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1.
Electron spin resonance (ESR) and mass spectrometric U-series dating has been carried out on teeth recovered from K?lna cave during the excavations of 1961–76. Linear and early uptake (LU and EU) age estimates are similar due to low internal U content of the teeth. In general, ESR ages decrease upward in the section, but teeth from stone-rich (“lumpy”) layers give anomalously young ages, due to uneven dose-rate distribution. Elephant molars also give anomalously low ages, apparently due to self-absorption of gamma dose. Disregarding anomalous data, earliest appearance of Micoquian lithics and last occurrence ofDicerorhinus kirchbergensisin layer 9b is dated to 69±8 ka, which places them near the oxygen isotope stage (OIS) 5a/4 boundary. Neanderthal remains and the latest occurrence of Micoquian lithics in level 7a are dated to 50±5 ka, in good agreement with an uncalibrated radiocarbon date for this level of about 45 ka. The interstadial character of the fauna of this level also agrees with its date which places it in OIS 3. We also report that three stadial/interstadial cycles recognized in the lithological, faunal and palynological record of levels 9b through 7a at Kölna occurred during the timespan from about 70 to 50 ka.  相似文献   

2.
In 1985 a Neanderthal skeleton was found in the cave of Kebara in southern Mt. Carmel. Electron spin resonance (ESR) dates have been obtained on tooth enamel of gazelles found in layer X, just overlying the layer in which the skeleton was found. Assuming early uptake of uranium by the teeth, they yield an age of 60 ± 6 ka; assuming gradual, linear uptake of uranium yields an age of 64 ± 6 ka. Both age estimates are consistent with a previous estimate for the skeleton, based on TL dating of burnt flint, of 60 ± 4 ka.  相似文献   

3.
We have obtained ESR ages on 18 teeth from archaeological levels AH16-AH27 exposed at the east profile in compartment E at Karaïn Cave. This sequence exhibits a transition in lithic assemblage from a Classic Charentian to a Karaïn (Zagros-type) Mousterian between levels AH27 and AH25, and two calcite-cemented soils at levels AH22 and AH16 which have been interpreted as climatic warm phases. Since we found no systematic increase in tooth ages with depth, we assigned this sequence a mean early uptake (EU) age of 108 ± 23 ka and mean linear uptake (LU) age of 121 ± 27 ka, on the basis of 37 subsamples from 16 teeth. In this site, the precision of individual tooth ages suffered little from the problems associated with uranium uptake. However, this advantage was offset due to uncertainties arising from the rather inhomogeneous nature of the enclosing strata which contained various sizes of limestone blocks with intervening sediment. This led to difficulties in ascribing a precise annual gamma radiation dose to individual teeth in such a "lumpy" gamma radiation field. Considerable scattering of the individual tooth ages occurred mainly because the annual gamma dose comprised greater than 50% of the total annual dose to the individual teeth. On the basis of the ESR dating results, we infer that deposition of the two different lithic assemblages and both the penultimate and the final climatic warm phases at Karaïn probably occurred during oxygen isotope stage 5. We also conclude that these lithic assemblages are significantly different than contemporaneous Levantine Mousterian industries which occur about 700 km to the southeast.  相似文献   

4.
SHEN GUANJUN 《Archaeometry》1986,28(2):179-184
The travertine layers of the Prince Cave have been dated by the U-series methods. The age of the lower part of the breccia Br2, where a human iliac fossil bone was discovered, is between 110 and 160 ka. and the upper part of Br2, together with the breccia Br1, between 79 and 160 ka. The reliability of the results is confirmed not only by the consistency of the dates obtained from samples in close proximity, but also by the agreement between two independent dating methods: Th-230/U-234 and Th-227/Th-230.  相似文献   

5.
The history of the interlaboratory comparison of TL dating results in Poland started in the 1980s. At that time the Lublin, Warsaw and Silesian laboratories made the first attempts at TL dating of the same loess samples from the Odonów profile. However, the cooperation ceased for many years due to great differences in the obtained TL age estimates. The next interlaboratory comparisons were made in the years 2000–2009 for the loess samples from several Polish (Dybawka, Tarnawce, Dankowice, Biały Kościół) and Ukrainian (Boyanychi, Halych, Velykyj Hlybochok, Yezupil) profiles. Most of the compared dates, obtained for the loess deposits from the Upper Pleistocene and younger part of the Middle Pleistocene, were consistent. This encouraged us to undertake the Gdańsk-Lublin interlaboratory cooperation in dating of 200-700 ka old loess deposits. Nine samples were taken from the Ukrainian profile Mamalyha 2 in 2009 for this purpose. The TL dating results indicate that comparable dates are obtained in two laboratories for loess deposits younger than 300 ka BP. The TL signal obtained in the Gdańsk laboratory for the samples older than 300 ka BP was saturated so such samples should not be dated by the multi-aliquot regeneration method. The results obtained in the Lublin laboratory for these deposits (489–682 ka) confirm that it is possible to date loess deposits older than 500 ka. It probably results from the use of total-bleach method with preheating at 160°C for the equivalent dose determination.  相似文献   

6.
This paper reports a series of radiocarbon dates on bone samples coming from the Mousterian of Acheulian Tradition (MTA) Layer 3 at the top of the Pech de l'Azé IV (Pech IV, France) Middle Palaeolithic sequence. All of these samples showed evidence of human impact, and they were prepared using current pre-treatment techniques to remove or identify contamination. The results indicate that the MTA at Pech IV started prior to the current limit of radiocarbon calibration (circa 50 ka BP) and ended by 45 ka cal. BP. These dates are supported by additional TL and ESR dates from the sequence, confirm previously suggested correlations between Pech I and IV, and generally fit within the known age range for the MTA. The oldest dates reported here may also lend support to still older TL dates for the MTA that taken together suggest that the MTA extended from late MIS 4 or early OIS 3 through to the end of the Middle Palaeolithic in southwest France.  相似文献   

7.
Because only a few radiometric data are actually available, the chronology of the Amudian – a blade-dominated industry of the Acheulo-Yabrudian Cultural Complex (AYCC) of the late Lower Paleolithic in the Levant – is still not well constrained. Qesem Cave offers the opportunity to enhance our knowledge of the chronological position of this industry which is unique to the Levant. The Qesem Amudian bearing layers yielded also human remains showing affinities with those of modern populations recovered in the Middle Paleolithic sites of Skhul and Qafzeh. The results presented here are the first attempt to apply the TL and ESR/U-series dating methods at this site and these methods yielded results which are generally in agreement. They support a time interval of hominid-bearing occupation of the areas of the cave where Amudian lithic artifacts were recovered during MIS 8 and likely 9 for the Deep Pit Area, and during MIS 8 and possibly 7 for the Upper part of the sequence (Square K/10 and the Eastern Microfauna-Bearing Area). An older occupation of the cave is also conceivable on the base of two dating results (MIS 11).  相似文献   

8.
The Laibin hominid represents one of the rare finds of modern Homo sapiens in China, rare for its relative completeness and well-established stratigaphic provenance. This paper presents the results of mass spectrometric U-series dating of intercalated calcite samples from the Laibin site. The capping flowstone and the calcite vein, which sandwich the hominid fossil-containing deposits, date to 38.5 ± 1.0 and 44.0 ± 0.8 ka, setting respectively the minimum and maximum ages to the fossils. The second flowstone layer is 112.0 ± 1.4 ka old, indicating that the cultural sequence may possibly extend to somewhere between 44 and 112 ka. Securely dated Laibin finds should be of importance in reconstructing human physical and cultural evolution in the region.  相似文献   

9.
The age of Neanderthal remains and associated sediments from El Sidrón cave has been obtained through different dating methods (14CAMS, U/TH, OSL, ESR and AAR) and samples (charcoal debris, bone, tooth dentine, stalagmitic flowstone, carbonate‐rich sediments, sedimentary quartz grains, tooth enamel and land snail shells). Detrital Th contamination rendered Th/U dating analyses of flowstone unreliable. Recent 14C contamination produced spurious age‐values from charcoal samples as well as from inadequately pretreated tooth samples. Most consistent 14C dates are grouped into two series: one between 35 and 40 ka and the other between 48 and 49 ka. Most ESR and AAR samples yielded concordant ages, ranging between 39 and 45 ka; OSL dating results permitted adequate bracketing of the sedimentary layer that contained the human remains. Our results emphasize the value of multi‐dating approaches for the establishment of reliable chronologies of human remains.  相似文献   

10.
This paper presents a series of new single-grain optically stimulated luminescence (OSL) ages for the Still Bay at Blombos Cave, South Africa, and compares them to previously published OSL, thermoluminescence (TL) and electron-spin resonance (ESR) ages for this site. Details are provided about the measurement and analytical procedures, including a discussion of the characteristics of the OSL signals of individual quartz grains. This forms the basis for further investigations into the sensitivity of the equivalent dose (De) estimates to a range of different analytical approaches, including changes in the size of the test dose, the choice of signal integration interval, the subtraction of an appropriate background, and isolation of the most light-sensitive (‘fast’) component of quartz OSL. We also report the results of an inter-operator test of De determination using seven new samples from Blombos Cave, and demonstrate the reproducibility of results obtained for two samples that had been dated previously at another laboratory and were measured and analysed again in this study. Together, these tests validate the robustness of the Blombos Cave single-grain OSL age estimates to a variety of alternative OSL dating procedures. We have incorporated, for the first time, these ages for Blombos Cave into a data set of all single-grain OSL ages for Still Bay and Howieson's Poort sites across southern Africa, and have used a statistical model to re-evaluate the timing and duration of the Still Bay industry. We calculate the most plausible start and end dates of the Still Bay as 72.2 ka and 71.3 ka, respectively – amounting to a duration of 0.9 ka – and estimate (with conventional 95% confidence) that this industry began no earlier than 75.5 ka, ended no later than 67.8 ka and lasted no longer than 6.6 ka.  相似文献   

11.
On the west side of the Winnemucca Lake subbasin, Nevada, distinctive deeply carved meter-scale petroglyphs are closely spaced, forming panels on boulder-sized surfaces of a partially collapsed tufa mound. The large, complex motifs at this side are formed by deeply carved lines and cupules. A carbonate crust deposited between 10 200 and 9800 calibrated years B.P. (ka) coats petroglyphs at the base of the mound between elevations of 1202 and 1206 m. Petroglyphs above the carbonate crust are carved into a branching form of carbonate that dates to 14.8 ka. Radiocarbon dates on a multiple-layered algal tufa on the east side of the basin, which formed at an elevation of 1205 m, as well as a sediment-core-based total inorganic carbon record for the period 17.0–9.5 ka indicate that water level in the Winnemucca Lake subbasin was constrained by spill over the Emerson Pass Sill (1207 m) for most of the time between 12.9 ± 0.3 and ≥9.2 ka. These and other data indicate that the lake in the Winnemucca Lake subbasin fell beneath its spill point between 14.8 and 13.2 ka and also between 11.3 and 10.5 ka (or between 11.5 and 11.1 ka), exposing the base of the collapsed tufa mound to petroglyph carving. The tufa-based 14C record supports decreased lake levels between 14.8–13.2 ka and 11.3–10.5 ka. Native American artifacts found in the Lahontan Basin date to the latter time interval. This does not rule out the possibility that petroglyph carving occurred between 14.8 and 13.2 ka when Pyramid Lake was relatively shallow and Winnemucca Lake had desiccated.  相似文献   

12.
We report the results of a test excavation of deposits in a limestone cave sub-chamber located beneath the main chamber of Liang Bua, Flores, Indonesia; the discovery site of the small hominin species, Homo floresiensis. Well-preserved remains of extinct Pleistocene fauna and stone artefacts have previously been identified on the surface of a sediment cone within the sub-chamber. Our excavation of the deposits, at the base of the sediment cone in the sub-chamber (to 130 cm depth) yielded only a few fragmentary bones of extant fauna. Uranium/Thorium (U-series or U/Th) dating of soda straw stalactites excavated from 20 to 130 cm in depth demonstrates that the excavated sediments were deposited during the Holocene. Red Thermoluminescence (TL) dating of the sediments at the base of the excavation (130 cm depth) indicates these sediments were last exposed to sunlight at 84 ± 15 ka (thousand years), similar to red TL ages of cave sediments from the main chamber. Together, these results indicate that the surface faunal remains, which are morphologically analogous to Pleistocene finds from the main chamber excavations, were transported to the sub-chamber relatively recently from the main chamber of Liang Bua and probably originated from conglomerate deposits at the rear of the cave and from deposits around the front entrance. There is no evidence for hominin occupation of the sub-chamber, instead it seems to have acted as a sink for cultural materials and fossil remains transported from the surface via sinkholes. Despite the small number of finds from the test excavation, it is possible that more extensive excavations may yield additional transported cultural and faunal evidence at greater depths.  相似文献   

13.
The Pu'u Wa'awa'a trachytic glass deposit located on the Big Island of Hawai'i was a source of lithic tools for much of Hawaiian prehistory. Routinely encountered at habitation sites, the glass has the potential to provide absolute dates based upon the degree of surface hydration. Infrared photoacoustic spectroscopy and secondary ion mass spectrometry were used to monitor the diffusion of water in archaeological and experimental samples. Accelerated laboratory hydration experiments show that water diffusion in trachytic glass containing a structural water content of 0.16% ± 0.03% is linear with time. Application of the calibration to trachytic glass artifacts from the Kahalu'u habitation cave have produced chronometric dates in the 17th–18th centuries. These age estimates are in agreement with radiocarbon dates and artifactual data that bracket the site occupation. However, the glass dates do not correlate well with site stratigraphy and this suggests that slight sample imperfections that retain water may be one factor that results in ages that are too early for later occupation levels.  相似文献   

14.
This paper presents the first chronometric dates for sediments that contain a Mousterian industry in Dalmatia (south Croatia). Electron spin resonance (ESR) dating was conducted on two teeth from the Mousterian level E1 at the site of Mujina Pećina. Additionally five bone and one charcoal sample from five different strata of origin at this site were dated by accelerator mass spectrometry (AMS). Assuming 30% moisture for both the gamma and beta dose rate calculations, the mean LU ESR age estimate is 44±5 ka for level E1, which is statistically indistinguishable from the mean EU ESR age estimate of 40±7 ka. A single, uncalibrated 14C age from the E1/E2 interface yielded an age estimate of 45,170 +2780/−2060 years bp while the mean of the five samples from overlying Mousterian levels is 39±3 ka. The true (calibrated) age of this mean is about 42 ka, which means that the entire stratigraphic profile in Mujina Pećina apparently was very rapidly deposited, and that the ESR age, regardless of uptake model is in good agreement with the calibrated 14C mean age. Temporally, Mujina Pećina overlaps with Pontinian Mousterian sites in west-central Italy and Vindija level G3 from northwestern Croatia. However, there are notable differences between the Mousterian industry from Mujina Pećina and these other sites. Collectively, the Croatian sites yield important evidence on the adaptation of European Mousterian people.  相似文献   

15.
Fifty years ago, an ethnographic expedition found primitive human fossils at Lake Eyasi, Tanzania. Subsequent emphasis has centered almost exclusively on cranial morphology, neglecting the discovery site and associated finds. Fauna has been deemed “essentially modern” and racemization dates suggest a late Pleistocene age for the hominid remains; these assessments have been advanced as consistent with a “terminal Middle Stone Age” antiquity. Based on recent observations at the site and new sediment analyses, a provisional sequence is now proposed: an earlier formation, the Eyasi Beds, is distinguished from later Pleistocene deposits, the Mumba Beds, the latter being partially calibrated by uranium series and radiocarbon dates. This evidence indicates that the Eyasi Beds, the probable source of the human fossils, are older than 130,000 years, and the fauna may include seven extinct large mammal species. Documented Eyasi Beds artifacts are mostly unspecialized Middle Stone Age types; no typological or technical features suggest later MSA specializations or innovations foreshadowing Later Stone Age industries. A series of core tools from the lakeshore suggests an industry of Sangoan aspect. All lines of evidence from the locality contradict the young amino acid racemization dates; artifacts and fauna, including archaic Homo sapiens remains, are of probable Middle Pleistocene age.  相似文献   

16.
The infrared radiofluorescence (IR-RF) dating technique was applied to eight fluvial samples that were collected from two sediment cores at the Heidelberg Basin located near Viernheim and Ludwigshafen in southwest Germany. Based on the IR-RF derived ages of the samples it was possible to establish a chronological framework for the Mid-Pleistocene fluvial deposits of the Heidelberg Basin. The results allow us to distinguish between four main periods of aggradation. The lowermost sample taken from 100 m core depth lead to an IR-RF age of 643 ± 28 ka pointing to a Cromerian period of aggradation (OIS 17–16). For the Elsterian it is now possible to distinguish between two aggradation periods, one occurring during the Lower Elsterian period (OIS 15) and a second during the Upper Elsterian period (OIS 12–11). For the so called Upper interlayer (or “Oberer Zwischenhorizont” — a layer of organic-rich and finer-grained deposits), the IR-RF results point to a deposition age of around 300 ka, with samples taken directly on top and out of this layer yielding IR-RF ages of 288 ± 19 ka and 302 ± 19 ka, respectively. Hence, the measured IR-RF ages clearly point to a deposition during the Lower Saalian period (OIS 9–8) whereas earlier studies assumed a Cromerian age for the sediments of the Upper Interlayer based on pollen records and also mollusc fauna. The new IR-RF dataset indicates that significant hiatuses are present within the fluvial sediment successions. In particular the Eemian and Upper Saalian deposits are missing in this part of the northern Upper Rhine Graben, as the 300 ka deposits are directly overlain by Weichselian fluvial sediments. It is obvious that time periods of increased fluvial aggradation were interrupted by time periods of almost no aggradation or erosion which should have been mainly triggered by phases of increased and decreased subsidence of the Heidelberg Basin.  相似文献   

17.
This paper presents ESR (electron spin resonance) ages of rhinoceros and equine tooth enamel from the open‐air Palaeolithic site of Bollschweil on the western edge of the Black Forest near Freiburg, Germany. Bollschweil is one of very few archaeological sites in southern Germany to yield Lower or Middle Palaeolithic faunal and lithic materials from a buried, open‐air context. The geological context of the archaeological remains indicates that the loessic sediments have been reworked. Excavation at this site yielded a cold‐period fauna characterized by bones of mammoth, horse, large bovids and wooly rhinoceros. In the absence of any clear chronostratigraphic marker horizons, the age of the finds could not be determined without the use of a chronometric dating method. Lithic artefacts from the site, including a handaxe and a side scraper, suggest either a Middle Pleistocene or early Late Pleistocene age. The ESR dating results indicate that the deposit enclosing the archaeological finds should be assigned to oxygen isotope stage (OIS) 6, although there exists some possibility that some teeth were deposited later, in OIS 5.  相似文献   

18.
The Longwangchan Paleolithic site, situated on the Yellow River terraces in the Hukou area, Shaanxi province, China, was found in 2003–2004, and two areas (Localities 1 and 2) of the site were excavated in 2005–2008. Abundant stone artifacts including microliths, a grinding stone fragment and a shovel, with some animal bones and shells, were recovered from Locality 1. In this study, the cultural deposits from Locality 1 were dated using radiocarbon and optical dating techniques, and the sediment properties of the deposits were analyzed. The results show that the age of the deposits ranges from 29 to 21 ka and most of them were deposited between 25 ka and 29 ka. This indicates that corresponds to late Marine Isotope Stage (MIS) 3 and early MIS 2. During the human occupation period, the climate in this area became colder and drier. Sediments from beds where the grinding slab and the shovel were found were dated to ∼25 ka, which is the oldest among the grinding stones found in China. The microliths and the grinding stone are important evidence for an incipient socio-economic process that eventually led to the regional transition from hunting-foraging to farming.  相似文献   

19.
Palaeomagnetic measurements on sediments from Petralona cave. Greece indicate a stable, single component remanence of normal polarity. Redeposition experiments established the ability of the sediments to acquire the direction of the geomagnetic field. Magnetic properties and Mössbauer spectra of sediments and magnetic concentrates show that magnetite, which is slightly non-stoichiometric, and haematite are present in the sediments from the cave. The magnetite dominates the magnetic properties and exhibits pseudosingle domain behaviour. Using rstimated deposition rates for the sediments in the cave. and the fact that U Th and ESR dates which can be stratigraphically correlated to the palaeomagnetic section range from 200 to 750 ka. implies that the section represents a time span of about 150 180 ka within the Brunhes epoch. From this. the age of a human cranium found in the cave 25 years ago is estimated to be not older than 620 ka.  相似文献   

20.
The fluvio-lacustrine sequences in the Nihewan Basin, northern China, provide important terrestrial archives about Palaeolithic settlements and, therefore, about early human occupation in high northern latitude in East Asia. Here we present detailed ESR dating of the Donggutuo Palaeolithic site, located in this basin. Four levels A, B, C and E of the Donggutuo archaeological layer yield ESR ages ranging from 1060±129 ka to 1171±132 ka with a mean of 1119±132 ka. The ages are consistent with the paleomagnetic data, which show that the Donggutuo Palaeolithic site lies just below the onset of the Jaramillo normal subchron (0.99–1.07 Ma). Furthermore, our results indicate that the reliable ESR dating range of bleached quartz using Ti-Li centre can be effectively extended to 1100 ka and the Ti-Li centre was zeroed before the last deposition, which requires improvement of the understanding of the bleaching mechanism conditions.  相似文献   

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