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Stump Cross Caverns house one of the important Pleistocene fossil bone beds of the UK. Yet, the dates of the Banwell Bone Cave Mammal Assemblage Zone (MAZ), to which these belong, have not yet been well constrained. Here we present new U-Th dates showing that Late-MIS 5 bison-reindeer-wolverine fauna was present in northern England at least as early as 91.9 ± 0.5 ka (the oldest date yet published); and that the Banwell Bone Cave fauna probably occupied the Yorkshire Dales from soon after ∼100 ka to 80 ka (late MIS 5c-early MIS 5a). This adds to the very small number of dates for this fauna, is somewhat older than the timing proposed in the literature, and suggests that the fauna arrived in NW Britain more than 5 kyr in advance of SW Britain. We also found an older bone bed dating from 175 to 172 ka, MIS 6d. This is only the second reported occurrence in the Yorkshire Dales of a fauna that pre-dates the Last Interglacial. Our results confirm that calcite deposition in this cave is precluded during interglacial peaks by local flooding, but at other times is similar to other caves of NW Europe. The oldest dates, on calcites from the uppermost levels, show dewatering by at least ∼430 ka (early MIS 11), adding to our understanding of the antiquity of the caves and the geomorphology of the region.

Dagmar Cave, Czech Republic, is the first locality in the Moravian Karst where sediments of Cromerian age have been discovered and it is the first locality with such a large number of species of molluscs of this age. It was originally a swallow hole initiated in the Neogene, which has since accumulated sediments. Basal sediments are palaeontologically-sterile stream boulders, originating from weathered Lower Carboniferous rock. After this, fossiliferous, loamy sediments were carried in from the entrance by streams and/or gravity. Molluscan and vertebrate assemblages, along with palynological remains, are indicative of interglacial conditions. Faunal analysis determined that this could only consist of one interglacial, either Cromerian III or IV. This is the first record of Middle Pleistocene molluscan fauna in the Moravian Karst. Palynology demonstrated a humid and thermophilic vegetation typical of a Cromerian interglacial, with forest, and probably water, and an open grassy/bushy area close to the cave. The age is constrained by a MIS 7 U-Th date (182 ka) on the calcite flowstone that overlies the interglacial material and underlies the palaeontologically more sterile upper sediments.

Recent studies of ancient bat guano deposits in the caves of Gunung Mulu National Park and Niah National Park, Sarawak, Malaysia, have resulted in noteworthy records of phosphate minerals from these environments, including variscite, nano-particulate silica, fluorapatite, and niter.

We demonstrate the utility of a multi-pronged approach to geomorphological studies. We show how the synthesis of results from 3-D imaging, varied geotechnical methods, and dating, reveals hitherto unknown features of a cave and of its sediment infill, and elucidates its geomorphological history. The Unicorn Cave (Einhornhohle, southern Harz Mountains, Germany), long famous for its cave bear, lion, and mammoth fossils, is a dry vadose trunk cave high above base level, characterized by large rooms connected by shallow passages, and filled with sediments up to 40 m thick. The sediment is an archive for natural and anthropogenic environmental change: the succession of river gravels, breccia, and silts and sands provides a paleo-geomorphic and climatic archive; while human artefacts from the Paleolithic period provide information about early settlement phases. Here we derive a detailed description of the Unicorn Cave and its sediment infill by utilising several sources: (i) We synthesise data from the literature into a comprehensive picture of the sediment infill; (ii) We present new geophysical measurements of the sediments in the large room Leibnizhalle, and discuss these new measurements in view of our older findings; (iii) We map the larger chambers with the photogrammetric structure-from-motion method to build three-dimensional models; (iv) We present new age estimates from speleothem samples in the cave and discuss them with other, published, age estimates. Finally we use our newly collected evidence to reconstruct the evolution of the entire Unicorn Cave (including the newly-revealed, not-yet-accessible passages and their pristine sediment infill, as yet undisturbed by fossil hunters). The main period of speleogenesis ended with base-level incision in the mid-Pleistocene; the deposition of basal river gravels, probably in the late Cromerian, was followed by a sequence of clays and loams, capped by speleothem at ~MIS 3; the dates suggest at least two bone beds (MIS 3, and MIS 5e), along with bone material older than MIS 7.

International audience; Three stalagmites, which grew in the high altitude (similar to 1800 m a.s.l.) Piani Eterni karst system (northern Italy), represent the longest speleothem palaeoclimate-environmental record from the southern Alps. U-Th dating shows their discontinuous formation during Marine Isotope Stage (MIS) 10, 8, 7d, 6 and 5d-b, with carbonate deposition prevented during both full interglacial and full glacial stages. Speleothem formation was inhibited during interglacial peaks because local base level rise, connected to global climate changes, caused the alluviation of the main epiphreatic levels of the cave system. Drainage of the hydrological pathways, caused by the progressive decrease of rainfall and the accumulation of a perennial snow pack, stopped carbonate deposition during glacials. Thus, Piani Eterni speleothems function as indicators of transitional interglacial to glacial (IG-G) climate periods over the last similar to 400 thousand years (kyrs). Analysis of delta O-18 and delta C-13 suggest that: i) seasonal snow melt occurred in these high altitude terrains during IG-G times, allowing meteoric water to efficiently penetrate the karst network; ii) soils were restored during MIS 5c-b, but absent during MIS 10, 8, 7d and 6 due to denudation of the karst surfaces; and iii) rainfall perturbations modulated the IG-G shifts in the southern Alps. Rainfall variation is connected to solar radiation changes at orbital timescales during MIS 5c-b, and mimics Dansgaard-Oeschger (DO) cycle variability during DO 23 and 22. DO cycle-like variability is also suspected during MIS 10, 8 and 6. The most important result is that, from a geochemical perspective, this study demonstrates that drivers of delta O-18 in southern alpine speleothems are similar to Mediterranean, Middle Eastern and Asian speleothems in that they are prevalently controlled by the rainfall amount effect. This contrasts with speleothem records from the more continental northern alpine sector where the air temperature effect on delta O-18 of precipitation dominates. (C) 2018 Elsevier Ltd. All rights reserved.

Za Hajovnou Cave in the Javoricko Karst (Moravia, Czech Republic) has a rich record of Middle Pleistocene, typical Holsteinian, flora and fauna dominated by bear Ursus deningeri. Sedimentological, geochemical, mineralogical, geophysical, palynological and zoopalaeontological analyses of the sediments along with U-Th dating of flowstones place the deposits into a numerical timeframe. The cave origin dates to a period before the mid-Miocene Badenian transgression. The oldest (fluvial) deposits are Lower Pleistocene, spanning the Brunhes/Matuyama boundary. The later (terrestrial) deposits range from Middle Pleistocene to Holocene. The most important result of U-Th dating is that the main (Holsteinian senso lato) fossil bed can be correlated with MIS 9. The lower fossil bed is probably MIS 11, and the upper fossil bed MIS 5e. This represents one of the still-relatively-few numerically dated Holsteinian sites, contradicts the Global Chronostratigraphical Correlation Table that places the Holsteinian only in MIS 11, and supports the concept that the Holsteinian is not a single unit and likely not confined to a single interglacial. (C) 2013 Elsevier Ltd and INQUA. All rights reserved.

A distinctive white sediment in the caves of Mulu, Sarawak, Borneo is a well-preserved tephra, representing a fluvially transported surface air-fall deposit, re-deposited inside the caves. We show that the tephra is not the Younger Toba Tephra, formerly considered as most likely. The shards are rod-shaped with elongate tubular vesicles; the largest grains ~ 170 μm in length; of rhyolitic composition; and 87Sr/86Sr ratio of 0.70426 ± 0.00001. U–Th dating of associated calcites suggest that the tephra was deposited before 125 ± 4 ka, and probably before 156 ± 2 ka. Grain size and distance from closest potential source suggests an eruption of VEI 7. Prevailing winds, grain size, thickness of deposit, location of potential sources, and Sr isotopic ratio limit the source to the Philippines. Comparisons with the literature give the best match geochemically with layer 1822 from Ku et al. (2009a), dated by ocean core stratigraphy to 189 ka. This tephra represents a rare terrestrial repository indicating a very substantial Plinian/Ultra-Plinian eruption that covered the Mulu region of Borneo with ash, a region that rarely receives tephra from even the largest known eruptions in the vicinity. It likely will be a valuable chronostratigraphic marker for sedimentary, palaeontological and archaeological studies.

Recent explorations in Cueva Charles Brewer, a large cave in a sandstone tepui, SE Venezuela, have revealed silica biospeleothems of unprecedented size and diversity. Study of one — a sub-spherical mass of opaline silica — reveals a complex, laminated internal structure consisting of three narrow dark bands alternating with two wider light bands. Uranium–thorium dating has produced 3 stratigraphically correct dates on the light bands from 298 ± 6 (MIS 9) to 390 ± 33 ka (MIS 11). U concentration is only 30–110 ppb. Initial234U/238U ratios are high and increase over time from 1.8 to 5.3. Growth rate is very low, the fastest, at 0.37 ± 0.23 mm/ka, in MIS 9. Trace element and heavy metal content of the dark bands is distinctly higher than that of the light bands. It is hypothesized that the dark and light bands correlate with drier/glacial and wetter/interglacial periods, respectively, and that this sample probably began to grow in MIS 13. The cave is in a region that straddles a regionally important ecotone: the speleothem isotopic and trace element variations may preserve a useful paleoclimatic signal. This is the first published suite of U–Th dates from a single silica speleothem and the longest Quaternary record for this region.

A stalagmite from northern Norway is dated with 12 thermal ionization mass spectrometry U-Th dates, and at least four separate growth periods are identified that correspond with marine isotope stages 9, 11, 13, and probably 15. The calcite is tested for isotopic equilibrium with the Hendy test. Oxygen isotope measurements on 231 subsamples on a vertical transect are used as a paleotemperature proxy. The detailed isotopic record from MIS 9 show apparent similarities to a Holocene record from the same cave, both in the climatic evolution and the overall temperatures: both show temperature oscillations changing from high-frequency, low-amplitude cycles in the beginning of the interglacial period to lower frequency, higher amplitude cycles in the later part of the interglacial period. The isotope record from MIS 11 shows a distinct isotopic event toward heavier values. The isotopic record together with the porous, humus-rich calcite are interpreted as indicating a warmer than present interglacial period with several episodes of heavy rainfall.

A stalagmite from Rana, northern Norway, dated by the TIMS uranium-series technique, yields records of stable oxygen and carbon isotopes covering the period from late marine oxygen isotope substages (MIS) 5e to 5a, that is, 123,350 to 73,300 yr ago. Rapid growth (∼46 μm/yr) between 123,350 and 119,500 yr ago reflects climatic conditions favorable for speleothem growth. This period is characterized by century- to millennial-scale oscillations in both stable isotope records, where both the absolute values and the isotope ranges are similar to Holocene and older samples from the region. From 119,500 to 107,700 yr ago, speleothem growth was slow (∼0.7 μm/yr), and between 107,700 and 73,300 yr ago growth is barely noticeable (0.07 μm/yr). During the period of slow growth the stable isotope records show an overall enrichment trend. The transition between rapid and slow growth rate occurring sometime between 119,500 and 107,700 yr ago is believed to reflect the termination of interglacial climate in this region. The absence of detritus and corrosion features in the slowly deposited calcite suggests that the valley outside the cave remained sufficiently ice free for speleothem growth to occur until at least 73,300 yr ago.

Speleothems (cave dripstones) are formed as a part of the meteoric water cycle and therefore vari ations in their growth rate and composition reflect environmental changes on the land surface above the cave. Since they are continental deposits, and possess a remarkably accurate dating potential, using TIMS U-series techniques, speleothems are important palaeoclimatic archives for the terrestrial environment, complementing the marine and ice-core records. The climatic proxies that can be deciphered from speleothems are growth rate, stable isotope composition (d18O, d13C), organic (humic) matter and trace element composition, as well as luminescent laminae, which may display annual rhythms. The nine papers in this special issue of The Holocene present the latest results in palaeoclimatic analysis from speleothems.

The speleothem delta function (SDF) provides a new transfer function between the d18O signal of speleothem calcite and surface ground temperature. The function is based on physical principles, relating d18O of the calcite to thermodynamic fractionation, and to the dripwater function, which in turn relates d18O of dripwaters to that of the local precipitation and thus to the modification of source water in relationship to the geographical position of the site. The SDF must be calibrated against at least two reliable and well-dated palaeotemperature points. The end product is a reconstruction of absolute cave and surface temperatures. The technique is tested using a Holocene speleothem from north Norway, SG93, dated by 12 TIMS U-Th dates. The reconstructed temperature curve is presented and compared with the GISP2 ice-core record and with the historic record. In both cases the correlation with SG93 is impressive, indicating the validity of the technique.

Two stalagmites from Anjohibe Cave have annual layers made up of inclusion-rich calcite over inclusion-free calcite or of darker aragonite over clear aragonite. Geochemical evidence indicates that the basal units are deposited slowly in the wet season and the upper units more rapidly in the dry season. For the period with rainfall and temperature data (ad 1951–1992), layer thickness correlates well with the Southern Oscillation Index (SOI), as well as rainfall, water surplus, and actual evapotranspiration (AET) at nearby Majunga. Com parison of the layer record for one stalagmite with 1866–1994 SOI data indicates that layer thickness correlates best with the frequency and intensity of warm, low-phase SO (El Niño) events, not with average SOI conditions. In addition, the 415-year layer thickness time-series from that speleothem agrees remarkably well with historical records of El Niño frequency, with Galápagos (Ecuador) coral records of sea-surface temperature in the eastern Pacific, and with accumulation rates on the Quelccaya Ice Cap of Peru, which are lower at times of high El Niño frequency.

In open-air sites, diagenetic alteration makes teeth difficult to analyze with electron spin resonance (ESR). Despite strong diagenetic alteration, three ungulate teeth from Pleistocene fluvial sediment in the open-air Paleolithic site at Attirampakkam, Tamil Nadu, India, were analyzed using standard and isochron ESR. Diagenetic alteration features in two teeth indicated rapid submergence in quiet saline to hypersaline water, following a short subaerial exposure, while the third remained constantly buried under reducing conditions. Geochemical signatures and ESR data all indicate that the teeth experienced at least three independent U uptake events during diagenesis, including two that occurred long after burial.