Latest Quaternary papers

Friday, 11 April 2014
Boreas

Late Quaternary (Marine Isotope Stage 3 to Recent) sedimentary evolution of the Basque shelf (southern Bay of Biscay)

Late Quaternary (MIS 3 to Recent) oceanographic evolution of the Basque shelf has been analysed for the first time based on the sedimentological analysis of three cores obtained from the middle and outer shelves. The cores are located in two interfluves separated by the San Sebastian canyon. The variability of the percentage of the planktonic foraminifera species Neogloboquadrina pachyderma sin. and of δ18Obull allowed us to identify the influence of colder and warmer waters in the Basque shelf during the late Quaternary. From ∼56 cal. ka BP to the end of the Last Glacial Maximum (19 cal. ka BP) the sedimentary record shows a decreasing trend in the mean grain size that correlates with the eustatic sea-level fall. The last Deglaciation (19–11.5 cal. ka BP) is characterized by a sea-level rise that produced an important hiatus in the western outer shelf. During the Holocene, the middle and outer shelves present different behaviours. From 11.5 to 6.7 cal. ka BP, in the outer shelf the sea-level rise that started during the Deglaciation produced a hiatus, whereas in the middle shelf the sedimentary succession records the presence of warm to temperate waters. Between 6.7–4.9 cal. ka BP, the entrance of cold surface water-masses that only affected the middle shelf has been identified, and temperate to warm waters occurred in the outer shelf. The cold surface water-masses retreated during 4.9–4.3 cal. ka BP in the middle shelf. Finally, from 4.3 cal. ka BP to Recent, the middle shelf registers a hiatus due to sea-level stabilization after a generalized transgression, synchronous to a decrease in the energy of the water-masses in the outer shelf. In conclusion, the environmental changes detected in the Basque shelf are attributed to both regional and eustatic sea-level changes.

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Tuesday, 08 April 2014
Boreas

Palaeoecological, archaeological and historical data and the making of Devon landscapes. I. The Blackdown Hills

This paper presents the first systematic study of the vegetation history of a range of low hills in SW England, UK, lying between more researched fenlands and uplands. After the palaeoecological sites were located bespoke archaeological, historical and documentary studies of the surrounding landscape were undertaken specifically to inform palynological interpretation at each site. The region has a distinctive archaeology with late Mesolithic tool scatters, some evidence of early Neolithic agriculture, many Bronze Age funerary monuments and Romano-British iron-working. Historical studies have suggested that the present landscape pattern is largely early Medieval. However, the pollen evidence suggests a significantly different Holocene vegetation history in comparison with other areas in lowland England, with evidence of incomplete forest clearance in later-Prehistory (Bronze−Iron Age). Woodland persistence on steep, but poorly drained, slopes, was probably due to the unsuitability of these areas for mixed farming. Instead they may have been under woodland management (e.g. coppicing) associated with the iron-working industry. Data from two of the sites also suggest that later Iron Age and Romano-British impact may have been geographically restricted. The documented Medieval land management that maintained the patchwork of small fields, woods and heathlands had its origins in later Prehistory, but there is also evidence of landscape change in the 6th–9th centuries AD. We conclude that the Blackdown Hills area was one of many ‘distinctive subregions’, which due to a combination of edaphic, topographic and cultural factors could qualify as an eco-cultural region or ‘pays’. It is argued that the use of such eco-culturally distinctive regions or pays can provide a spatial and archaeological framework for palaeoecology, which has implications for landscape research, designation and heritage management.

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Friday, 04 April 2014
Earth and Planetary Science News

he influence of pH on organovermiculite structure stability

Daniela Plachá, Gražyna Simha Martynková, Alicja Bachmatiuk, Pavlína Peikertová, Jana Seidlerová, Mark H. Rümmeli

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Friday, 04 April 2014
Earth and Planetary Science News

Lead isotope signatures of Kerguelen plume-derived olivine-hosted melt inclusions: Constraints on the ocean island basalt petrogenesis

Anastassia Y. Borisova, François Faure, Etienne Deloule, Michel Grégoire, Frédéric Béjina, Philippe de Parseval, Jean-Luc Devidal

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Friday, 04 April 2014
Earth and Planetary Science News

Outlining of high quality coking coal by Concentration-Volume fractal Model and Turning Bands Simulation in East-Parvadeh Coal Deposit, Central Iran

Peyman Afzal, Seyed Hosein Alhoseini, Behzad Tokhmechi, Dariush Kaveh Ahangaran, Amir Bijan Yasrebi, Naser Madani, Andrew Wetherelt

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Friday, 04 April 2014
Earth and Planetary Science News

Revised conodont-based integrated high-resolution timescale for the Changhsingian Stage and end-Permian extinction interval at the Meishan sections, South China

Dong-xun Yuan, Shu-zhong Shen, Charles M. Henderson, Jun Chen, Hua Zhang, Hong-zhen Feng

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Friday, 04 April 2014
Earth and Planetary Science News

Shale Characteristics in the Southeastern Ordos Basin, China: Implications for Hydrocarbon Accumulation Conditions and the Potential of Continental Shales

Xuan Tang, Jinchuan Zhang, Xiangzeng Wang, Bingsong Yu, Wenlong Ding, Jinyu Xiong, Yiting Yang, Long Wang, Chao Yang

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Friday, 04 April 2014
Earth and Planetary Science News

Sutures modified by silver-loaded montmorillonite with antibacterial properties

Gao-Fei Cao, Yan Sun, Jian-Gang Chen, Li-Ping Song, Jin-Qiang Jiang, Zhao-Tie Liu, Zhong-Wen Liu

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Friday, 04 April 2014
Earth and Planetary Science News

The campsite dykes: A window into the early post-solidification history of the Skaergaard Intrusion, East Greenland

Marian B. Holness, Chris Richardson, Jens C.Ø. Andersen

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Friday, 04 April 2014
Earth and Planetary Science News

The protective effect of layered double hydroxide against damage to DNA induced by heavy metals

Ping-xiao Wu, Wen Li, Ya-jie Zhu, Yi-ni Tang, Neng-wu Zhu, Chu-ling Guo

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Friday, 04 April 2014
Earth and Planetary Science News

Thermal maturity evaluation from inertinites by Raman spectroscopy: The ‘RaMM’ technique

Ronald W.T. Wilkins, Roger Boudou, Neil Sherwood, Xianming Xiao

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Tuesday, 01 April 2014
Boreas

Biosedimentary record of postglacial coastal dynamics: high-resolution sequence stratigraphy from the northern Tuscan coast (Italy)

Integrating analysis of the benthic palaeoecological record with multivariate ordination techniques represents a powerful synergy able to provide an improved characterization of coastal depositional facies in a sequence stratigraphical perspective. Through quantitative analysis of benthic foraminifer, ostracod and mollusc associations from the postglacial succession of Core M3 (Arno coastal plain, Tuscany, Italy), and application of detrended correspondence analysis (DCA) to the mollusc sub-data set, we offer a refined picture of stratigraphical variations in faunal content from a paralic depositional setting, and reconstruct the palaeoenvironmental gradients that account for such variations. Despite distinct ecological behaviours, and taphonomic and sedimentological constraints, a strong ecological control on meio- and macrofaunal biofacies and taxa turnover is documented across the study succession. Amongst all possible mechanisms that may play a role in ‘shaping’ fossil distribution, the ecological signal driven by salinity represents the most prominent factor controlling the composition of fossil associations in the cored succession. Molluscs can even provide outstanding quantitative estimates of palaeosalinity along the sampled core. When plotted stratigraphically, the three fossil sub-data sets show consistent patterns of vertical evolution that enable prompt identification of the key surfaces for sequence stratigraphical interpretation in otherwise lithologically indistinguishable deposits. The concomitant maximum richness of species with strong marine affinity, paralleled by the highest DCA salinity estimates, allows recognition of the maximum flooding zone, dated to ∼7.7 cal. ka BP, within a homogeneous succession of outer lagoon clays. These clays are sandwiched between early transgressive, swamp to inner lagoon deposits and overlying prograding coastal−alluvial plain facies.

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Tuesday, 25 March 2014
Boreas

The Last Permafrost Maximum (LPM) map of the Northern Hemisphere: permafrost extent and mean annual air temperatures, 25–17 ka BP

This paper accompanies a map that shows the extent of permafrost in the Northern Hemisphere between 25 and 17 thousand years ago. The map is based upon existing archival data, common throughout the Northern Hemisphere, that include ice-wedge pseudomorphs, sand wedges and large cryoturbations. Where possible, a distinction is made between areas with continuous permafrost and areas where permafrost is either spatially discontinuous or sporadic. The associated mean annual palaeo-temperatures that are inferred on the basis of present-day analogues increase understanding of the possible changes in permafrost extent that might accompany current global warming trends. Areas with relict permafrost and areas that were formerly exposed due to lower sea level (submarine permafrost) are also mapped. Mapping is mostly limited to lowland regions (areas approximately <1000 m a.s.l.). Striking features that appear from the map are (i) the narrow permafrost zone in North America, which contrasts with the broader LPM permafrost zone in Eurasia (that may be related to different snow thickness or vegetation cover), (ii) the zonal extent of former LPM permafrost (that may reflect sea-ice distribution), which contrasts with the present-day pattern of permafrost extent (especially in Eurasia) and (iii) the relatively narrow zones of LPM discontinuous permafrost (that may indicate strong temperature gradients).

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Friday, 21 March 2014
Journal of Quaternary Science

Dating the onset of Lower Tagus River terrace formation using electron spin resonance

In the Western Iberian Peninsula, staircases of fluvial terraces have been the subject of several recent studies. In particular, many recent publications have focused on the Quaternary fluvial chronostratigraphy of the Lower Tagus Basin. However, there are still doubts with respect to the timing of the first incision into the late Tertiary basin-fill deposits, their upper part already recording a fluvial environment (‘basin inversion’), which was the start of terrace formation. This is because most dating methods are ineffective for this type of deposit (generally without organic and/or volcanic materials). In the last 10 years, new dating methods such as electron spin resonance (ESR) applied to sedimentary quartz now facilitate more accurate chronologies. This paper presents the results of the ESR dating of the older terraces of the lower Tagus Basin, Portugal, with extrapolation on the age of early drainage network evolution. According the results, the oldest fluvial terrace was formed around 900 ka, so the origination of the Portuguese Tagus River terrace system can be attributed to the final part of the Early Pleistocene.

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Friday, 21 March 2014
Journal of Quaternary Science

Geological evidence for an unusually large tsunami on the Pacific coast of Aomori, northern Japan

To assess long-term tsunami inundation history, we studied a wetland on the Pacific coast of Aomori, Japan, at the northern end of the Japan Trench. We found five sand sheets interbedded in freshwater mud and peat, three of which contained brackish diatoms indicating deposition by marine inundation. We identified the youngest sand sheet, deposited AD 1480–1770, as a tsunami deposit based on its lateral extent (>1 km) from the shoreline at the time of its deposition. Although this area has been struck by many tsunamis generated by earthquakes along the Japan Trench as well as along the Kuril and Peru–Chile trenches, no tsunami recorded at least in the past 120 years has inundated the coast as far inland as this tsunami deposit is distributed. We therefore infer that it was deposited by an unusually large tsunami. Historical and geological evidence for tsunamis in north-east Japan suggests that possible sources are the AD 1611 Keicho earthquake along the Japan Trench, a 17th-century earthquake along the Kuril Trench, or an unknown large earthquake.

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Friday, 21 March 2014
Journal of Quaternary Science

Environmental dynamics and luminescence chronology from the Orlovat loess–palaeosol sequence (Vojvodina, northern Serbia)

The Carpathian Basin contains some of the best preserved loess deposits in Europe, including some of the continent's longest and best resolved climate records. Large areas of the basin have been intensively investigated in recent years, although deposits in the east remain largely unstudied, despite considerable regional variation in climate records. Here we discuss the sedimentary record exposed in the Orlovat brickyard using detailed litho- and pedo-stratigraphic, enviromagnetic parameters and luminescence dating. The results show an atypical Late Pleistocene succession for the Carpathian Basin. Notably, the normally widespread pedocomplex V-L1S1 is missing. This contrasts with other parts of the sequence, which appear highly resolved, such as the thicker pedocomplex V-S1 and the detailed transitions between modern pedocomplexes V-S0 and the last glacial loess unit V-L1. The luminescence chronology demonstrates a lack of intensive pedogenesis during the Early Holocene and raises an important general question about the beginning of Holocene soil formation in the region. The later Holocene soil formation adds to a growing body of evidence that suggests more complex terrestrial responses of climate to global climate change. This evidence weakens the validity of previously generalized direct stratigraphic correlations between regional terrestrial environmental archives, and global marine and ice core records.

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Friday, 21 March 2014
Journal of Quaternary Science

A Late Pleistocene record of climate and environmental change from the northern and southern Kelabit Highlands of Sarawak, Malaysian Borneo

A late Pleistocene vegetation record is presented, using multi-proxy analysis from three palaeochannels in the northern (Bario) and southern (Pa'Dalih) Kelabit Highlands of Sarawak, Malaysian Borneo. Before 50 000 cal a BP and until ∼47 700 cal a BP [marine isotope stage 3 (MIS3)], two of the sites were probably being influenced by energetic fluvial deposition, possibly associated with strong seasonality. Fluvial activity declines between 47 700 and 30 000 cal a BP (MIS3), and may be associated with a reduction in seasonality with overall stability in precipitation. The pollen record between 47 700 and 30 000 cal a BP generally shows much higher representation of upper-montane taxa compared with the Holocene, indicating often significantly reduced temperatures. After 35 000–30 000 cal a BP and until the mid-Holocene, hiatuses appear in two of the records, which could be linked to fluvial down-cutting during the late/mid Holocene. Despite the jump in ages, a pronounced representation of Ericaceae and upper-montane taxa, represented both at Bario and at Pa'Dalih, corresponds to a further lowering of temperatures during the Last Glacial Maximum (MIS2). Thick charcoal bands in the PDH 210 record also suggest periods of extreme aridity between 30 200 and 12 700 cal a BP. This is followed by energetic fluvial deposition of sands and gravels, and may reflect a significant increase in seasonality.

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Friday, 21 March 2014
Journal of Quaternary Science

Climatic influence upon early to mid-Holocene fire regimes within temperate woodlands: a multi-proxy reconstruction from the New Forest, southern England

A combined pollen, charcoal and climatic record is presented from Cranes Moor, southern England, covering the period c. 10 500–5850 cal a BP. It is shown that the occurrence of burning is closely related to natural processes, including prevailing climatic conditions and vegetation composition. These burning events are often linked to an increase in the summer moisture deficit, implying that the timing of burning events is linked to periods of warmer/drier climate during the Holocene Thermal Maximum (c. 11 000–5000 cal a BP). These events play an important role in the vegetation composition and succession around the site. The nature of the burning recorded at the site shows strong similarities with other records from northern Europe. This study throws caution on suggestions that fire in the Holocene record from areas such as the British Isles is linked only to human activity, and enhances the possibility that natural fire incidence played an important role in natural woodland structure dynamics.

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Tuesday, 18 March 2014
Earth and Planetary Science News

Cyclic direct shear behaviours of frozen soil-structure interface under constant normal stiffness condition

Lianzhen Zhao, Ping Yang, J.G. Wang, Lai-Chang Zhang

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Tuesday, 18 March 2014
Earth and Planetary Science News

Modelling the friction of ice

In Press, Accepted Manuscript, Available online 13 March 2014 Lasse Makkonen, Maria Tikanmäki

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