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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.

The Gomantong cave system, Kinabatangan, Sabah (Malaysia) hosts one of the largest bat colonies known from north Borneo. The nightly exodus of Chaerophon plicatus from this site is an economically valuable tourist attraction, and must impose significant controls on the regional ecology. Monitoring ecosystem health requires monitoring bat population size, but no quantitative assessments for the Gomantong colony are available in the literature. Traditional censusing techniques (based on packing density and roost area or on roost exodus counts) yield notoriously unreliable results. Here we have applied innovative image analysis and counting techniques to videographic, photographic and terrestrial laser scanning data obtained in July 2012. The colony exits in a consistent stream along a narrow exit trajectory. The laser scanning of the large cave entrance allowed precise measurement of bat position. Video data provided 0.02-second time resolution. Average flight speed was calculated (10.38 ± 0.85 m/sec), bat ...

High resolution terrestrial laser scanning (TLS) within the Simud Hitam Cave, Gomantong, has proven successful at discriminating the nests of black-nest swiftlets from roosting bats in high, inaccessible locations. TLS data were imported into ArcGIS software, allowing for semi-automated counting of nests based on resolved geometry and laser return intensity. Nest resolution and counting accuracy was better than 2%. Spatial analysis of nest locations has established a maximum packing density of 268 nests/m2 in optimum locations, which correspond to roof slopes of >20 degrees. Co-occurring Rhinolophid bats roost adjacent to, but not within nest locations, preferring roof surfaces close to horizontal.

A novel aquatic drone ventured into highly acidic waters to test the feasibility of remotely exploring and surveying hazardous volcanic lakes.

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.

The laser ablation ICP–MS transect of a speleothem from GB Cave, close to Charterhouse, Mendip Hills, UK, records Pb variations over the past 5 ka. The speleothem record correlates well with the known historical record of lead mining in the district, the principal features of which include: the Roman lead mining peak; the Dark Ages cessation; gradual, episodic revival up to the late 16th century peak; the 17th century collapse and subsequent recovery; and the final short-lived burst at the end of the 19th century. This correlation supports the assumption that the pre-Roman lead record also derives from local mining. Thus, this record is the first example of quantifying ancient human mining activity through trace element signature of a speleothem. This record also provides the first solid evidence of significant pre-Roman mining activity in the Charterhouse region, and the first solid dating of that activity. This pre-Roman mining can be divided into three main peaks dated to 1800–1500 bc, 1100–800 bc and 350–0 bc.

Several caves in Devon, England, have been noted for extensive cracking of substantial flowstone floors. Conjectural explanations have included earthquake damage, local shock damage from collapsing cave passages, hydraulic pressure, and cryogenic processes. Here we present a theoretical model to demonstrate that frost-heaving and fracture of flowstone floors that overlie wet sediments is both a feasible and likely consequence of unidirectional air flow or cold-air ponding in caves, and argue that this is the most likely mechanism for flowstone cracking in caves located in Pleistocene periglacial environments outside of tectonically active regions. Modeled parameters for a main passage in Kents Cavern, Devon, demonstrate that 1 to 6 months of -10 to -15° C air flow at very modest velocities will result in freezing of 1 to 3 m of saturated sediment fill. The resultant frost heave increases with passage width and depth of frozen sediments. In the most conservative estimate, freezing over one winter season of 2 m of sediment in a 6-m wide passage could fracture flowstone floors up to ~13 cm thick, rising to ~23 cm in a 12-m wide passage. Natural flaws in the flowstone increase the thickness that could be shattered. These numbers are quite consistent with the field evidence.

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 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.

Most last interglacial (MIS 5.5) coral reef deposits in the Caribbean are emergent. However, in St. Croix, these are found mainly at depth, underneath Holocene material and confirmed by TIMS U–Th dated corals from eight cores through Holocene reefs. The only emergent MIS 5.5 marine deposit peaks at +1.5 m MSL at the northwestern end of the island. The Late Pleistocene surface decreases at least 9.25 m (based on reef crest elevations) in elevation over 15 km along a 0.62 m/km eastward (alongshore) slope. Neither differential erosion nor a naturally sloping deposit is likely, thus the directional elevation decrease requires the influence of tectonic processes. Platform tilting or differential subsidence increasing in rate to the east probably operated both during and since the last interglacial and created progressively greater accommodation space for increasingly thicker overlying Holocene reefs in an eastward direction. Rates of subsidence since MIS 5.5 increase from west to east, from 0.02 mm/year to 0.1 mm/year, assuming a MIS 5.5 +6-m sea level and +4 m initial reef elevation. St. Croix’s association with extensional shelf faulting from the northern part of the Virgin Islands Basin, the Anegada Fault to the east and the Puerto Rico Trench to the north may be significant in terms of identifying mechanisms for, or past events resulting in, directional tilting. Identification of differential elevations of MIS 5.5 reefs adds substantially to the information on Late Quaternary tectonism of the area.

The ‘breccia’ stratum from Kents (we follow local tradition in using the form ‘Kents’, without an apostrophe) Cavern, England, has been well known for its rich yield of cave-bear material since excavations began in the mid-19th century. Recent work has established that the bears are of latest MIS 12 or earliest MIS 11 age. A life table based on a collection of 67 molariform teeth is consistent with the use of the cave as a hibernaculum. Univariate and morphological assessment of the teeth shows an unusual range of primitive and more derived characters. Multivariate morphometric analysis of cave-bear teeth from the site demonstrates that these animals, while currently assignable to Ursus deningeri sensu lato, are nevertheless morphologically distinct and not simply late deningeri on a hypothetical chronospecific continuum.

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.

Joyce Lundberg1 and Donald A. McFarlane2 Figure 1. Location of Niah Caves, Sarawak, Malaysia

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).

We present 23 new thermal ionization mass spectrometric U-Th dates for Victoria Cave, North Yorkshire, UK. Victoria Cave underwent repeated glaciation during the late Pleistocene and contains one of the longest Quaternary cave sequences in Britain. The dates reveal that speleothem formation began beyond the range of the dating technique (before 600 ka). Finite reproducible dates of 490 −9/+10 ka confirm speleothem deposition during marine isotope stage (MIS) 13, the oldest date we know of for this part of Britain. Further speleothem formation was dated to MIS 11, MIS 9, MIS 7, and MIS 5. The results are the basis for a new chronology of Quaternary events for the cave and greatly enhance our understanding of the factors affecting the formation of the sedimentary sequence. Cyclical climatic and environmental change throughout the late Pleistocene triggered cyclical sedimentation events in the cave. All the interglacial periods show calcite deposition but with growth phases postdating the warmest events of MIS 11 and MIS 5e. The position of the cave halfway up the side of a glacial trough resulted in very distinctive sediment during the more extreme glacial maxima: ice-dammed lakes formed inside the cave and deposited varve-like clay rhythmites. The dates inferred for these deposits suggest that this locality underwent significant glaciation during MIS 12, MIS 10, MIS 6, and MIS 2, and that the ice was warm based. The absence of rhythmites during MIS 8 suggests minimal ice cover at that time. This is the most complete record for glacial events in the region; it is the only site where successive glacial maxima can be identified and dated. The record of large faunal remains indicates that the cave was open to the surface, only for relatively short times, during MIS 13, MIS 12, MIS 5e, the Late Glacial Interstadial, and parts of the Holocene. It is inferred that at other times the cave was closed because scree formation blocked the entrance. The record of vertebrate remains is therefore controlled by geomorphological processes. The deteriorating state of this unprotected site remains a cause for concern.

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.

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

Mid-Holocene age fossil-fringing reefs occur along the tectonically stable north coast of Java, Indonesia, presenting an opportunity for sea level and paleoclimate reconstruction. The fossil reef at Point Teluk Awur, near Jepara, Central Java, contains two directly superposed horizons of Porites lobata microatolls. Corals in the lower horizon, 80 cm above modern sea level, yielded Uranium series dates of 7090 ± 90 year BP, while corals in the upper horizon at 1.5 m grew at 6960 ± 60 year BP. These dates match the transgressive phase of regional sea-level curves, but suggest a mid-Holocene highstand somewhat older than that recorded on mid-Pacific islands. Paleotemperature was calibrated using Sr/Ca and δ18O values of a modern P. lobata coral and the locally measured sea surface temperature (SST), yielding SST–Sr/Ca and SST–δ18O calibration equations [T Sr/Ca = 91.03–7.35(Sr/Ca) and $$ T_{{\delta^{18} {\text{O}}}} $$ = −3.77 to −5.52(δ18O)]. The application of the local equations to Sr/Ca and δ18O measurements on these corals yielded a range of temperatures of 28.8 ± 1.7°C, comparable to that of the modern Java Sea (28.4 ± 0.7°C). A paleo-salinometer [Δδ18O = ∂δ18O/∂T ( $$ T_{{\delta^{18} {\text{O}}}} $$ − T Sr/Ca)], re-calculated using the local parameters, also suggests Java Sea mid-Holocene paleosalinity similar to modern values.

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.

Significant impacts on cave microclimate from large populations of the bat Rousettus aegyptiacus have been documented in three simple caves in pyroclastic rock of Mount Elgon National Park, Kenya, one of which, Kitum Cave, with few bats, acts as a control, indicating microclimatic variations in the absence of significant biological activity. Seven days of temperature logger records, and on-site mapping of rock and air temperature, humidity, and air flow provide the basis for modeling of heat, water, and CO2 production and dispersion. Internal temperatures in the presence of bats in Mackingeny Cave and Ngwarisha Cave rise to ∼18 °C above ambient (from ∼12 °C to ∼30 °C), but in the control site by only ∼2 °C. Excess bat-generated energy is dissipated by conduction to rock and by ongoing air circulation, the strongest of which accompanies bat entry and exit flights. In Kitum Cave, temperatures that are substantially lower than bat thermo-neutral zone raise concern for Allee effects on long-Term colony fitness: Modeling indicates that a population of at least 100,000 bats should promote colony vitality. Metabolic outputs were modeled to yield corrosional potential: At these population densities, were the caves in limestone, rates of surface denudation caused directly by metabolic outputs would be 1 m in ∼80,000 yr. These results confirm that tropical bats can be effective niche constructionists, by optimizing microclimatic roost conditions, by longer-Term bioerosional optimization of rock surfaces for roosting, and by long-Term niche engineering through zoo-speleogenetic enlargement of roost volume.

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.

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.

The PU-2 stalagmite from Ursilor Cave provides the first dated Romanian isotope record for the Holocene. The overall growth rate of the speleothem was 3.5 cm kyr −1 , corresponding to a temporal resolution of 142 y between each isotope analysis. The 'Hendy' tests indicate that isotopic equilibrium conditions occurred during the formation of PU-2, and hence that it is suitable for palaeoclimatic studies. The relationship between δ 18 O and temperature was found to be positive. This can be interpreted either as rain-out with distance from the west-northwest ocean source of evaporation or shifts in air mass source with changing North Atlantic Oscillation indices. Applying five U-Th thermal ionisation mass spectrometric (TIMS) dates to a 17.5 cm isotope profile (δ 18 O

New dates and analysis of 12 deep and 57 shallow cores allow a more detailed interpretation of the Pleistocene shelf edge of the Florida Platform as found in various facies of the Key Largo Limestone beneath the Florida Keys. In this study a three-phase evolution of the Quaternary units (Q1–Q5) of the Key Largo is presented with new subdivision of the Q5. (1) In the first phase, the Q1 and Q2 (perhaps deposited during oxygen-isotope stage 11) deep-water quartz-rich environment evolved into a shallow carbonate phase, (2) Subsequently, a Q3 (presumably corresponding to oxygen-isotope stage 9) flourishing reef and productive high-platform sediment phase developed. (3) Finally, a Q4 and Q5 (corresponding to oxygen-isotope stages 7 and 5) stabilization phase occurred with reefs and leeward productive lagoons, followed by lower sea levels presenting a sequence of younger (isotope substages 5c, 5a) shelf-margin wedges, sediment veneers and outlier reefs. The Key largo Limestone provides an accessible model of a carbonate shelf edge with fluctuating water depth, bordering a deep seaward basin for a period of at least 300 ka. During this time, at least four onlaps/offlaps, often separated by periods of karst development with associated diagenetic alterations, took place. The story presented by this limestone not only allows a better understanding of the history of south Florida but also aids in the interpretation of similar persistent shelf-edge sites bordering deep basins in other areas.

Speleothems from Oregon Caves National Monument, a dissolutional cave system located in the Klamath Mountains of southwest Oregon, are composed mainly (>90%) of columnar calcite crystals. Columnar calcites form through syndepositional lateral coalescence of crystallites and precipitate under stable hydrodynamic conditions in humid, temperate climates. Numerous discontinuities from short-lived events (

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.

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.

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.

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.

Karren (small-scale dissolutional features) have a great variety of forms and are known by a huge suite of terms. Bare rock forms are sharper and more gravitomorphic than subcutaneous forms, where rock-fracture control may dominate. Four controls operate: (1) physical properties of the solvent (fluid flow, surface tension, and percolation); (2) chemical properties of the solvent (unmodified rainwater, enhanced aggressivity, and reduced aggressivity); (3) chemical properties of the solute (rock solubility); and (4) physical properties of the solute (fractures and rock texture). Large expanses of bare rock karren are called karren fields, the more famous including China's ‘Stone Forest’, Madagascar's ‘Tsingy’, and Mulu's ‘Pinnacles’.

Late Quaternay pipe- or well-like paleokarst features are being exhumed and modified by modern coastal processes along the north-western and northern coasts of Puerto Rico. These features are cigar-shaped tubes dissolved into host rock, with depths up to 4 m, and widths of ≈0.5 m. They can be so densely packed that much of the original deposit has been removed. Most contain evidence of a few millimeters thick calcrete lining, consisiting of micrite laminae, and a zone of indurated rock up to several centimeters thick of micrite and microspar. Many pipes are filled with insoluble material similar in appearance to the insolubles of the host rock but more concentrated, and augmented by material which resemble terra-rossa. At one site the pipes have retained this primary fill material, now somewhat cemented. At the other site the primary fill material, probably sand rather than terra-rossa, was completely removed, the pipes re-filled with marine debris and the whole complex cemented. Some pipes show more than one cycle of filling, emptying and re-filling, and some areas show more than one phase of pipe formation.