATED TAPHONOMIC AND PALEOECOLOGIC ANALYSIS OF SHELL ASSEMBLAGES IN RAISED DEPOSITS
Gordillo,Sandra;
Anales del Instituto de la Patagonia , 2009, DOI: 10.4067/S0718-686X2009000200001
Abstract: during the quaternary the southern tip of south america was affected by several glaciations which might have excluded much of the benthic marine fauna inhabiting this region, with the consequent in-terruption of the connection between the atlantic and the pacific oceans. in that context, fossil marine mollusks recovered from interglacial (pleistocene) and postglacial (holocene) quaternary deposits of tierra del fuego, provide a key for the reconstruction of paleocommunities and the evaluation of changes in faunal composition over time. paleontological database was compiled from previous works, showing a diverse fauna, which includes 91 different species (61.5% gastropods; 31.9% bivalves and 6.6% chitons). quaternary time-averaged mollusk assemblages from tierra del fuego give a very good picture of the overall coastal benthic biodiversity patterns in the region. the composition of mollusk species showed remarkable similarities with present- day fauna, which reinforces the hypothesis that climatic conditions have maintained without significant changes since at least the middle pleistocene. however, taphonomic and paleoecological analysis of shell assemblages shows the existence of different shallow benthic com-munities, which represent spatial and temporal variations among regions and sites.
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