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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.

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.

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.

Teeth of Homotherium latidens recovered from late Pleistocene sediments, Kents Cavern, England have long been the source of controversy. H. latidens is conspicuously absent from other late Pleistocene cave deposits in Britain, and is widely thought to have been extirpated from the region during the isotope stage 10 glacial period. Here we present high spatial resolution analyses of fluorine and uranium uptake profiles in teeth of three species from the same cave. The H. latidens tooth is clearly distinguished from the unambiguously provenanced Late Pleistocene hyaena and Middle Pleistocene cave bear teeth. These results are consistent with the theory that the H. latidens teeth originated at an exogenous location, were probably transported to Kents Cavern as Palaeolithic trade goods, and were buried in Kents Cavern in Palaeolithic times.

article i nfo The Gomantong cave system of eastern Sabah, Malaysia, is well-known as an important site for harvesting edible bird-nests and, more recently, as a tourist attraction. Although the biology of the Gomantong system has been repeatedly studied, very little attention has been given to the geomorphology. Here, we report on the impact of geobiological modification in the development of the modern aspect of the cave, an important but little recognized feature of tropical caves. Basic modeling of the metabolic outputs from bats and birds (CO2, H2O, heat) reveals that post-speleogenetic biogenic corrosion can erode bedrock by between ~3.0 mm/ka (1 m/~300 ka) and ~4.6 mm/ka (1 m/~200 ka). Modeling at high densities of bats yields rates of corrosion of ~34 mm/ka (or 1 m/~30 ka). Sub-aerial corrosion creates a previously undescribed speleological feature, the apse-flute, which is semicircular in cross-section and ~80 cm wide. It is vertical regardless of rock properties, developing in parallel but apparently completely independently, and often unbroken from roof to floor. They end at a blind hemi-spherical top with no extraneous water source. Half-dome ceiling conch pockets are remnants of previous apse-fluting. Sub-cutaneous corrosion creates the floor-level guano notch formed by organic acid dissolution of bedrock in contact with guano. Speleogenetic assessment suggests that as much as 70-95% of the total volume of the modern cave may have been opened by direct subaerial biogenic dissolution and biogenically-induced collapse, and by sub-cutaneous removal of limestone, over a timescale of 1-2 Ma. © 2011 Elsevier B.V. All rights reserved.

A suite of distinctive freshwater subaerial phosphatic stromatolites is developed close to the northeastern entrance of Deer Cave, Gunung Mulu National Park, Sarawak, Borneo, in conditions of very low light but ample supply of nutrients from guano. These stromatolites are not particulate; they are composed of alternating layers of more porous and more dense amorphous hydroxylapatite. This biomineralization occurs as moulds of coccoid (the majority) and filamentous (less abundant) cyanobacteria. Mineralization occurs at a pH of ~ 7.0 in the extracellular sheaths and in micro-domains of varying carbonate content in the surrounding mucus of the biofilm. The most recent surfaces that are not yet strongly mineralized show still-living filamentous, coccoid and rod-shaped forms. Trace element composition shows enrichment in metal ions, especially Mn and Zn. The stromatolites are present as horizontal shelves arranged in series on a steep rock face that is vertically under a guano-laden shelf. The rock face undergoes active dissolution from acidic guano drainage water (e.g., pH of 2.43) and from aggressive rainwater from an overhead discharge. However, the rock surface under the stromatolite is protected while the rest of the cliff face is backcut, creating a hoodoo-like effect. The stromatolites are ~ 15–20 cm deep, ~ 4–7 cm thick, and of variable width, generally ~ 50 cm. Eventually, guano and biological detritus in the descending water film lodge in the lee of the stromatolite lip, causing local acidification and erosion of stromatolite and rock on the underside of the ledge. A dynamic equilibrium is established between upward accretion of the fresh surface and destruction at the base such that the base of the stromatolite does not reflect the date of its inception and the stromatolite climbs up the wall.

A distinctive suite of small-scale erosional forms that are oriented towards the light occur close to the entrance of Cueva Charles Brewer, a large cave in a sandstone tepui, in SE Venezuela. These are the third example of photokarren ever studied in the world, the other two being from Borneo and Ireland. They are the only photokarren ever described from sandstone, and the only example from a non-carbonate environment. The host rock is a poorly-lithified unit of the Precambrian quartz arenite of the Roraima Supergroup. The forms are all oriented towards the light at 30° regardless of rock surface orientation. The primary (negative) erosional form is the tube. Coalescence of tubes results in the positive remnant forms of rods, pinnacles, and cones. The final stage is a bumpy, wavy surface of degraded cones. The size of the features varies with erosion rate, and details of the form vary with development stage. The main population averages 4.4 cm in depth, with 55% of the surface eroded. This is divided into 10% tubes, 70% rods, 10% cones, 5% linear valley and 5% wavy lowland. The micro-ecosystem includes many bacteria, diatoms, red algae, green algae, liverworts, and oribatid mites, but, surprisingly, no cyanobacteria. The presence of a surface biofilm inside the forms but not on the remnant rock surface and, in the non-degraded forms, the direct relationship of biomass with depth suggests that biological activity is the dominant control on development. In addition, direct bacterial corrosion was noted. These same features occur to varying extents in the photokarren of Borneo and Ireland, and the model for development that we present provides a unifying theory for all photokarren. (This study also includes the first published petrographic analysis of uppermost unit of the Mataui Formation).

article The microclimatic effect of bats roosting in bell holes (blind vertical cylindrical cavities in cave roofs) in Runaway Bay Caves, Jamaica, was measured and the potential impact of their metabolism on dissolution modelled. Rock temperature measurements showed that bell holes with bats get significantly hotter than those without bats during bat roosting periods (by an average of 1.1 °C). The relationship is clearest for bell holes with more than about 300 g aggregate bat body mass and for bell holes that are moderately wide and deep, of W:D ratio between 0.8 and 1.6. Measurement of temperature decay after abandonment showed that rock temperature returns to normal each day during bat foraging periods. Metabolic activity from a typical population of 400 g bat (10 individuals) yields 41 g of CO2, 417.6 kJ of heat, and 35.6 g of H2O in each 18 hour roost period, and could produce a water film of ~0.44 mm, that is saturated with CO2 at ~5%. The resultant rock dissolution is estimated at ~0.005 cm

Although coupled 230Th/234U–ESR analyses have become routine for dating teeth, they have never been used for corals. While the ESR age depends on, and requires assumptions about, the time-averaged cosmic dose rate, D ¯ cos ( t ) , 230Th/234U dates do not. Since D ¯ cos ( t ) received by corals depends on the attenuation by any intervening material, D ¯ cos ( t ) response reflects changing water depths and sediment cover. By coupling the two methods, one can determine the age and a unique D ¯ cos , coupled ( t ) simultaneously. From a coral's water depth and sedimentary history as predicted by a given sealevel curve, one can predict D ¯ cos , sealevel ( t ) . If D ¯ cos , coupled ( t ) agrees well with D ¯ cos , sealevel ( t ) , this provides independent validation for the curve used to build D ¯ cos , sealevel ( t ) . For six corals dated at 7–128 ka from Florida Platform reef crests, the sealevel curve by Waelbroeck et al. [2002. Sea-level and deep water temperature changes derived from benthonic foraminifera isotopic records. Quat. Sci. Rev. 21, 295–305] predicted their D ¯ cos , coupled ( t ) values as well as, or better than, the SPECMAP sealevel curve. Where a whole reef can be sampled over a transect, a precise test for sealevel curves could be developed.

The PP10 stalagmite from Poleva Cave provides a Late Pleistocene and Holocene isotopic record characteristic for the SW of Romania, a sub-Mediterranean climatic region. The speleothem was dated by eight TIMS and one alpha U-series dates which showed that it was precipitated between ∼75 ka and ∼2 ka with at least two hiatuses. The basal sector of the stalagmite showed a slow-growing regime of ∼0.26 cm/ka, while the upper one grew relatively fast with about 5 cm/ka. The temporal resolution for the isotopic sampling is thus ∼2 ka/sample for the lower sector, and ∼150 years/sample for the upper one. The relationship between δ 18 O and temperature was found positive. The isotopic record of the lower sector shows two marked cold intervals during ∼67 and 58 ka and ∼40–35 ka, respectively, which correlate well with the Villars and Soreq records. The upper sector record is so far the most detailed Holocene isotopic record in Romania and the only one available for the regions located at the exterior of the Carpathians Range. The signal shows a gradual warming after the GS1 event punctuated by several cold events at ∼8, 7.2 and 4.2 ka and also by warm oscillations centered at about 5.2 and 3.3 ka. The results seem to indicate that if the North-Atlantic firstorder signals may extend well to the south-eastern Europe, their amplitude and general trend may be diminished by the interferences with the Mediterranean circulation.

Early human footprints are rare in the fossil record. A survey of the literature reveals very few well documented and dated cases. Here, we report the first clear Homo neanderthalensis footprint. It was found in Vârtop Cave, Romania. The individual stepped into calcareous mud that later hardened. The 22 cm long print suggests a body height of ∼1.46 m; a gap of 1.6 cm marks the separation of big and second toes. The date of the footprint is constrained by three coeval dates of ∼62 kyr on sub-samples from the basal layer of a nearby stalagmite that grew on top of the layer of calc-tufa covering the footprint. The lower constraint is a poorly constrained uranium (U)–thorium (Th) isochron date of ∼97 kyr on the calc-tufa layer in which the footprint is embedded. Thus, the Vârtop Cave individual lived in Romania sometime before 62 kyr, long before the appearance of Homo sapiens in Central and Eastern Europe, the earliest records of which date from only ∼35 kyr. To our knowledge, this is the first recognised and dated Homo neanderthalensis footprint.

High-precision TIMS U-series dates and continuous stable oxygen and carbon isotope profiles of a 4000 year stalagmite record from Rana, northern Norway, are presented and compared with data from two other speleothems from the same cave. The dating results yield ages from 3875 ^ 34 to 296 ^ 3 years before AD2000, with 2s errors from 0.5 to 1%. The overall growth rate is 35 mm/ka, corresponding to a temporal resolution of 29 years/mm. The stalagmite is tested for isotopic equilibrium conditions, where all ‘Hendy’ tests, except one, indicate isotopic equilibrium or quasi equilibrium deposition. Both the stable oxygen and carbon isotope records reveal a strong and abrupt enrichment in the near-top measurements. This corresponds in time to the opening of a second cave entrance in the late 1960s, which caused changes in the cave air circulation. The stable oxygen isotope signal is enriched compared to the modern value over the last 300 years, indicating a negative response to temperature changes. Likewise, the stable carbon isotope record is enriched in this period. However, both of the stable isotope records are shown to be significantly enriched compared to the isotope ranges displayed by other stalagmites in the same cave, and this questions the reliability of the proxy records derived from the presented stalagmite. Still, a general good correspondence of large scale fluctuations is found between the three stable oxygen isotope records from this cave. The stable carbon isotope records show large variations within the cave and are believed to be governed by soil-zone conditions, percolation pathways and possibly driprates. q 2001 Elsevier Science B.V. All rights reserved.

Micron level resolution is required to image tightly spaced annual bands in speleothems. These same bands must be viewed over several millimeters and sometimes centimeters in order to ensure continuity. We report luminescence imaging results from several speleothem specimens using a novel confocal scanning laser macroscope instrument. The macroscope can non-destructively image specimens as large as 7.5×7.5 cm using reflected light and photoluminescence with a 10 μm lateral resolution in under 10 s. A high-resolution version of the macroscope can image specimens up to 1–2 cm in size with lateral resolutions ranging from 1 to 2 μm depending upon the laser scan lens utilized. The combination of both these instruments allows for entire specimens to be imaged even beyond 7.5×7.5 cm fields of view via tiling. Confocal imaging improves overall resolution of the instrument by eliminating light originating from outside the focal plane which tends to blur the image. High-contrast, crisp images are achieved in this way. We show photoluminescence imaging results for speleothem specimens where emphasis is placed on resolving to the level of annual bands.

A well-preserved, submerged, in situ fossil reef tract lies offshore of the southeast Florida carbonate margin in the Florida Keys. Cores in two transects enabled reconstruction of reef stratigraphy and paleoenvironments, paleo water depths, and paleo sea-levels. Because Florida is tectonically stable, the elevation data required correction only for the known, minor subsidence rate. Twenty eight pristine aragonitic corals were dated via high-precision TIMS U-series methods to produce a comprehensive late Pleistocene and early Holocene geochronology. The Pleistocene section of the fossil reef includes a thick section of Substage 5a reef growth recorded from ≈−15 to −11 m MSL, spanning an age range of 86.2–80.9 ka. Paleoenvironmental reconstruction, local water quality constraints, and elevations of concurrent Bahamian speleothem growth combine to limit sea-level to ≈−9.0 m MSL at ≈83 ka. This coincides, unlagged, with the 82 ka 65°N July insolation peak: the absence of any lag suggests that the earlier peak in obliquity at 92 ka also controls paleoclimate and sea-level. A below-present sea-level estimate for Substage 5a from the Florida fossil reef data coincides more closely with uplift-corrected reef data estimates of −15 to −13 m MSL from tectonic margins such as Barbados and Haiti, than with higher than present sea levels derived from detrital corals from Bermuda and the U.S. Atlantic Coastal Plain. The best TIMS dates on corals and speleothem constraining sea level combine to produce a new regional sea-level curve for the Atlantic-Caribbean region for late isotope stage 5 and early stage 4.

The dating of sea level events by a method independent of orbital tuning techniques and the marine foraminiferal isotopic record provides a test of both the dating of the marine record and the strength and nature of the relationship between climatic change, sea level change and Milankovitch cycles. Dating of fossil corals and submerged speleothem provides such independent information. Results of thermal ionization mass spectrometric U-series dating on layers of flowstone speleothem from Lucayan Caverns, Grand Bahama Island indicate that multiple sea level events have passed through a depth of −10 to −15 m below modern sea level during the last 300,000 years. These data are used to constrain the magnitude and timing of sea-level fluctuations during the late Pleistocene. The new sea level curve constructed from these data correlates closely with the marine isotopic record: sea level peaks occurred at around 233, 215, 125 and 100 ka BP. There is no evidence at the depth from which this speleothem was retrieved of any high sea stands at 195 or 80 ka corresponding to the foraminiferal 7a and 5a oxygen isotope peaks. There is also no evidence of a double rise around the 125 ka (5e) peak, although such an oscillation could have occurred above −10 m leaving no record in the Lucayan Caverns speleothem.