Temperate Intervals Research Articles

Climate adaptation of pre-Viking societies

Understanding how the Viking societies were impacted by past climate variability and how they adapted to it has hardly been investigated. Here, we have carried out a new multi-proxy investigation of lake sediments, including geochemical and palynological analyses, to reconstruct past changes in temperature and agricultural practices of pre-Viking and Viking societies in Southeastern Norway during the period between 200 and 1300 CE. The periods 200–300 and 800–1300 CE were warmer than the 300–800 CE period, which is known as the “Dark Ages Cold Period”. This cold period was punctuated by century-scale more temperate intervals, which were dominated by the cultivation of cereals and hemp (before 280 CE, 420–480 CE, 580–700 CE, and after 800 CE). In between, cold intervals were dominated by livestock farming. Our results demonstrate that the pre-Viking societies changed their agricultural strategy in response to climate variability during the Late Antiquity.

An Early Pleistocene hippopotamus from Westbury Cave, Somerset, England: support for a previously unrecognized temperate interval in the British Quaternary record

ABSTRACTAlthough fossil assemblages from the late Early Pleistocene are very rare in Britain, the site of Westbury Cave in Somerset, England, has the potential to address this gap. The mammal fossils recovered previously from the Siliceous Member in Westbury Cave, though few in number, have hinted at an age for the deposits that is as yet unparalleled in Britain. Here, we describe the first bona fide occurrence of Hippopotamus in the British Early Pleistocene, discovered during recent reinvestigation of the Siliceous Member. The hippo fossil indicates a refined biochronological age of ca. 1.5–1.07 Ma for the Siliceous Member and a palaeoclimate that was warm and humid, which accords well with previous palaeoenvironmental inferences. A synthesis of late Early Pleistocene hippo occurrences suggests that the Siliceous Member hippo may have been part of an early colonization of north‐west Europe by these megaherbivores, possibly during MIS (Marine Oxygen Isotope Stage) 31. Alternatively, it evidences a currently cryptic northward migration during an even earlier temperate phase. In either case, the Siliceous Member is likely to represent a warm period that has not been recognized previously in the British Quaternary record.

Concurrent Heat and Intermittent Hypoxic Training: No Additional Performance Benefit Over Temperate Training.

To examine whether concurrent heat and intermittent hypoxic training can improve endurance performance and physiological responses relative to independent heat or temperate interval training. Well-trained male cyclists (N = 29) completed 3 weeks of moderate- to high-intensity interval training (4 × 60 min·wk-1) in 1 of 3 conditions: (1)heat (HOT: 32°C, 50% relative humidity, 20.8% fraction of inspired oxygen, (2)heat + hypoxia (H+H: 32°C, 50% relative humidity, 16.2% fraction of inspired oxygen), or (3)temperate environment (CONT: 22°C, 50% relative humidity, 20.8% fraction of inspired oxygen). Performance 20-km time trials (TTs) were conducted in both temperate (TTtemperate) and assigned condition (TTenvironment) before (base), immediately after (mid), and after a 3-week taper (end). Measures of hemoglobin mass, plasma volume, and blood volume were also assessed. There was improved 20-km TT performance to a similar extent across all groups in both TTtemperate (mean ±90% confidence interval HOT, -2.8% ±1.8%; H+H, -2.0% ±1.5%; CONT, -2.0% ±1.8%) and TTenvironment (HOT, -3.3% ±1.7%; H+H, -3.1% ±1.6%; CONT, -3.2% ±1.1%). Plasma volume (HOT, 3.8% ±4.7%; H+H, 3.3% ±4.7%) and blood volume (HOT, 3.0% ±4.1%; H+H, 4.6% ±3.9%) were both increased at mid in HOT and H+H over CONT. Increased hemoglobin mass was observed in H+H only (3.0% ±1.8%). Three weeks of interval training in heat, concurrent heat and hypoxia, or temperate environments improve 20-km TT performance to the same extent. Despite indications of physiological adaptations, the addition of independent heat or concurrent heat and hypoxia provided no greater performance benefits in a temperate environment than temperate training alone.

A new high-resolution pollen sequence at Lake Van, Turkey: insights into penultimate interglacial–glacial climate change on vegetation history

Abstract. A new detailed pollen and oxygen isotope record of the penultimate interglacial–glacial cycle, corresponding to the marine isotope stage (MIS) 7–6, has been generated from the Ahlat Ridge (AR) sediment core at Lake Van, Turkey. The presented Lake Van pollen record (ca. 250.2–128.8 ka) displays the highest temporal resolution in this region with a mean sampling interval of ∼ 540 years.The integration of all available proxies shows three temperate intervals of high effective soil moisture availability. This is evidenced by the predominance of steppe-forested landscapes (oak steppe-forest) similar to the present interglacial vegetation in this sensitive semiarid region between the Black Sea, the Caspian Sea, and the Mediterranean Sea.The wettest and warmest stage, as indicated by highest temperate tree percentages, can be broadly correlated with MIS 7c, while the amplitude of the tree population maximum during the oldest penultimate interglacial (MIS 7e) appears to be reduced due to warm but drier climatic conditions. The detailed comparison of the penultimate interglacial complex (MIS 7) to the last interglacial (Eemian, MIS 5e) and the current interglacial (Holocene, MIS 1) provides a vivid illustration of possible differences in the successive climatic cycles. Intervening periods of treeless vegetation can be correlated with MIS 7d and 7a, in which open landscapes favor local erosion and detrital sedimentation. The predominance of steppe elements (e.g., Artemisia, Chenopodiaceae) during MIS 7d indicates very dry and cold climatic conditions. In contrast, the occurrence of higher temperate tree percentages (mainly deciduous Quercus) throughout MIS 7b points to relatively humid and mild conditions, which is in agreement with other pollen sequences in southern Europe.Despite the general dominance of dry and cold desert-steppe vegetation during the penultimate glacial (broadly equivalent to MIS 6), this period can be divided into two parts: an early stage (ca. 193–157 ka) with higher oscillations in tree percentages and a later stage (ca. 157–131 ka) with lower tree percentages and subdued oscillations. This subdivision of the penultimate glacial is also seen in other pollen records from southern Europe (e.g., MD01-2444 and I-284; Margari et al., 2010; Roucoux et al., 2011). The occurring vegetation pattern is analogous to the division of MIS 3 and MIS 2 during the last glacial in the same sediment sequence. Furthermore, we are able to identify the MIS 6e event (ca. 179–159 ka) as described in marine pollen records, which reveals clear climate variability due to rapid alternation in the vegetation cover.In comparison with long European pollen archives, speleothem isotope records from the Near East, and global climate parameters (e.g., insolation, atmospheric CO2 content), the new high-resolution Lake Van record presents an improved insight into regional vegetation dynamics and climate variability in the eastern Mediterranean region.

Preparation of forsterite/MBS (MgO-B 2 O 3 -SiO 2 ) glass-ceramic composites via conventional and microwave assisted sintering routes for LTCC application

Abstract The present work aims to investigate sinter-crystallization as well as thermal properties and microwave dielectric features of forsterite/MBS (MgO-B 2 O 3 -SiO 2 ) glass-ceramic composites prepared through conventional and microwave assisted sintering procedures. Microwave sintered composites offered better sinterability compared to the conventionally sintered composites all over the sintering temperate interval. It was found that the optimum densification occur for the 30:70 forsterite/MBS glass-ceramic composite at temperature of 850 °C. In all fabricated composites, suanite and enstatite were crystallized from the glass matrix. According to the FESEM observation, microstructure of the optimized composite was composed of dendritic crystals of suanite and enstatite crystallized from the glass matrix around forsterite particles. The most promising conventionally sintered composite had low dielectric constant (5.8), near zero thermal coefficient of resonance frequency as well as quality factor of 18312 GHz.

Long (MIS 5e – 3) environmental history of a paleolake in central Poland recorded in the succession from Kubłowo

One of the longest (above 7 m thick) uninterrupted Eemian-Vistulian (Weichselian) pollen successions in Poland is known from Kubłowo (central Poland). The huge importance of this succession is manifested in the possibility of study the evolution of the lake environment under the influence of changing, from interglacial to glacial climatic conditions.The reconstruction of the environmental changes at Kubłowo and its surroundings show the short climate fluctuations and a detailed picture of the natural conditions prevailing in central Poland (central Europe) during the period from approximately 126,000 to 55,000 years BP. Based on the results of multi-proxy analysis, four lacustrine stages linked with a higher water level and three boggy stages (low water level) of evolution of the Kubłowo paleolake were observed.The pollen diagram from Kubłowo reveals a succession of eighteen local pollen assemblage zones (K1-K18 L PAZ). The K1 to K7 LPAZ zones record the interglacial succession correlated with the Eemian. The next pollen zones, K8 to K18, are linked with the Vistulian. The pollen sequence shows, between the Eemian Interglacial (MIS 5e) and the last glaciation (second stadial of the Plenivistulian (MIS 4-3), four cold intervals that are interpreted as stadial phases: Herning, Rederstall, Schalkholtz and Ebersdorf separated by three temperate intervals (interstadials): Brörup, Odderade and Oerel.In the studied sediments, 25 species of subfossil Cladocera were identified, and ten zones of fauna development were distinguished. The unique feature of this profile is the good preservation of above 100,000-year-old Cladocera remains and a high diversity of species, which are primarily littoral. The Middle and Late Eemian were periods convenient to Cladocera development due to high temperatures, high water levels, high trophy and occurrence macrophytes. A deterioration of fauna living conditions started in the Late Eemian and next took place in the Vistulian cold events.The results of isotopic and geochemical analyses of organic matter from Kubłowo have enabled the reconstruction of varying environmental conditions and the origin of organic matter. The organic carbon content (TOC) changes from 1% to 40% and is closely related to climatic conditions. During the Eemian, the amount of TOC systematically increased. The lowest values are recorded in the coldest periods during the Herning, Rederstall and Schalkholz Stadials. The C/N atomic ratio fluctuates from 13 to 34 and the highest values occur in the Brörup Interstadial. The values of δ13C change from −27.9 to −12.9‰, and δ15N values oscillate between −1.6 and +5.3‰.

The δ18O stratigraphy of the Hoxnian lacustrine sequence at Marks Tey, Essex, UK: implications for the climatic structure of MIS 11 in Britain

ABSTRACTMarine Isotope Stage 11 (MIS 11) is considered one of the best analogues for the Holocene. In the UK the long lacustrine sequence at Marks Tey, Essex, spans the entirety of the Hoxnian interglacial, the British correlative of MIS 11c. We present multiproxy evidence from a new 18.5‐m core from this sequence. Lithostratigraphy, pollen stratigraphy and biomarker evidence indicate that these sediments span the pre‐, early and late temperate intervals of this interglacial as well as cold climate sediments that post‐date the Hoxnian. The δ18O signal of endogenic carbonate from this sequence produces several clear patterns that are interpreted as reflecting the climatic structure of the interglacial. As well as providing evidence for long‐term climate stability during the interglacial and a major post‐Hoxnian stadial/interstadial oscillation the δ18O signal provides strong evidence for abrupt cooling events during the interglacial itself. One of these isotopic events occurs in association with a short‐lived increase in non‐arboreal pollen (the NAP phase). The results presented here are discussed in the context of other MIS 11 records from Europe and the North Atlantic, particularly with respect to our understanding of the occurrence of abrupt climatic events in pre‐Holocene interglacials. Copyright © 2016 The Authors. Journal of Quaternary Science Published by John Wiley & Sons Ltd.

Quaternary fluvial, pedogenic and mass-movement processes at St George's Down, Newport, Isle of Wight

Recent geological mapping on the Isle of Wight by the British Geological Survey has shown the ‘Plateau Gravel’ to be a mixture of fluvial, solifluction, pedogenic and marine deposits ranging from pre-Anglian to Holocene age. As part of the resurvey of the island, several new exposures of the ‘Plateau Gravel’ between Newport and Downend were examined. A working gravel pit on St George's Down, near Newport, revealed a succession of flint gravels with an inter-bedded sequence of laminated silts. An upper in situ succession of pre-Anglian fluvial gravels caps the plateau, but a second, probably younger suite of gravel-rich sediments is exposed in a quarry on a topographically lower spur. These overlie in situ Clay-with-flints resting on Upper Cretaceous Chalk. These lower sediments are well exposed and display a complex stratigraphy. They consist predominantly of flint gravel, but include a dipping succession of laminated silts and palaeosols preserved in a hollow or small channel feature, intercalated between two distinct soliflucted cold-stage gravel sheets. Palynological and pedological evidence analysis suggests that these laminated silts and sands were deposited under a temperate climate but with frequent episodes of disruption caused by mass-movement and possibly freeze–thaw. The age of these laminated sediments are not known with any certainty but are likely to date to a temperate interval within the Late Pleistocene. The top of the laminated unit is cut by a heavily cryoturbated horizon presumed to be of Devensian age.

Microfossils in the upper quaternary sediments of the Norwegian Sea (biostratigraphy and paleoceanology)

Diatom and nannoplankton microfossils in the samples of the surface bottom sediments and cores from the western part of the Norwegian Sea (64°–79°N) were studied. The abundance, distribution, taxonomic composition, and structure of the assemblages are determined by the productivity and temperature of the surface waters, by the distance from the shore, by the hydrological setting, and by the intensity of the supply of the Atlantic (from the south) and Arctic (from the north) waters to the Norwegian Sea. The repeated changes in the ecological structure of the diatom assemblages with time allowed us to distinguish five different ages and to estimate the changes in the paleoenvironment in the region under study during the past ∼19–21 ky. The nannofossil distribution is not universal over the entire area studied owing to the extreme northern location of the stations and low water temperatures. All the sediments examined refer to the Emiliania huxleyi zone of the Late Pleistocene-Holocene; in selected cases, narrower temperate and cold-water intervals were also recognized. The low species diversity and the poor preservation of nannofossils prove the dominating influence of the Arctic water masses.

Stone runs in the Falkland Islands: Periglacial or tropical?

“Stone runs” is the Falklands vernacular term for openwork boulder accumulations, which include extensive blockstreams like the famous Darwin “stone-river” and associated features such as stone stripes. Since the early 20th century, they have been interpreted as the product of a suite of periglacial processes, including frost-wedging, gelifluction, frost heave, frost-sorting and snowmelt runoff. Following a literature review, the results of recent field investigations of the valley-floor blockstreams of East Falkland are presented. Access to the internal structure of these forms provides evidence for the existence of a three-fold profile, with clear vertical size gradation presenting striking similarities with an inverted weathering profile. Micromorphological analyses, SEM, XRD, thin sections and grain-size analyses lead to the hypothesis of an alternative model of stone run formation. It is suggested that the material forming the stone run profile lato sensu (including the superficial pavement) is not of periglacial origin, but derives directly from the stripping and accumulation downslope of a regolith, possibly Tertiary in age and formed under subtropical or temperate conditions. The valley-floor stone runs should, therefore, be considered as complex polygenetic landforms that may have formed according to a six-stage scenario, including in situ chemical weathering, regolith stripping by mass movements, soil formation, further regolith stripping, downslope accumulation and matrix washing-out (all phases possibly achieved by the Early Quaternary). Periglacial reworking of the stone run material would have operated at a “final” stage, i.e. during Quaternary cold stages, with boulder bioweathering and limonite-staining operating during the temperate intervals including the present one. The suggested antiquity of the Falklands blockstreams is in accordance with Caine's pioneer interpretation of Tasmania blockfields and with recent analyses and cosmogenic datings of blockfields from Scandinavia and North America.

Towards an understanding of the response of southern European vegetation to orbital and suborbital climate variability

In recent years, the generation of high-resolution terrestrial and marine long pollen sequences with improved chronological control has provided new insights into the vegetation response in southern Europe to orbital and suborbital climate variability. Here a synthesis of our current understanding of the phase and amplitude relationships between climate forcing and vegetation changes is presented. What emerges is that on orbital frequencies the timing of interglacial forest expansion is closely linked to the summer insolation maximum, but does not have a fixed lag relative to the mid-point of the deglaciation, which may vary from one Termination to another. For the closing phases of interglacials, the available evidence suggests that forest in southern Europe usually extends into the interval of ice growth. However, suborbital variability may override the diachronous relationship between glacial inception and forest decline, leading to a premature ending of forest periods. During glacial intervals, there is a close correspondence between tree-population size and ice volume extent, while during temperate intervals, the extent of forest development is closely related to the amplitude of insolation and associated climate regimes, but may diverge from the extent of residual ice volume. On suborbital frequencies, changes in tree-population size are in phase with climate forcing, while the amplitude of these changes is modulated by geographical position and local factors. Finally, orbital mean state can lead to the modulation of the amplitude of suborbital-scale variability. Examination of additional climatic cycles and increased resolution (better than 200 years) are needed to test further these preliminary conclusions.

Paleoecology, stratigraphy and taxonomy of the pliocene marine diatoms from central crete (Greece)

A rich siliceous phytoplankton assemblage of late Early Pliocene to early Late Pliocene age, containing 31 genera of marine diatoms with 55 specific taxa, was found in fine laminated diatomite beds in the sections of Kallithea, Marathitis, Prassas and Aitania from the northern central part of the Crete Island (Province of Heraklion, Greece). The sediments of the studied sections belong to the upper part of the Stavromenos facies-unit (Early to Late Pliocene). The diatom associations were mainly investigated for their paleoecology, stratigraphy and taxonomy. The diatom assemblages are characterized by species typical of low latitudes. They belong to the upper part of the Nitzschia jouseae biozone (Early Pliocene — Late Pliocene) because of the presence of the marker species N. jouseae, which is rare to frequent in the Kallithea and the Marathitis sections, and rare in the Prassas and Aitania sections. The upper part of the N. jouseae biozone corresponds to the CN11b ( Discoaster asymmetricus) and CN12a ( D. tamalis) subzones of calcareous nannofossils as well as to the Globorotalia puncticulata and Gl. bononiensis biozones of planktic foraminifera. Among the diatoms the planktie, centrie species dominate in terms of their percentage distribution and reflect a succession of two paleoclimate intervals : a subtropical interval with the warm-water species Azpeitia nodulifer, Hemidiscus cuneiformis and Thalassiosira leptopus and a temperate interval characterized by the cold-water species Coscinodiscus marginatus. These two intervals are proposed as two new local acme subzones.

Climatic reconstruction of the Weichselian Pleniglacial in northwestern and Central Europe

A multiproxy approach is applied to reconstructing accurately the Weichselian Pleniglacial climate (72–13 ka) in northwestern and central Europe. Standardised translations are used to transform proxy data into climate parameter values for six characteristic time windows. Quantitative reconstructions of the temperature regime are derived from periglacial, Coleoptera and botanical evidence, while aeolian and fluvial evidence provide qualitative information on wind activity and precipitation respectively. The Early Pleniglacial (74–59 ka), the cold period between 41–38 ka and the Late Pleniglacial (27–13 ka) are characterised by a strong north to south climatic gradient over northwestern Europe. During the last-glacial maximum discontinuous permafrost was established in northern France, whereas the continuous permafrost zone extended from the UK, Belgium, The Netherlands, Germany and Poland to the nordic ice sheets. Prominent wind activity and a relatively low precipitation typify these periods. In contrast, an indistinct west to east climate gradient was present in the relatively more temperate intervals (e.g. 50–41 ka). Seasonally frozen ground conditions prevailed in northwestern Europe whereas discontinuous permafrost may be suggested for central Germany. It appears that the climate conditions in northwest and central Europe were controlled by three major factors: the Scandinavian ice sheet, the North Atlantic surface water (circulation) and the Russian continent. © 1998 John Wiley & Sons, Ltd.

Palynology, aminostratigraphy and U-series dating of marine gortian interglacial sediments in cork harbour, Southern Ireland

Palynological analysis, amino acid epimerization analysis and uranium thorium disequilibrium age determination of three Irish interglacial cores support the suggestion that there may have been more than one Holsteinian-style temperate interval in Europe. The cores were taken from estuarine deposits beneath glacial diamicton in Cork Harbour, southwest Ireland. The pollen records an incomplete temperate stage. The biotic signature is similar to those from several interglacial sites in Ireland and is considered part of the Gortian group. The pollen signature is Holsteinian/Hoxnian in character. Amino acid epimerization analysis suggests the deposits to be Oxygen Isotope Stage 7 in age, whereas uranium–thorium disequilibrium suggests a minimum Stage 5 age. Possible correlatives of the Gortian group in Europe are suggested.

VOLCANIC MAARS, LONG QUATERNARY SEQUENCES AND THE WORK OF THE INQUA SUBCOMMISSION ON EUROPEAN QUATERNARY STRATIGRAPHY

Abstract For several years the INQUA Subcommission on European Quaternary Stratigraphy (SEQS) has been actively fostering debate on the stratigraphy and typification of the Middle Pleistocene in Europe. Palynological investigations of deep sediment cores from maar lakes in Italy and the French Massif Central have now provided a stratigraphical framework conclusively correlated with the deep ocean record, confirming the occurrence of two clearly temperate intervals between the Holsteinian and Eemian Interglacials. This places interglacial deposits from localities such as Schoningen, Pritzwalk (Domnitz), Wacken and Maastricht-Belvedere into a clearer perspective. All major Saalian glacial advances probably relate to Oxygen Isotope Stage 6. Reasons for the relative paucity of continental interglacial deposits equivalent to Oxygen Isotope Stages 7 and 9 are discussed. These Stages were not preceded by major glacial events in northern Europe, so suitable basins of deposition were largely absent; in contrast fluvial erosion was very active, with much downcutting and drainage re-organisation. Finally evidence from the sea-surface temperature record of the Norwegian Sea does suggest a less powerful pattern of oceanic circulation in the North Atlantic during these interglacial intervals within the Saalian Complex Stage, when compared to those of the Eemian and Holocene. This difference would certainly have affected environments on the adjacent European continent.

Plio-pleistocene palaeogeography of the southern north sea basin (3.75-0.60 Ma)

Palaeogeographical maps are presented for the southern North Sea basin, from approximately 1°W to 7°E, and 51–55°N, for the period from approximately 3.75-0.60 Ma. Reconstructions centre on: 3.75 Ma (Coralline CragBrunssumian); 2.55 Ma (Red Crag/Brielle Ground/Reuverian); 2.40 Ma (Red Crag/Westkapelle Ground/Praetiglian-Early Tiglian); 2.00 Ma (Norwich Crag/Smith's Knoll and IJmuiden Ground/Middle Tiglian); 1.75-1.70 Ma (Cromer Forest Bed (Paston)/Winterton Shoal/Late Tiglian-Eburonian); 1.40 Ma (Kesgrave/Yarmouth Roads/Waalian); 1.15 Ma (Kesgrave/Yarmouth Roads/Menapian); and 0.60 Ma (Cromer Forest Bed (West Runton)/Yarmouth Roads/Cromerian Complex). From 3.75-2.40 Ma the basin is mainly a marine area fringed to the east and south by fluviatile deposition, and broadly open via the southwest to the Atlantic. Following marked marine regression and cooling at around 2.40 Ma, the period from 2.00-1.70 Ma is mainly one of renewed marine transgression and warmer conditions, during which a Great European delta built out, fed mainly from the east and south, into the southern North Sea. From 1.40-0.60 Ma marine waters were almost entirely excluded from the area, and temperate intervals alternated with increasingly glacial episodes, whilst the Great European delta continued to expand northwards into the northern North Sea.

Palaeoenvironmental and stratigraphic significance of the Valley Farm and Barham Soils in Eastern England

The Valley Farm and Barham Soils are important stratigraphic units representing an Early and/or Middle Pleistocene depositional hiatus within parts of Eastern England. The Barham Soil, buried beneath Anglian sediments, is recognised by a variety of large- and small-scale cryogenic features which developed in Cromerian sediments or were superimposed upon the Valley Farm Soil during the early Anglian. The Valley Farm Soil is rubified, mottled and contains substantial quantities of translocated clay. Originally attributed solely to temperate (Cromerian stage) pedogenesis, its stratigraphic status has changed over recent years as the age range of its Kesgrave Sands and Gravels parent material has been extended. Currently, the Valley Farm Soil is regarded as a complex stratigraphic unit with component soils developed on a series of different age surfaces, perhaps spanning cold and temperate intervals over more than a million years. Detailed micromorphological studies of the Valley Farm Soil on some of these surfaces have confirmed its variable pedological complexity. A number of theoretical and practical problems, however, need to be confronted and solved before its pedological record can be used routinely to provide an independent means of dating and reconstructing detailed palaeoenvironments.

Micromorphology of the buried Quaternary soil within Burchell's ‘Ebbsfleet Channel’, Kent

Thin section descriptions are used in conjunction with field and bulk analytical data to characterise and interpret the buried soil within Burchell’s ‘Ebbsfleet Channel’ deposits at Northfleet, Kent. The development of the buried soil can be separated into four phases beginning with deposition of the Middle Loam parent material. Phase 2 represents the main period of soil formation with calcite dissolution/reprecipitation, clay illuviation and bioturbation processes dominant. A change to wetter conditions and eventual re-establishment of the Ebbsfleet river (phase 3) led to translocation of silty clay, precipitation of iron/manganese oxides, soil truncation, deposition of the Upper Loam and disruption due to loading and/or slumping. Further modification took place after complete burial during phase 4, including partial recalcification of the soil by groundwaters or very recent post-excavation surface leachates. The exact age of the soil is uncertain, although phases 2 and 3 of this development sequence probably took place mainly during either the Ipswichian interglacial or an undefined post-Hoxnian/pre-Ipswichian temperate interval.

Vegetation and climate during warmer intervals in the Late Pleistocene of western and central Europe

Many warmer intervals occurred during the last interglacial-glacial cycle (130-10 ka) in Europe. The vegetational record shows several types of such intervals, among which the forest periods of the Eemian interglacial and the Amersfoort-Brørup interstadials of the Early Weichselian are of special interest. A series of map reconstructions is used to present some of the relevant vegetational and paleoclimatic characterizations. They represent two types of temperate intervals occurring in the Late Pleistocene in Europe, one with a rather uniform distribution of vegetation types, a warmer oceanic climate, and a high sea-level. The other type shows strong vegetation gradients (both north-south and east-west), a more continental climate, and a relatively low sea-level. Inland-ice probably persisted in the far north during this last type of interval. It is suggested that these two types of ‘interglacial’ occurred throughout the Pleistocene.

Farey systems of musical intonation

The distinction between consonant and dissonant intervals, represented in their just forms by frequency ratios expressible in low and high integer numbers respectively, is of prime importance in Western music. It is easy to tell just consonances from tempered ones on the basis of beat perception. Research by Vos & van Vianen (1985) with low‐number frequency‐ratio intervals has shown that beat detection can be predicted by the sum of the ratio numbers in the perfect (just) interval. We investigated the discrimination of perfect and imperfect (tempered) intervals with ratio numbers up to and including 16, thus mainly so‐called dissonances. Beat detection and discrimination are still possible, but are probably determined by other factors that simply the ratio‐numbers magnitude, such as the pattern of interferences in the sound stimulus. We investigated the practical possibilities of the high‐number ratio intervals by describing them as part of a Farey series of musical intervals. These investigations show th...