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As the northernmost locality yielding one of the most representative Early Pleistocene Gigantopithecus–Sinomastodon faunas in southern China, the Longgupo site has preserved valuable geological archives that have significantly improved our understanding of Pleistocene biostratigraphy and biogeography. A convincing chronological framework of this locality is therefore important to elaborate on the evolution of Quaternary faunas as well as paleoenvironment. To reconcile the existing geochronological results with new advances in geochronology and biochronology, we present here a revised magnetostratigraphic age model based on detailed rock magnetic and paleomagnetic data and strengthened by biochronology as well as recently published electron spin resonance and uranium series (ESR/U‐series) age data. Two geomagnetic polarities were identified from the Longgupo sequence: the upper one is thin and normal, corresponding to the Olduvai normal subchron; and the lower one is distinctly thick and reversed, corresponding to the pre‐Olduvai Matuyama Chron. The age of the Longgupo fauna constrained by this refined magnetochronological framework is therefore estimated to be about 2.5–2.0 Ma, consistent with the newly published ESR/U‐series age of 2.5–2.2 Ma. [ABSTRACT FROM AUTHOR]

Gigantopithecus was a giant ape once lived in Southeast Asia and China during the Pleistocene period. Longgupo and Jianshi Longgudong sites in West-Hubei and Three Gorges region in South China are the northernmost evidences of Gigantopithecus presence in the world up to date. To obtain the detailed chronology of these two sites, paleomagnetic and radiometric dating methods were attempted, including cosmogenic burial dating of the sediment. However, the efforts failed because of the scarce of quartz minerals in the sediment. Combined electron spin resonance and uranium series (ESR/U-series) method which could date the fossil teeth directly with the age range from Early to Late Pleistocene was also applied and the results obtained at Longgupo site already published. Here, we report the first radiometric dating results for teeth carried out from Jianshi Longgudong Western Branch cave which is renowned for the discovery of both Gigantopithecus fossils and undoubted stone artifacts. The main challenge of dating Jianshi Longgudong site is the reconstruction of external dose rate of the fossil samples where their provenance sections were not preserved. The mean radioelement concentrations in the sediments measured in the laboratory with different water content estimation were initially used to calculate the ESR/U-series ages. Our ESR/U-series dating of two mammalian fossil teeth from the lower layer 8 gives a weight mean age of 1512 ± 94 ka, while a mean age of 1044 ± 53 ka was obtained for two teeth from the upper layer 4. These ages support one of the previous paleomagnetic dating interpretation which propose that the hominin fossil layer in Jianshi site was not older than 1.78 Ma, i.e. that the upper boundary of the Olduvai subchron, and are in agreement with the faunal evidence which suggest that Jianshi site is younger than the adjacent Longgupo site dated also by combined ESR/U-series and paleomagnetic methods to 2.0-2.5 Ma. Further study of the site including the radiometric dating study of the fossil layers preserved in the Eastern Branch cave may help to achieve a definitive conclusion of the chronology of Gigantopithecus settlement in Jianshi Longgudong site. [ABSTRACT FROM AUTHOR]

Longgupo cave, located in Chongqing Municipality, China, was discovered in 1984. Sixteen Gigantopithecus teeth and two hominid fossils accompanied with abundant mammalian fossils and stone artifacts were unearthed from the site. Previous dating result is questioned because of the complexity of deposition history. In this study, seventeen mammalian fossil teeth collected from different layers of unit C II and C III (C III′) during the 2003–2006 Sino-Franco joint excavation were analyzed by combined ESR and U-series methods, and calculated with a US-ESR model. In situ dose rates were remeasured in detail in 2012, in order to refine the external dose rate determination. Uranium-series analyses indicate that no obvious uranium leaching has occurred, and all the teeth underwent a very recent uranium uptake history, except one from layer C III 3 of the south wall. The US-ESR results show that the ages of ten teeth from unit C III′ of the north wall are consistent in general, about 2.35 Ma. The ages of seven samples from south wall are not in accordance with the stratigraphic order: three teeth are much younger than the other four, probably attributed to the relative higher uranium concentration and U/Th ratio in the dental tissues and significant higher in situ gamma dose rate. Nevertheless, the three teeth from C III of the south wall give an average age of ∼ 2.48 Ma. The fossil ages obtained in this work combined with paleontological evidence and new paleomagnetic results place Longgupo at the very beginning of the Early Pleistocene. Compared with other early hominid settlements, Longgupo is one of the earliest evidences of hominid settlement in China and East Asia to date. [ABSTRACT FROM AUTHOR]

Yumidong (Corn Cave) is a newly discovered Paleolithic site in the Three Gorges region of central China. Numerous Paleolithic artifacts have been excavated from the sedimentary deposits of the cave in association with faunal remains attributed to the Middle-Late Pleistocene Ailuropoda - Stegodon fauna of southern China. To establish the chronology of the sedimentary sequence (>5 m thick), 14C dating was applied to bone and charcoal samples (n = 6); the U-series method was used to date in situ precipitated speleothems (n = 12), transported speleothem samples (n = 6) and 18 subsamples of a fossil tooth; and the coupled ESR/U-series method was used to date fossil teeth (n = 6). The derived dates were combined using a hierarchical Bayesian approach to generate a unified chronostratigraphy for the Yumidong sequence. In our Bayesian analyses, the 14C and coupled ESR/U-series dates were considered to provide direct age estimates for the target layers, while the U-series dates of the in situ precipitated speleothems and fossil tooth were used as minimum age constraints and those of the transported speleothem fragments as maximum age constraints. The Bayesian analyses provided robust time intervals for the archeological layers: L2-Upper (14–23 ka), L2-Lower (27–63 ka), L3 (106–171 ka), L4 (140–192 ka), L10 (157–229 ka), L11 (181–256 ka), and L12 (214–274 ka) with a probability of 95%, allowing the establishment of a ∼300 ka long geological and archeological history for the Yumidong site and placing it as a reference site for Paleolithic cultural evolution in the Three Gorges region from the late Middle Pleistocene to Late Pleistocene. [ABSTRACT FROM AUTHOR]

The Three Gorges and Western Hubei area in the geographic central part of China was a potential migration corridor for early hominin and mammals linking South and North China during the Pleistocene period. Some key early hominin sites are known in this region where limestone cave and fissure sites are numerous but difficult to date as beyond the dating range of OSL and mass spectrometry U-series method. Here, we report radiometric dating study for such a hominin site, Meipu (Hubei Province), by coupled ESR and U-series dating of nine fossil teeth and cosmogenic 26Al/10Be burial dating of one quartz sediment. The burial age calculated by simple burial model (573 ± 266 ka) gives a minimum age constraint of the sediment. The fossil dating provided two main age groups at 541 ± 48 ka and 849 ± 39 ka, the older age group is in agreement with the U-series age (>630 ka) of the flowstone overlying the fossil layer and the paleomagnetic data which placed the Brunhes-Matuyama boundary in the fossil layer. The reason of this age difference is probably caused by the U-content discrepancy in the enamel of the dated fossil samples. This study exhibits the limitation of ESR/U-series fossil dating and the importance of using multiple dating approach when it is possible in order to identify the problematic ages. • A key hominin site in Three Gorges area at the corridor between South and North China was dated by radiometric methods. • Two radiometric dating methods were applied directly to the fossil layer of the Meipu hominin site. • The results of multiple dating approach were compared to constrain the age of an Early-Middle Pleistocene hominin site. [ABSTRACT FROM AUTHOR]

Several Gigantopithecus faunas associated with taxonomically undetermined hominoid fossils and/or stone artifacts are known from southern China. These faunas are particularly important for the study of the evolution of humans and other mammals in Asia. However, the geochronology of the Gigantopithecus faunas remains uncertain. In order to solve this problem, a program of geochronological studies of Gigantopithecus faunas in Guangxi Province was recently initiated. Chuifeng Cave is the first studied site, which yielded 92 Gigantopithecus blacki teeth associated with numerous other mammalian fossils. We carried out combined ESR/U-series dating of fossil teeth and sediment paleomagnetic studies. Our ESR results suggest that the lower layers at this cave can be dated to 1.92±0.14Ma and the upper layers can be dated to older than 1.38±0.17Ma. Correlation of the recognized magnetozones to the geomagnetic polarity timescale was achieved by combining magnetostratigraphic, biostratigraphic and ESR data. The combined chronologies establish an Olduvai subchron (1.945-1.778Ma) for the lowermost Chuifeng Cave sediments. We also analyzed the enamel d13C values of the Gigantopithecus faunas. Our results show that southern China was dominated by C3 plants during the early Pleistocene and that the Gigantopithecus faunas lived in a woodland-forest ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: Longgupo Cave site, located in Wushan County, Chongqing, China has attracted continuous attention since its discovery of hominid remains in association with late Pliocene-early Pleistocene fauna and numerous lithic artefacts. In 2003–2006, new excavation was carried out on this site, allowing the description of a detailed stratigraphy of the highly complex cave infillings and the sampling of teeth for combined ESR/U-series analyses. Here we report preliminary dating results of seven herbivorous fossil teeth from different archaeological layers of the lowest geological unit (C III). Uranium-series analyses indicate that no obvious uranium leaching has occurred and all the teeth (except one) underwent a very recent uranium uptake history. The obtained US-ESR results show that the age of six teeth are basically consistent, between ∼1.4 and 1.8 Ma. At the same time, we observed an inverse correlation of two samples with the stratigraphical sequence. This could be caused by the distinct uranium uptake history of one sample, high uranium content in the enamel for another or bad estimation of external dose rate. Due to the complexity of the stratigraphic sequence, supplementary in situ gamma dose rate measurement should be performed for all the samples during the following excavations in order to confirm this preliminary ESR/U-series chronology. [Copyright &y& Elsevier]

Abstract: The Dali skull is a key fossil for understanding human evolution in China. It has been attributed either to an archaic Homo sapiens, an evolved Homo erectus or to other species of Homo, such as Homo heidelbergensis. The cranium was discovered in 1978 in Shaanxi Province in a fluvial terrace which was recovered by a loessic sequence including two interglacial palaeosoils. ESR/U-series data analyses were carried out on several teeth recovered from the palaeoanthropological level. Four samples exhibit different kinds of uranium-uptake behaviour, but the results seem to indicate that the cranium is coeval with Marine Isotope Stage (MIS) 8 and that some teeth might be reworked from older deposits. [ABSTRACT FROM AUTHOR]

Abstract: The well-developed, late Cenozoic Nihewan Beds in northern China are amongst the most famous and well-preserved Quaternary strata in East Asia. The Nihewan Basin is also well-known for its mammalian fossils and stone artifacts, which document early human settlements in high northern latitudes (around 40°N). It is a key geological place to study palaeoenvironments and ancient human activities due to the excellent age-control of the formation by palaeomagnetism. In the present paper, the sediments of two Paleolithic sites were dated using the ESR signals of the titanium center in quartz. In order to check the reliability of our analytical procedures, a reference sample collected near the Brunhes/Matuyama (B/M) boundary at the Donggutuo site was firstly analyzed, yielding an age of 750 ± 88 ka. Then, three samples collected from the Dongpo site were analyzed by the same procedures. Our ESR results indicate that the age of the Dongpo cultural layer ranges between 304 ± 12 ka and 333 ± 23 ka, with an average of approximately 321 ± 15 ka. [Copyright &y& Elsevier]

Coupled ESR and U-series analyses of mammalian fossil teeth were carried out on two localities of Yiyuan hominin site (Locality 1 and 3) in northern China. The U-migration history of the fossil samples could be reconstructed by the combination of the two techniques, and overcome the limitation of stand-alone ESR and U-series age estimation. We obtained a combined ESR/U-series age (AU model) range from ∼420 to 320 ka from nine teeth recovered from the two localities, which pinpoints the deposition of hominin layer of Yiyuan site to MIS 11 to 9. The age results in this study places Yiyuan site at the same time range of Zhoukoudian Locality 1 and Hexian Homo erectus sites. Comparing with other hominin sites, this study of Yiyuan Homo erectus site highlights the possibility of coexistence between Homo erectus and archaic H. sapiens in China. [ABSTRACT FROM AUTHOR]

The rarity of Pongo fossils with precise absolute dating from the Middle Pleistocene hampers our understanding of the taxonomy and spatiotemporal distribution of Quaternary orangutans in southern China. Here, we report a newly discovered sample of 113 isolated teeth of fossil Pongo from Zhongshan Cave in the Bubing Basin, Guangxi, southern China. We describe the Pongo specimens from Zhongshan Cave and compare them metrically to other samples of fossil Pongo species (i.e., Pongo weidenreichi , Pongo devosi , Pongo duboisi , Pongo palaeosumatrensis , Pongo javensis , and Pongo sp.) and to extant orangutans (i.e., Pongo pygmaeus and Pongo abelii). The Zhongshan Pongo assemblage is dated using U-series and coupled electron spin resonance/U-series methods. Our results reasonably constrain the Zhongshan Pongo assemblage to 184 ± 16 ka, which is consistent with the biostratigraphic evidence. The Zhongshan Pongo teeth are only 6.5% larger on average than those of extant Pongo. The Zhongshan teeth are smaller overall than those of Pongo from all other cave sites in southern China, and they currently represent the smallest fossil orangutans in southern China. Based on their dental size, and the presence of a well-developed lingual pillar and lingual cingulum on the upper and lower incisors, an intermediate frequency of lingual cingulum remnants on the upper molars, and a higher frequency of moderate to heavy wrinkling on the upper and lower molars, we provisionally assign the Zhongshan fossils to P. devosi. Our results confirm earlier claims that P. weidenreichi is replaced by a smaller species in southern China, P. devosi , by the late Middle Pleistocene. The occurrence of P. devosi in Zhongshan Cave further extends its spatial and temporal distribution. The Pongo specimens from Zhongshan provide important new evidence to demonstrate that the dental morphological features of Pongo in southern China changed substantially during the late Middle Pleistocene. [ABSTRACT FROM AUTHOR]

The Three Gorges Valley, linking the upper and the middle-lower Yangtze River areas is a key area for understanding the geomorphological evolution of the Yangtze River valley, especially the timing of its formation, which remains controversial and occurred following the authors to from the pre-Miocene to Late Pleistocene periods. The 100 m thick Yichang Gravel Layer (YGL), extending over an area >100 km2, is immediately observed downstream of the Three Gorges Valley in the middle Yangtze River Basin also named Jianghan Basin. Studying heavy minerals assemblage and chronology of the YGL deposits can shed lights not only on the geological origin of the sediments and the morphological evolution of the Three Gorges Valley, but also the formation of the Yangtze River Valley. In this study, 18 sediment samples carried out from six representative sections of the unconsolidated YGL and 2 samples from the underlying Neogene and Paleogene bedrocks were analyzed in order to examine their heavy mineral assemblage compositions. These assemblages were compared with modern Yangtze River sediments sampled in Yichang area (n = 5) and present-day sediments from other rivers of the Jianghan Basin (n = 6) to further identify the sediment provenance of the YGL. The statistic results indicate that the heavy minerals identified the YGL dominated by zircon, epidote, titanite, hematite, limonite and ilmenite, are similar to the assemblages observed in the 5 modern Yangtze River sediment samples but differ obviously from both underlying bedrock assemblages, containing kyanite, garnet, rutile and monazite, and other modern river sediments (Jianghan Basin), including hornblende, chlorite, tourmaline, rutile, anatase, spinel and garnet). In addition, 8 sandy samples from the YGL were dated by Electron Spin Resonance (ESR) method using Ti–Li center, showing a deposition age ranging between 1123 ± 139 and 734 ± 183 ka. Based on these observations, we propose that the YGL sediments derived from the upper Yangtze River Basin above the Three Gorges Valley, indicating that the Three Gorges Valley was channelized before 1.12 Ma ago. This result is consistent with previous provenance tracing studies of continuous deposited late Cenozoic sediment from central Jianghan Basin (since 3.0 Ma), which also constrains the incision time of the Three Gorges to ~1.1 Ma. • Yichang Gravel Layer (YGL) represents the first sediment deposition phase after the incision of the Three Gorges valley. • Heavy mineral study shows that YGL materials were mainly sourced from the upper Yangtze River Basin. • ESR chronology indicates that YGL was deposited between 1.12 Ma and 0.73 Ma. • The incision of the Three Gorges valley was therefore realized before. [ABSTRACT FROM AUTHOR]

The Pongo fossil record of China extends from the Early Pleistocene to the Late Pleistocene, but to date, no late Middle Pleistocene samples of Pongo with precise absolute dating have been identified in southern China. Here, we report the recovery of 106 fossil teeth of Pongo from Ganxian Cave in the Bubing Basin, Guangxi, southern China. We dated the speleothems using Uranium-series and dated the two rhinoceros teeth using coupled electron spin resonance/Uranium-series dating methods to between 168.9 ± 2.4 ka and 362 ± 78 ka, respectively. These dates are consistent with the biostratigraphic and magnetostratigraphic age estimates. We further describe the fossil teeth from Ganxian Cave and compare them metrically to samples of fossil Pongo (i.e., Pongo weidenreichi , Pongo duboisi , Pongo palaeosumatrensis , Pongo javensis , and Pongo sp.) from the Early, Middle, and Late Pleistocene and to extant Pongo (i.e., Pongo pygmaeus and Pongo abelii) from Southeast Asia. Based on overall dental size, a high frequency of lingual cingulum remnants on the upper molars, and a low frequency of moderate to heavy wrinkling on the molars, we attribute the Ganxian fossils to P. weidenreichi. Compared with Pongo fossils from other mainland Southeast Asia sites, those from Ganxian confirm that dental size reduction of Pongo occurred principally during the Early and Middle Pleistocene. From the Middle to Late Pleistocene, all teeth except the P3 show little change in occlusal area, indicating that the size of these teeth remained relatively stable over time. The evolutionary trajectory of the Pongo dentition through time may be more complex than previously thought. More orangutan fossils with precise dating constraints are the keys to solving this issue. [ABSTRACT FROM AUTHOR]

Gigantopithecus blacki was once a common primate during Early Pleistocene, distributed throughout southern China, but then it gradually declined with time and finally became extinct probably during Middle Pleistocene. Black Cave in Guangxi (the Zhuang Nationality Autonomous Region) was the first site yielding G. blacki teeth in-situ in 1956. It also produced numerous mammalian fossils belonging to the typical Middle Pleistocene Stegodon–Ailuropoda fauna from sediments overlying the G. blacki level. The present study carried out coupled ESR/U-series dating study of five Bovidae teeth from this palaeontological layer and obtained a weighted mean age of 383 ± 20 ka for this Stegodon–Ailuropoda fauna. This age estimate on fossil teeth is constrained by two 230 Th/U ages of 404 ± 24 ka and 382 ± 9 ka obtained on speleothems formed below and above the level of the Stegodon–Ailuropoda fauna. The Black Cave Stegodon–Ailuropoda fauna can be therefore correlated with MIS 11, and the remains of G. blacki should be older than 400 ka. [ABSTRACT FROM AUTHOR]

Abstract: The use of the ESR titanium (Ti)-center has been proposed to date geological fluvial sediments, because of its quick and complete bleaching by solar light exposure. In this study the Ti-center bleaching behavior of quartz extracted from granite was studied under natural sunlight illumination at different Chinese places of increasing altitudes (Beijing 50m asl, Yinchuan 1100m asl, Germu 2760m asl, Lhasa 3600m asl). Our experiments indicate that the Ti-center signal is totally bleachable by sunlight and that the time necessary to totally bleach the signal ranges from 128h in Beijing (50m asl) to 56h for Lhasa (3600m asl). Another sample from a present-day sandy beach was also studied. This sample does not present a Ti-center signal and it is interpreted as an evidence of the total bleaching of this sample by exposure to subaerial light. These observations confirm that the ESR Ti-center signal can be fully bleached under natural conditions in a sedimentary environment. [Copyright &y& Elsevier]