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Calcite surface has been reported by cavers and scientists over the last decades. Here, we present a methodological work aimed at quantifying that growth. We suggest a method of draping old photographs of a part of the Gournier Cave onto a 3D model. This work relies on a collection of photographs taken by cavers. We have chosen to study a site for which the maximum number of photographs was available. The series of photographs over time makes it possible to overcome the limitation of calcite crust dating. The acquisition of the 3D model has been achieved using terrestrial LIDAR. Then, photographs were draped over this 3D model to digitize the calcite/limestone limit. The four pictures that were used span the 1950 to 2014 growth period. We demonstrate that the growth began before 1964 and that it is not directly related to an airflow increase in the cave due to the opening of a sump by cavers in 1992. The surface increase is ascribed to regional changes, but we cannot ascertain whether climatic or environmental controls are its main drivers. Furthermore, it remains uncertain whether an acceleration of calcite growth was driven by local changes induced by an increase in airflow.

Here we present the first record of Marine Isotope Stage (MIS) 7 from Sardinia, based on a U-Th-dated speleothem from Crovassa Azzurra cave, which also grew during MIS 5. Carbonate precipitation was continuous during MIS 7, while two multi-millennial hiatuses interrupted growth during MIS 5. These hiatuses occurred during times of unstable climate, but local karst-specific conditions are considered to have played an important role as well. δ13C values mostly reflect soil bioproductivity and vegetation density. During less humid periods these values reflect bedrock δ13C values, because of a semi-closed system and/or sulphuric acid-driven bedrock dissolution. δ18O changes were governed by the interplay of rainfall amount and moisture source. Disentangling these two effects was possible by comparing δ13C and δ18O values, whereby both isotopes co-vary during periods when δ18O was dominated by the amount effect. Changes in the relative proportion of Atlantic and Mediterranean moisture sources was the main control on δ18O at times when δ18O was decoupled from δ13C. δ18O variations during MIS 5 are synchronous with Greenland stadials (GS) and interstadials (GI) GS 26, GI 25, GI-GS 22, GI-GS 21. With the exception of GS 22, these climate oscillations did not affect soil bioproductivity, and δ18O mirrors the relative proportion of Atlantic and Mediterranean moisture sources. GS 22 was a prominent arid period in Sardinia, in accordance with other regional palaeoclimate archives. High soil bioproductivity is indicated by δ13C values for MIS 7e and MIS 7c-a; the latter interval was characterized by a 30 kyr-long time span of warm and humid conditions in Sardinia. Soil bioproductivity decreased markedly during MIS 7d and the climate became drier. The latter period, also constrained by δ18O data, lasted significantly shorter in Sardinia than in central Europe. As indicated by changes in δ13C and δ18O relationships, variations in moisture source are also recorded for MIS 7, with Mediterranean-dominated rainfall during MIS 7e and 7c followed by a shift toward Atlantic-dominated rainfall. • A Mediterranean palaeoclimate archive recording MIS 7 and MIS 5. • The first MIS 7 palaeoclimate record from Sardinia. • Hints of moisture source variability during pre-Holocene interglacials. [ABSTRACT FROM AUTHOR]

This short article provides detailed descriptions of custom-made and commercially available hand-held drilling gear and options for water-flushing units specifically designed to obtained good-quality core material from speleothems even in remote cave regions. We use small-diameter (6-7 mm) diamond drill-core bits to obtain aliquots of calcite (as little as a few hundred milligrams) from the interior of the basal part of in-situ stalagmites. These small cores are used to date the onset of stalagmite growth and occasionally to obtain other compositional information. Larger diameter drill-core bits produce cores 25-32 mm in diameter and up to 1.3 m in length which reveal internal structures and provide axial transects for chemical and isotope analysis and material for preparation of thin sections. This system has been successfully employed to sample flowstone and thick stalagmites. Given the growing interest in speleothem as archives of past environmental change, careful sample selection is primordial to keep the impact of sampling in these unique environments at a minimum. Low-invasive drilling is an essential technique and maximizes the amount of information gained.

An 8-m-high wall in a quarry on the west end of Cayman Brac exposes the upper part of the Cayman Formation (Miocene), the lower part of the overlying Pedro Castle Formation (Pliocene), and the Cayman Unconformity, which is a karstic unconformity that separates these formations. The modern-day karst surface caps the Pedro Castle Formation. This exposure also includes cross-sections through two filled caves—the “Lower Cave” (> 8 m long, up to 2.5 m high) and “Upper Cave” (> 23 m long, up to 2 m high)—that are housed in the Cayman Formation and Pedro Castle Formation, respectively. The Lower Cave is filled with caymanite, which is formed of laminated, varicolored dolomitized mudstones, and grainstones that contain scattered marine fossils (e.g., foraminifera, red algae). This cave, connected to the Cayman Unconformity by a small-diameter tunnel, evolved as part of the karst system that developed during the Messinian lowstand (7.3–5.3 Ma). The cave was filled and dolomitized prior to deposition of the Pedro Castle Formation. The Upper Cave is filled with a wide spectrum of lithotypes, including dolostones, calcareous mudstones, terra rossa, gastropod coquina, coated grains, and speleothems. U/Th dating indicates that some of the flowstones are > 500,000 years old whereas others are only ~ 21,000 years old. Dolostones and mudstones in the basal part of the Upper Cave contain marine fossils (foraminifera, red algae) whereas the younger deposits are devoid of such fossils. The Upper Cave and its deposits developed after the sediments of the Pedro Castle Formation had been deposited and lithified. Development of the cave filling deposits, which includes a clear transition from marine to non-marine influences, was controlled by eustatic sea-level changes and/or westward tectonic tilting of Cayman Brac that occurred after the Pedro Castle Formation became exposed, probably during the Late Pliocene. [ABSTRACT FROM AUTHOR]

Panxian Dadong Cave located in the western Guizhou is a very important Paleolithic site in China. At this site bone and stone artifacts, human teeth and mammalian fossils (known as Ailuropoda-Stegodon fauna) were found, and the site was previously dated to 120–300 ka using ESR/uranium-series methods. In this study, we successfully extracted fine quartz grains from flowstone and silty carbonate-rich sediments in the excavated area. The quartz extracts displayed excellent luminescence properties, and satisfied the SAR (single-aliquot regenerative dose method) acceptance criteria. The sensitivity-corrected OSL signals are not saturated at a dose up to about 1400 Gy. The cultural unit was OSL dated to 190–300 ka, corresponding to MISs 7–8. The flowstone deposits overlying the cultural unit were determined to be 13–190 ka and the silty carbonate-rich sediments underlying the cultural unit to be 300–360 ka. The optical ages are in general agreement with the coupled ESR/U-series and U-series ages. [ABSTRACT FROM AUTHOR]

ABSTRACT Speleothems are usually composed of thin layers of calcite (or aragonite). However, cemented detrital materials interlayered between laminae of speleothemic carbonate have been also observed in many caves. Flowstones comprising discontinuous carbonate layers form due to flowing water films, while flood events introduce fluviokarstic sediments in caves that, on occasion, are recorded as clayey layers inside flowstones and stalagmites. This record provides a potential means of understanding the frequency of palaeofloods using cave records. In this work, we investigate the origin of this type of detrital deposit in El Soplao Cave (Northern Spain). The age of the lowest aragonite layer of a flowstone reveals that the earliest flood period occurred before 500 ka, though most of the flowstone formed between 422 +69/-43 ka and 400 +66/-42 ka. This suggests that the cave was periodically affected by palaeoflood events that introduced detrital sediments from the surface as a result of occasional extreme rainfall events, especially at around 400 ka. The mineralogical data enable an evolutionary model for this flowstone to be generated based on the alternation of flood events with laminar flows and carbonate layers precipitation that can be extrapolated to other caves in which detrital sediments inside speleothems have been found. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Proxy records from high-altitude locations predating the Last Glacial Maximum are rare but could provide invaluable insights into the response of alpine catchments to the rapid climate fluctuations which characterized the last glacial period. Here we present a detrital-rich flowstone record from Entrische Kirche Cave, an inneralpine cave situated close to the accumulation area of the Pleistocene ice-stream network of the European Alps that expanded repeatedly into the lowlands during glacial maxima. U–Th dating of this calcite is challenging due to high detrital Th. However, petrographic and stable isotope analyses in conjunction with associated clastic cave sediments provide useful insights into the climatic boundary conditions during speleothem formation and into the paleoenvironmental processes which operated in the ~2000m-high catchment above the cave. Our data show that millennial-scale temperature fluctuations had a first-order control on the periglacial activity and vegetation in the catchment which strongly influenced the formation and infiltration of detritus into the karst aquifer. The brown laminated and brown dendritic fabrics that compose much of the detrital-rich flowstone succession reflect these environmental processes. The temperature-dependence of periglacial and permafrost processes allows to constrain the amount of cooling relative to the present-day mean annual air temperature that is required to initiate detrital-rich calcite formation in Entrische Kirche Cave, i.e. −2.5°C (minimum) to −6°C (maximum), respectively. White inclusion-poor calcite that is intercalated with the detrital-rich calcite indicates warm (interstadial) conditions and geomorphological stability in the catchment area. One such phase has been U–Th dated to 88.3±6.9ka (i.e. Greenland Interstadial 21 or 22). [Copyright &y& Elsevier]

Detailed field examination, U-Th age dating, and stable isotope analysis of Vetemica flowstone and shelfstone deposits have been employed in order to unravel details about the geological history of Veternica Cave (Medvednica Mountain, Croatia). The study was carried out in the hydrologically inactive part of the main cave channel, which is developed mainly along the unconformity between Triassic dolostone and Miocene limestone. For 180 m from the cave entrance, (located at 320 metres above sea level (asl)), the morphology of the main channel reflects exclusively phreatic conditions in the cave until the end of its hydrological activity. From 180 to 390 m, the phreatic channel has a secondary vadose entrenchment in the bottom part as marked by massive flowstones at elevations from 306 to 313.5 m asl. From 390 m farther inside the cave (in the upstream direction), the main channel has a tall, narrow cross-section and is of mainly vadose origin. In this part of the cave shelfstone precipitates are observed at 9 different levels ranging from 318.8 to 320.2 m asl, indicating the water palaeolevels in the cave. U-Th dating revealed the age of the highest shelfstone (320.2 m asl) of ~380 kyrs BP, and the age of the lowermost analyzed shelfstone (318.9 m asl) of ~245 kyrs BP Dating of flowstone deposits, located below the shelfstone level, revealed their formation from ~235 to 205 kyrs BP. A relatively rapid water table lowering and transition from phreatic to vadose conditions occurred within the cave, from ~245 to 235 ka BE between formation of the youngest shelfstone (representing phreatic conditions below their level) and the oldest flowstone (marking the beginning of vadose conditions). The results provide unique new information about Vetemica Cave genesis and geomorphologic evolution of the Medvednica Mountain area. [ABSTRACT FROM AUTHOR]

Abstract: New evidence from uplifted marine isotope stage (MIS) 5e carbonate deposits in the Gulf of Corinth demonstrate two rapid, sub-orbitally forced, sea-level oscillations in the early part of MIS 5e. Microbial bioherms with inter-grown marine coralline algae are interpreted as early highstand deposits. Presence of thin vadose flowstone (speleothem) coating inter-bioherm surfaces mark a short-lived regression of >10 m, followed by sea-level recovery and re-establishment of the highstand, marked by coralline algae coating inter-bioherm cavity surfaces. These marine algae are then coated by a younger vadose flowstone, thick enough to provide an uncontaminated U/Th date of 134.8±2.0 ka. The dated flowstone is itself encrusted by marine fauna and the entire sequence overlain by highstand marine sediments and marine aragonite cements dated to 114–118 ka, part of the sustained MIS 5e highstand. The age of the younger flowstone demonstrates that the early highstand occurred before 134.8±2.0 ka, and uplift arguments suggest that the bioherms are unlikely to be older than ∼136 ka. These data are consistent with the notion that most of termination II (TII) sea-level rise had occurred before 135 ka; indeed they suggest sea-level at this time reached about 2–4 (±4) m below present sea-level, 6–18 (±4) m higher than previous estimates. This early highstand was itself punctuated by a rapid sea-level oscillation of >10 m (as yet undated), and this oscillation, supported by new TII sea-level data from the Red Sea [Siddall, M., Bard, E., Rohling, E.J., Hemleben, C., 2006, Sea-level reversal during termination II, Geology, 34, 817–820.], probably occurred in about 1000 yr. The flowstone dated at 134.8±2.0 ka is interpreted to record the early part of the ‘Aladdin''s Cave'' regressive event from Papua New Guinea, although in Greece only the first 16 m of the event is recorded. The new data presented here support a recently published Red Sea TII sea-level curve: they also highlight minor discrepancies in the absolute dating of these early MIS 5e sea-level events worldwide. [Copyright &y& Elsevier]

Abstract: Reconstructions of African palaeoenvironments are essential for a full understanding of early hominin evolution, but they are often hampered by low-resolution or discontinuous climatic data. Here we present high-resolution oxygen (δ 18O) and carbon (δ 13C) isotope time series for the Pliocene/early Pleistocene (1.99 to 1.52 Ma) of South Africa, derived from the Buffalo Cave flowstone deposit. The δ 18O data are dominated by variations at the orbital precession period (18–23 ka), as is typical for records of sub-tropical monsoon rainfall. The δ 13C data indicate the proportion of savannah grasses (C4 plants) compared to trees and shrubs (C3 plants), and this signal is dominated by an obliquity periodicity (40 ka), commonly associated with high-latitude ice-sheet dynamics. A rapid increase in savannah grass proportions between 1.78 and 1.69 Ma coincides with a pulse in African mammal turnover, and lends support to an adaptive link between the appearance of African Homo erectus and the increasingly savannah-dominated environment. [Copyright &y& Elsevier]

Caves in South Africa preserve a rich record of early hominin and early modern human development and have been the subject of much research. U Pb dating of speleothems, particularly flowstones, has provided a much-needed chronology for cave sites in the Cradle of Humankind, the coastal cliff caves at Pinnacle Point and at the archaeological site of Wonderwerk Cave. The U Pb ages range from ~3 Ma to just under 1 Ma and altogether represent a relatively large dataset of 35 U-Pb ages, from 34 flowstone samples, consisting of a total of 291 individual matched U and Pb isotope analyses. We look for patterns within these data and find that in general, the U concentration has little to no effect on age quality, while the lower Pb concentration, the better. Our data confirms the expected negative exponential relationship between U Pb age and 234U/238U. There is no apparent relationship between U concentration and residual 234U/238U, suggesting U concentration patterns are controlled by 238U, not 234U. We divide the 35 U-Pb ages into three categories defined by the % error on the U Pb age (the good, the bad and the ugly). We use the U and Pb isotope data, thin section petrography and laser ablation trace element transects through the flowstones to investigate the factors controlling the quality of the ages. The 'good' ages are produced by the coincidence of several features: a large number of points (10 or more) defining their isochrons, radiogenic 206Pb/204Pb ratios, with a few very radiogenic points defining the line of the isochron, U concentrations of ~1 ppm and well-preserved trace element signals. 'Bad' ages are caused by deficit in one of these factors but may be redeemed with additional analysis to better define the line of isochron and constrain initial 234U/238U. The 'ugly' ages are attributable to low levels of radiogenic Pb, a low spread of isochron and high Pb concentrations, possibly from detrital material. We show what a completely recrystallized flowstone looks like, where the original trace element signals are completely obliterated, and it is impossible to resolve a U Pb age. The thin section petrography reveals all flowstones have undergone heavy diagenesis, with the dominant fabric observed consisting of mosaic calcite with relic aragonite. However, we argue that the preservation of trace element signals, in particular the abrupt, sympathetic step-like variation is Sr, U and in some cases Ba and Mg, indicate that this diagenesis is conservative. We identify a mixture of crystal and fluid dominated trace element patterns, both of which are ultimately related to flow dynamics, in turn related to changes in external hydroclimate. This hints at the potential to extract valuable palaeoclimate records out of these old, U Pb dated flowstones, which would be very interesting given their association with important early human evolution sites in South Africa. [ABSTRACT FROM AUTHOR]

<b>Background and Objective:</b> Ureolytic bacteria are bacteria capable of hydrolyzing urea. In construction, these bacteria are known to help improve soil stability. One of the habitats of ureolytic bacteria is cave ornaments such as gourdam, flowstone, stalagmite and stalactite. This study aims to find isolates and characterization of ureolytic bacteria in cave ornaments. <b>Materials and Methods:</b> Urea-CaCl<sub>2</sub> was used as the isolation medium and urea agar medium was used as a qualitative urease test for cave ornament bacteria isolate. This study applied a survey method and tested for gram staining, spore staining, mannitol test, catalase test and lactose test for characterization. <b>Results:</b> There were 17 isolates positive for urease from 30 isolates from the isolates of cave ornament bacteria. The characteristics of 17 ureolytic bacteria isolates were 2 isolates gram-negative basil with negative lactose test and 1 isolate positive glucose and 1 isolate negative glucose. Total 15 isolates gram-positive basil with spore staining results, 14 isolates spore-positive with 2 isolates positive mannitol and 12 isolates negative mannitol and 1 isolate spore-negative with negative catalase. <b>Conclusion:</b> Total 17 ureolytic bacteria isolates were found from cave ornaments. Biochemical characterization showed 1 isolate of <i>Proteus</i> spp., 1 isolate of <i>Pseudomonas</i> spp, 2 isolates suspected of being <i>Bacillus megaterium</i> or <i>Bacillus subtilis</i>, 12 isolates of <i>Bacillus cereus</i> and 1 isolate of <i>Lactobacillus</i> spp.