Showing papers on "Speleothem published in 1999"
TL;DR: In this article, a high resolution study of the oxygen and carbon isotopic composition (1500 measurement pairs) of speleothems from the Soreq cave, Israel, with chronology provided by 53 precise TIMS ages was performed.
648 citations
TL;DR: The speleothem delta function (SDF) as mentioned in this paper provides a new transfer function between the d18O signal of calcite and surface ground temperature, which is based on physical principles, relating the calcite to thermodynamic fractionation, and to the dripwater function, which in turn relates d18 O 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.
Abstract: 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.
196 citations
TL;DR: A long radiometrically dated oxygen isotopic record of continental climatic variations since the penultimate glaciation was obtained from a stalagmite deposited in a sealed cave in Jerusalem as mentioned in this paper.
186 citations
TL;DR: In this article, the growth history of stalagmites under varying climatic conditions has been investigated using a physical and chemical model of calcite precipitation and the supersaturation of the solution from which calcite is precipitated.
Abstract: The morphology and stratigraphy of speleothems are controlled by parameters that depend on climate. These are the water supply rates feeding the speleothem, e.g. a stalagmite, the growth rates dependent on the chemical kinetics of calcite precipitation and the supersaturation of the solution from which calcite is precipitated. To elucidate the basic principles of speleothem growth, a physical…chemical model of calcite precipitation is used to estimate growth rates under various geologically relevant conditions. Furthermore, we present a model that allows the computation of the growth history of stalagmites, i.e. their morphology and stratigraphy under varying climatic conditions. This enables us to see how climatic signals are inscribed into stalagmites. Owing to the counter-balancing effects of some parameters, it is not possible to read climatic conditions backwards from the morphology and stratigraphy of a speleothem in a simple way, but a basic understanding of the growth of speleothems can be a helpful supporting tool in the interpretation of palaeoclimatic records.
176 citations
TL;DR: In this article, two stalagmites from Anjohibe Cave have annual layers made up of inclusion-rich calcite over inclusion-free calcite or of darker aragonite over clear aragonites.
Abstract: 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 Nino) 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 Nino frequency, with Galapagos (Ecuador) coral records of sea-surface temperature in the eastern Pacific, and with accumulation ...
103 citations
TL;DR: The ability to precipitate calcium carbonate in laboratory cultures suggests that these and other bacteria present in the cave may play a role in the formation of moonmilk deposits as discussed by the authors.
Abstract: Microbial communities, where Streptomyces species predominate, were found in association with hydromagnesite, Mg5(CO3)4(OH)2.4H2O, and needle-fiber aragonite deposits in an Altamira cave. The ability to precipitate calcium carbonate in laboratory cultures suggests that these and other bacteria present in the cave may play a role in the formation of moonmilk deposits.
99 citations
TL;DR: A well-preserved, submerged, in situ fossil reef tract lies offshore of the southeast Florida carbonate margin in the Florida Keys and was used to reconstruct reef stratigraphy and paleoenvironments, paleo water depths and paleo sea-levels as mentioned in this paper.
90 citations
TL;DR: In this paper, the age of a speleothem growing over archaeological remains in Nahal Qanah Cave in the east Mediterranean region has been established by using stalagmites.
Abstract: Nahal Qanah Cave, located in the east Mediterranean region, has been inhabited by humans during several periods of the Holocene. These well-dated cultures are used here to establish the age of a speleothem growing over archaeological remains. d18O and d13C from a stalagmite through the last 6000 years display a 1000-2000-year cycle. Depleted d18O and d13C value correlate well with high Dead Sea levels and increased arboreal pollen, suggesting common climatic control affecting the entire region.
70 citations
TL;DR: Carbon and oxygen isotopic trends from seven Midwestern speleothems record significant offsets in the timing of middle-Holocene vegetation change as mentioned in this paper, indicating that the arrival of prairie was offset by 2000 years between caves and pollen sites located only 50 km apart.
Abstract: Carbon and oxygen isotopic trends from seven Midwestern speleothems record significant offsets in the timing of middle-Holocene vegetation change. Interactions of dry Pacific and moist Gulf of Mexico air masses maintained a sharp moisture gradient across Iowa, Minnesota, and Wisconsin such that the arrival of prairie was offset by 2000 years between caves and pollen sites located only 50 km apart. Oxygen isotopes shift concomitantly with carbon in most cases, although these changes are believed to represent increased evaporative enrichment of 18O prior to infiltration during the prairie period.
50 citations
TL;DR: The first groundwater fluorescence intensity increase was demonstrated to lag the autumn increase in groundwater discharge by 10-20 days, suggesting that the first groundwater comprises “old” stored groundwater, whereas later water derives from the overlying soil and has a high organic acid concentration as discussed by the authors.
Abstract: Groundwater discharges onto 16 speleothems and surface climate parameters have been measured in an oolitic limestone site in England. Groundwater recharge is demonstrated to lag behind periods of hydrologically effective precipitation by 30–50 days. With the exception of short periods of high rainfall intensity or quantity, summer rainfall has no effect on groundwater discharge onto the speleothems because of the development of a soil moisture deficit. The first groundwater fluorescence intensity increase was demonstrated to lag the autumn increase in groundwater discharge by 10–20 days, suggesting that the first groundwater comprises “old” stored groundwater, whereas later water derives from the overlying soil and has a high organic acid concentration. Despite the lags, the structure of autumn and winter moisture availability is reflected within the annual fluorescence intensity variations, suggesting that fluorescent organic acids, when trapped within speleothem calcite, may provide a proxy for past winter moisture variations for temperate latitudes.
49 citations
TL;DR: In this paper, the trace element (Mg, Sr and Ba) records from three coeval Holocene speleothems from Great Chamber in GB Cave, southwest England are reported.
Abstract: We report trace element (Mg, Sr and Ba) records based on laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) from three coeval Holocene speleothems from Great Chamber in GB Cave, southwest England. The trace element records are placed on a common timescale on the basis of a suite of TIMS 230Th-234U ages. This permits assessment of the reproducibility of the trace element record in coeval speleothems. The trace element records are not coherent, raising dobuts over the reliability of individual trace element records as potential archives of palaeoenvironmental information. Mg/Sr in speleothem calcite has been proposed as a potential palaeothermometer as Mg partitioning into calcite from water is temperaturedependent, while Sr partitioning into calcite is temperature-independent. However, we present the results of calculations which demonstrate that the observed Mg/Sr values in the three stalagmites cannot have been produced by Holocene temperature changes alone and that other processes m...
TL;DR: One straw stalactite and three stalagmites from the Waitomo district of North Island, New Zealand, were examined for stable isotopes of oxygen and carbon with a view to interpreting their palaeoclimate signal as discussed by the authors.
Abstract: One straw stalactite and three stalagmites from the Waitomo district of North Island, New Zealand, were examined for stable isotopes of oxygen and carbon with a view to interpreting their palaeoclimate signal. Dating was by uranium series and AMS 14C for the stalagmites and by gamma-ray spectrometry for the straw. Records were thus established for about 100 years for the straw and 3.9, 10.1 and 10.2 ka for the stalagmites. The range of variability in d18Oc and d13Cc this century is about two-thirds of that experienced over the entire Holocene, and is most simply explained in terms of the oceanic source area of rain. Stable isotope variations in three stalagmites show some general similarities, but have significant differences in detail, which underlines the necessity to base palaeoclimatic interpretations on more than one speleothem record. The d18Oc of each stalagmite varies positively with temperature, indicating the dominance of the ocean source of evaporation in determining the isotopic composition of...
TL;DR: Speleothem carbon and oxygen isotopic records from Onondaga Cave, south-central Missouri, and Beckham Creek Cave, north-central Arkansas, are compared with the Cupola Pond and Oldfield Swamp pollen series from southeastern Missouri and the Rodgers Shelter and Modoc Shelter vertebrate biostratigraphic sequences from central Missouri and southwestern Illinois.
Journal Article•
TL;DR: Pollen and other microfossils have been recovered from six carbonate speleothems in three Kartchner Caverns rooms: Grand Central Station (samples T2, T3, T4), the Bathtub Room (T11, T12), and Granite Dells (T16) as discussed by the authors.
Abstract: Pollen and other microfossils have been recovered from six carbonate speleothems in three Kartchner Caverns rooms: Grand Central Station (samples T2, T3, T4), the Bathtub Room (T11, T12), and Granite Dells (T16). The carbonate samples were dated from 194-76 Ka. The pollen concentration is greatest (~2 grain/cm3) in sample T11, which has many layers of clastic sediment, and the concentration is least in T4 (~0.05 grain/cm3), which has few mud layers. Therefore, the pollen was probably present in sediments washed into the cave, perhaps during floods. Although the pollen abundance in sample T4 is too low for confident interpretation, modern analogs for the five other samples can be found on the Colorado Plateau in areas that today are wetter and colder than the Kartchner Caverns locality. Agave pollen in samples T2 and T4 indicates that this important source of nectar was in the area during at least the latter part of the Pleistocene. Two orobatid mite exoskeletons recovered in speleothem T4 were probably washed into the cave with the pollen and mud trapped in the speleothems.
Journal Article•
TL;DR: LFG-2, a 39.5 cm tall stalagmite from northwestern Romania, has been dated by U-series α-spectrometric dating, and analyzed for stable isotope variations (δ18O, δ13C) along its growth axis as mentioned in this paper.
Abstract: LFG-2, a 39.5 cm tall stalagmite from northwestern Romania, has been dated by U-series α-spectrometric dating, and analyzed for stable isotope variations (δ18O, δ13C) along its growth axis. The sample grew all the way through oxygen isotope stage 5(a-e), and perhaps for some time into stage 4. In spite of a rather low uranium content and therefore imprecise chronology, the sample provides an interesting stable isotope record with high temporal resolution that correlates favorably with other speleothems and with the deep-sea record. Termination II is well defined in the record as a rapid shift from light (cold) to heavier (warm) δ18O values, when C3 vegetation seemed to dominate. The δ13C in a slow growth zone, corresponding to oxygen isotope stage 5d, as well after the stage 5/4 transition, suggests that C4 plants possibly dominated the surface environment. The δ18O record also correlate quite well with the α-dated FM-2 record from northern Norway.
TL;DR: In this article, a comprehensive study of carbon isotopes in several karst springs and their environs in a contemporary karast environment in the region of the Cracow-Wielun Upland and Western Tatra Mountains, Southern Poland is described.
Abstract: We describe a comprehensive study of carbon isotopes in several karst springs and their environs in a contemporary karst environment in the region of the Cracow-Wielun Upland and Western Tatra Mountains, Southern Poland. We collected samples of water, plants and carbonate deposited on aquatic plants, and obtained (super 13) C values and (super 14) C concentrations. We also investigated a group of the youngest calcium carbonates from caves where deposition is still being observed or ceased no more than a few hundred years ago. The determination of a (super 14) C dilution factor (q) in these carbonates allows us to determine the "true" radiocarbon ages of old speleothems from caves in the area under investigation and enables the use of old speleothems as suitable material for extending the (super 14) C calibration time scale, the "Absolute" age having been determined by U/Th or amino acid racemization (AAR) dating methods. Measurements of delta (super 13) C and (super 14) C concentrations were made on dissolved inorganic carbon (DIC) extracted from water samples. Calculated values of q range from 0.55 to 0.68 and delta (super 13) C values range from -10 per mil to -13 per mil versus VPDB with mean values equal to 0.65 and -12 per mil, respectively. Results indicate that the dissolution process of limestone bedrock is a closed system with the dominating contributor being biogenic carbon dioxide. Isotopic composition of carbon in contemporary plants collected at the karstic springs at 3 localities is highly diverse, with different species distinctly varying in both q and delta (super 13) C values. Extremely light values of (super 13) C (under -40 per mil), observed in Algae and Hyloconium splendens, are correlated with (super 14) C concentrations that are much lower than 100 pMC. Small systematic changes of isotopic composition were found in plants of the same species collected along streams at various distances from the spring. The youngest calcium carbonates from different caves show a relatively high scatter of both delta (super 13) C values and (super 14) C concentration. The lower reservoir effect for (super 14) C is observed in samples with higher value of delta (super 13) C, indicating equilibrium conditions in the sedimentation of carbonate. Pazdur et al. (1995b) presented (super 14) C dating results and paleoclimatic interpretation of 170 (super 14) C analyses of 89 speleothems from 41 caves obtained through 1994. Investigations continued until early 1997, during which time a speleothem, JWi2, was dated by (super 14) C, U/Th and AAR dating methods, and its stable isotope composition (delta (super 13) C and delta (super 18) O) analyzed in detail (reported here). Carbon isotope analyses indicate very large differences among results obtained by U/Th, AAR, and (super 14) C dating methods.
TL;DR: In this article, an alpha-spectrometer analysis of 67 New Zealand speleothem specimens for both 230 Th / 234 U and 231 Pa / 235 U by alpha spectrometry showed that the age concordance between them was excellent.
TL;DR: In the Observatoire cave, a well decorated show cave, it is possible to observe a great number of collapsed sodastraws attributed to the 1887 Ligurian earthquake as discussed by the authors.
TL;DR: In this article, a stalagmite from northwestern Botswana has been analyzed and it was shown that the abundance of detrital materials varies along its growth axis and the positions of those materials preferentially accumulate in the dry season.
Abstract: Analysis of a stalagmite from northwestern Botswana shows that variation in the abundance of detrital grains, which can be conveniently approximated by gray-scale measurements, provides a potentially valuable paleoclimatological record. The stalagmite, which is from near the mouth of Drotsky's Cave, is largely spelean CaCO3. It nonetheless also contains detrital grains of quartz, clays and iron oxides, carbonates, and other minerals. The abundance of those detrital materials varies along the stalagmite's growth axis. Analysis of the positions of those grains indicates that they preferentially accumulate in the dry season. Gray scale (a measure of the lightness or darkness of the cut speleothem) is inversely correlative with detrital content and thus with periods of decreased rainfall. It also correlates positively with historical records of rainfall and with rates of speleothem growth, which are controlled by rainfall. Gray-scale measurements from this speleothem can thus serve as a proxy paleoclimatologi...
15 Aug 1999-Comptes Rendus De L Academie Des Sciences Serie Ii Fascicule A-sciences De La Terre Et Des Planetes
TL;DR: Several caves were visited in different parts of the western USA to observe speleothems that could have been affected by ancient earthquakes as mentioned in this paper, and it seems possible to find evidence of the 1887 Sonora earthquake in Sutherland Peak cave.
Abstract: Several caves were visited in different parts of the western USA to observe speleothems that could have been affected by ancient earthquakes. There are very few caves in California. In Arizona, it seems possible to find evidence of the 1887 Sonora earthquake in Sutherland Peak cave. In New Mexico, the caves of Guadalupe Mountain contain many broken speleothems showing evidence of, at least, one old unknown earthquake.
TL;DR: In this paper, the ages of speleothem samples from two caves near Tangshan Town, Nanjing, determined by thermal ionization mass spectrometry (TIMS), range from older than 500 KaBP to around 20 kaBP.
Abstract: U-series ages of a set of speleothem samples from the two caves near Tangshan Town, Nanjing, determined by thermal ionization mass spectrometry (TIMS), range from older than 500 KaBP to around 20 kaBP. These dated speleothems with unequivocal stratigraphic layers in cave sediments provide basic data to establish a geochronologic sequence for the cave sediments. Together with the buried layers of two hominid craniums, it is argued that the two fossil craniums, probably transported into the cave, deposited in different geological periods. The ages of one flowstone sample and stalagmites mark an upper limit of 500 KaBP for geochronology of No. 1 fossil cranium, and suggest No. 2 fossil cranium deposited within the age range of 500–240 KaBP.
02 Sep 1999-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: A stalagmite sample was taken from a Cold Air Cave (24°S 29°11′E; 1500 m above sea level) in the Makpansgat valley, South Africa, in order to investigate the possibility of using it to reconstruct climatic changes in southern Africa as discussed by the authors.
Abstract: Speleothems have been identified as being useful tools for reconstructing long continuous palaeoclimatic records. A stalagmite sample was taken from a Cold Air Cave (24°S 29°11′E; 1500 m above sea level) in the Makpansgat valley, South Africa, in order to investigate the possibility of using it to reconstruct climatic changes in southern Africa. The sample has been subjected to a series of analytical techniques that include radiometric ( 230 Th/ 234 U) dating, stable isotope analysis ( δ 18 O, δ 13 C) and grey scale intensity analysis. In addition it was decided to perform Particle Induced X-ray Emissions (PIXE) analysis using a proton micro-probe. The advantage of this technique was that time variations in elemental concentrations could be obtained for each stratified layer (on an average 2.2 mm or ∼10 yr) in the stalagmite and variations in elemental deposition within these layers. Analysis for each discernible layer of the speleothem, from the present to 3000 yr BP, was undertaken and is presented in this paper.
TL;DR: In this article, a stalagmite sample from Sutherland, Scotland, has been found to have a period of enhanced growth that lasted for four years and has been dated to 1135 ± 130 BC (Baker et al., 1995).
Abstract: Studies of a stalagmite sample from Sutherland, Scotland, have identified a period of enhanced growth that lasted for four years and has been dated to 1135 ± 130 BC (Baker et al., 1995). This episode is unique within this sample and has not been observed elsewhere. The authors correlate it with the Icelandic volcanic eruption at 1021 + 130/-100 Bc that produced the Hekla-3 (H-3) tephra. There is, however, no direct evidence for a causal relationship between volcanic activity in general, or the H-3 eruption in particular, and the growth patterns of the stalagmite. As an alternative to the volcanic explanation of enhanced growth, we suggest that the speleothem could reflect environmental changes associated with woodland decline and the spread of blanket peat.
01 Jan 1999
TL;DR: The U-series ages of a set of speleothem samples from the two caves near Tangshan Town, Nanjing, determined by thermal ionization mass spectrometry (TIMS) range from older than 500 KaBP to around 20 kaBP as mentioned in this paper.
Abstract: U-series ages of a set of speleothem samples from the two caves near Tangshan Town, Nanjing, determined by thermal ionization mass spectrometry (TIMS), range from older than 500 KaBP to around 20 kaBP. These dated speleothems with unequivocal stratigraphic layers in cave sediments provide basic data to establish a geochronologic sequence for the cave
01 Jan 1999
TL;DR: In this article, two stalagmites and five pool-spar crystals from Closani cave (Southern Carpathians, Romania) were dated by U-series method and 17 dates obtained show that the speleothem growth was slightly inhibited, yet not halted during the cold Oxygen Isotope stage 4.
Abstract: Clo?ani during Oxygen Isotope stages 5-3 and its paleoclimatic Clo?ani during Oxygen Isotope stages 5-3 and its paleoclimatic Clo?ani during Oxygen Isotope stages 5-3 and its paleoclimatic Clo?ani during Oxygen Isotope stages 5-3 and its paleoclimatic significance significance significance significance ABSTRACT Two stalagmites and five pool-spar crystals from Closani cave (Southern Carpathians, Romania) were dated by U-series method. The 17 dates obtained show that the speleothem growth was slightly inhibited, yet not halted during the cold Oxygen Isotope stage 4. Although both stalagmites were located within a zone of currently stable meroclimate, their growth rates were very different. Sample C6 showed a remarkable constant and low growth rate between the Eemian and the last glacial maximum, while sample C8 grew fast, mostly within OI substage 3.3. This contrast enables us to assume that the eastern end of the Crystals Passage was still linked to the entrance area some 40 ka ago. On the other hand, since the slow-growth of C6 is indicative for a stable meroclimate, its initiation postdates the total clogging of the link between the paleo-ponor of Cioaca cu Brebenei and Crystals Passage. This gives a minimum estimate of the underground stream deepening/capture time.