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1.
Abstract

The northern Pacific Coast is an important area for understanding human colonization of the Americas, but Late Pleistocene coastal sites are rare and interglacial sea level rise has inundated the continental shelf and the primary areas where Paleocoastal archaeological sites are likely to occur. Here we outline a terrestrial archaeological survey project designed to identify Paleocoastal sites on Santa Rosa Island, California. Using reconstructions of ancient shorelines and paleogeography, we predicted that sites might be found where lithic resources, freshwater springs, caves or rockshelters, and strategic vistas drew Paleocoastal peoples into the island interior. We identified nine new Paleocoastal sites, including four radiocarbon dated to >11,000 cal b.p. that are among the oldest sites on North America’s Pacific coast. Our targeted survey demonstrates an important technique for investigating island and coastal settings where sea level rise remains a significant challenge for locating early sites.  相似文献   

2.
In 2004 numerous hominid footprints, along with diverse animal footprints, were found in the Late Quaternary strata of Jeju Island, South Korea. However, the age of the sediments in which the footprints were found is still controversial. Previous age estimates included radiocarbon ages of ca. 15,000 yr BP (Late Pleistocene) and quartz optically stimulated luminescence ages of ca. 7000 yr BP (mid-Holocene). In this study we report on 11 AMS 14C dating results from a new set of samples collected from the footprint-bearing strata and from associated sediments. Despite some variations and age reversal, all samples collected from the footprint-bearing strata yielded 14C ages of late Pleistocene. These ages are comparable with previous radiocarbon dating results. Furthermore, the presence of the proboscidean footprints attributable to woolly mammoths in the footprint-bearing strata supports the radiocarbon dating results. Based on the new radiocarbon dates and the presence of the alleged mammoth footprints, the age of the hominid footprints found at Jeju Island is thought to be late Pleistocene (about 19,000–25,000 cal yr BP). Therefore, this is the second discovery of hominid footprints dated to the Pleistocene age in Asia, and the first to be discovered in Korea.  相似文献   

3.
Abstract

The Epipaleolithic site of Tor al-Tareeq (WHS 1065) was discovered in 1982 by Burton MacDonald's Wadi Hasa Survey in west-central Jordan, surface collected and tested in 1984, and partially excavated in 1992. The earliest and best represented occupation is an early Epipaleolithic industry, overlain in places by an ephemeral geometric industry identified by a higher incidence of geometric microliths. Six radiocarbon determinations span the period between 16,900 and 15,600 b.p. and confirm an early Epipaleolithic date but the subsequent geometric phase has not been dated. The site consists of a series of camps, near a collapsed rockshelter and a spring, and strung out along the shore of a mildly-alkaline, late Pleistocene lake. The permanent water and varied resource zones surely made the locale attractive in an otherwise arid landscape. Faunal remains and pollen from the site indicate diverse resources in conditions substantially different from those of today. This report examines a wide range of archaeological and paleoenvironmental data in order to understand aspects of the regional system of settlement and subsistence of which Tor al-Tareeq was a part. Continuing research in the eastern Hasa drainage seems likely to provoke a reassessment of current models of hunter-gatherer adaptation during the Epipaleolithic in the southern Levant.  相似文献   

4.
The Middle to Upper Paleolithic transition (MP-UP transition) is considered a major technological and cultural threshold, at the time when modern humans spread “out of Africa”, expanded from the Levant into Europe and possibly into central and northern Asia. The dating of this techno-cultural transition has proved to be extremely difficult because it occurred sometime before 40,000 radiocarbon years before present (14C years BP), which is close to the end of the effective dating range of radiocarbon. Other dating methods such as Thermoluminescence (TL) or Electron Spin Resonance (ESR) are not sufficiently precise to date the recorded archaeological MP-UP transition in the Levant. Here we report a consistent set of stratified radiocarbon ages on freshly excavated charcoal from Kebara Cave, Mt. Carmel (Israel), that span the late Middle Paleolithic (MP) and Early Upper Paleolithic (EUP) This study applied novel strategies to improve sample preparation techniques and data analysis to obtain high-resolution radiocarbon models. From this study it is proposed that the MP-UP transition for this site can be placed immediately after 45,200 ± 700 14C years BP and before 43,600 ± 600 14C years BP or from 49/48 to 47/46 radiocarbon calibrated years before present (years Cal BP).  相似文献   

5.
The debate about the complex issues of human development during the Middle to Upper Palaeolithic transition period (45–35 ka BP) has been hampered by concerns about the reliability of the radiocarbon dating method. Large 14C anomalies were postulated and radiocarbon dating was considered flawed. We show here that these issues are no longer relevant, because the large anomalies are artefacts beyond plausible physical limits for their magnitude. Previous inconsistencies between 14C radiocarbon datasets have been resolved, and a new radiocarbon calibration curve, IntCal09 (Reimer et al., 2009), was created. Improved procedures for bone collagen extraction and charcoal pre-treatment generally result in older ages, consistent with independently dated time markers.  相似文献   

6.
ABSTRACT

Since a radiocarbon chronology of the Dalton culture in the Southeast was first proposed, several new sites have been dated. I propose a new chronology based on radiocarbon dates from sites in the Dalton Heartland and its eastern periphery using Bayesian statistical models in OxCal and an analysis of the associated diagnostic projectile points. The analyses indicate that the Dalton culture probably evolved from the Clovis or Gainey phenomena about 12,680?cal?BP (ca. 10,700?BP) and lasted at least until ca. 10,400?cal?BP (ca. 9,200?BP), if not several centuries later. I propose early and late Dalton phases that follow changes in how Dalton points were made and resharpened. It appears that the people living to the east of the Heartland followed a different trajectory of projectile point evolution. There, notched points appear about 11,500?cal?BP, while in the Heartland, true notched points do not appear in large numbers until the Graham Cave point over 2,000 years later. The chronologies demonstrate that early, coeval, region-wide cultural changes may not have been the norm. They also raise interesting questions about how people in the Heartland and its eastern periphery interacted.  相似文献   

7.
The geomorphological evolution of the upper Chienti river basin, during the late Pleistocene and the Holocene, was characterized mainly by numerous landslides, strongly affecting the river dynamics, that produced falls, deviations and in some cases total obstructions with the formation of lakes sometimes extending for some kilometres. Moreover, particularly during the Holocene, phytoclastic and phytohermal travertine deposits were deposited in correspondence of steps along the river bed; one of these deposits, by means of radiocarbon dating, has been dated between 8260 ± 100 yr BP and 7740 ± 80 yr BP. Stromatolithic travertine is also present at the base of Holocene channels, slightly incised on the top of the upper Pleistocene alluvial plain.  相似文献   

8.
Fragments of charcoal are present in floodplain alluvium of the San and Strwi?? rivers in the Polish part of the Bieszczady Mountains, Polish East Carpathians. They occur as single clasts or in lenses in the basal part of fine-grained alluvium, together with unburnt wood debris, or in the middle part of the vertical sequence of the floodplain alluvium. 14 samples of charcoal from the upper courses of the San (ca. 50 km) and the Strwi?? (ca. 10 km) were dated with radiocarbon. The obtained dates fall mainly in the 15th through 19th century interval; only one sample is markedly older (9th–10th century). Taxonomic composition of the charcoal source wood was also studied and compared with that of coeval forests. Correlation of the charcoal age with the history of economic development of the studied region indicates that charcoal is of anthropogenic origin: older charcoal from intense slash-and-burn deforestation, while younger charcoal was produced by local industries.  相似文献   

9.
In the present series we have dated two samples from a previously unknown pilework E. of the Kastelholm castle, two other logs from old layers to the S. of the castle, two charcoal samples from a layer E. of the castle, four samples of various materials from a ditch SE of the castle, and one sample from outside the NE part of the castle. All the samples were carefully pre‐treated, δ13C normalization performed and the measurements extended to reach a statistical uncertainty of usually less than ±60 years. The results are given in radiocarbon years and calibrated.  相似文献   

10.
Border Cave is well-known for its Middle Stone Age (MSA) sequence and associated hominids, as well as for the earliest demonstrable Later Stone Age (LSA) (c. 38,000 b.p.) strata in southern Africa. Detailed lithostratigraphic and sedimentological study permits identification of 8 Pleistocene sedimentary cycles, including 6 major cold phases and 2 intervening weathering horizons. The 2 youngest cold phases are associated with the LSA and have 8 14C dates 38,600-13,300 b.p. By gauging sedimentation rates in finer and coarser sediments, duration of sedimentary breaks, and allowing for differential compaction, the excellent radiocarbon framework provided by 28 available 14C dates can be extrapolated to the 6 cold intervals and 2 palaeosols that are older than 50,000 b.p. These clearly span oxygenisotope stages 4, 5 and 6, placing the base of the MSA deposits at c. 195,000 b.p., Homo sapiens sapiens at c. 90,000–115,000 b.p. and the sophisticated, microlithic “Howieson's Poort” industry at 95,000 b.p. These results require radical reassessment of the age and nature of the MSA complex and of the earliest evolution of anatomically-modern people.  相似文献   

11.
Abstract

KS043 is a stratified site associated with a complex of artesian springs. The archaeological remains, as well as a series of radiocarbon determinations, date the site to between 4800 and 4200 b.c. Our study suggests a connection between Saharan pastoralists, forced to move into oasis areas by increasing aridification, and the first Predynastic cultures of the Nile Valley. The site is the only well dated stratified settlement attributed to the Late Neolithic in the eastern Sahara that is characterized by Tasian cultural traditions.  相似文献   

12.
ABSTRACT

Submerged shell midden sites and natural shell deposits can have similar characteristics and can be difficult to distinguish archaeologically. We excavated two test units from a large (at least 35 m×70 m) submerged shell mound in Fort Neck Cove in southern Rhode Island to assess whether it was natural or cultural in origin. This mound had been recognized as a potential archaeological feature as early as the 1970s. Excavation, radiocarbon dating, and subsequent laboratory analysis of excavated materials suggest that the mound was a natural oyster reef rather than a submerged archaeological site. No artifacts were found; there was no clear evidence for human modification of any shells; small species that would not have been targeted as food were present; and δ13C values of oyster shells from the mound were consistent with freshwater input into their growth environment, suggesting that they grew in an estuarine environment that did not exist prior to the inundation of the ponds. The stratigraphically oldest radiocarbon date we could obtain (430–190 cal BP, 2σ range), from 70 cm below the pond floor, placed deposition of shells at least 3,000 years after the inundation of the pond. The excavation methods that we used and the process of testing, irrespective of whether the feature is cultural, are valuable contributions to the methodological literature on submerged site archaeology and help provide insight for other researchers working to discern natural from cultural shell midden sites.  相似文献   

13.
The National Museum of Denmark and the Department of Geography at the University of Copenhagen have collaborated on a project investigating burial mounds near early Medieval churches. The aim was to identify a possible continuity in cult sites across the shift to Christianity in the late Viking Age. Charcoal samples from 18 mounds were radiocarbon dated but the results showed they were far older than expected. Control dating undertaken on burial mounds of known age confirmed that charcoal in the mound fill can at least be up to 3000 years older than the mound itself. As charcoal can survive in the surface soil layer for millennia, in spite of ploughing, bioturbation and frost, it may also dominate the charcoal pool of the grass or heather turfs used in the mound construction. Therefore, the article concludes, charcoal cannot be used to securely date archaeological features built with turfs and it is important to be aware of the possible presence of very old charcoal when selecting material for dating archaeological features, even those which otherwise would be judged unaffected by material from earlier archaeological periods.  相似文献   

14.
Abstract

The use of radiocarbon dating to analyze mortar and charcoal inclusions within mortar or plaster is a useful way to date the construction of architecture, particularly when options for other chronometric methods are limited. In the Yalahau region of northern Quintana Roo, Mexico, members of the Yalahau Regional Human Ecology Project have faced challenges in dating buildings made of large blocks of stone in the Megalithic architectural style. The Megalithic style poses serious problems for any analysis, as excavating into structures with stones weighing several tons can be dangerous, expensive, and time consuming. Additionally, there are no associated sculptures, texts with dates, or other traditionally accessible chronological markers. These factors have resulted in a reliance on a ceramic chronology despite the uncertainty of the dating of many ceramic types in this region, as well as the questionable contextual associations between recovered ceramics and architectural construction phases. Megalithic-style structures at the ancient Maya site of El Naranjal have residual mortar with charcoal inclusions left behind during the mortar-making processes that can be extracted and dated with AMS 14C methods. Several samples of mortar and charcoal were obtained from structures 1 and 10 from exposed exterior walls and an interior vault. The resulting dates confirm the date for the construction based on ceramics excavated from the same site.  相似文献   

15.
From the late Pleistocene to early Holocene in Japan, subtropical and temperate forest elements moved northwards. This affected human choices and access to food sources. More settled patterns of living spread northwards gradually, and northern hunting-gathering-fishing people began cultivating vegetables and cereal crops. This poster reports the presence of ancient starch residues on stone artefacts in Kagoshima Prefecture, southern Kyushu. The oldest residues recovered are dated by context to about 30,000 14C yr BP. If such residues can be identified, it may be possible to detect a hypothesized early phase of tropical plant movement northwards during warmer climate peaks in the late terminal Pleistocene, as well as during the long period of Holocene warming that followed. As an initial step towards identification, the morphological characteristics and condition of the starch granules are described and compared to those of other sites in early Japan.  相似文献   

16.
Abstract

Archaeologists have contributed much new information relating to types of domestic dogs that were present in pre-Columbian North America. Questions yet to be answered are: Where did the basal stock for these early Western Hemisphere dogs originate? What were they like morphologically? Some reported early canids, particularly those from late Pleistocene deposits, are subject to question as to their domestic role. These and related problems are discussed.  相似文献   

17.
Antlers and bones of reindeer (Rangifer tarandus L.) are the most frequently found vertebrate remains from the Late Glacial deposits of Southern Scandinavia. The Danish collection now consists of more than 350 specimens and of these 47 have been radiocarbon dated extending the range of occurrence in the area with ca. 1300 14C yr. Thus the first occurrence is pushed back to ca. 12?500 14C yr BP (late Bølling chronozone) while the youngest date lies at ca. 9200 14C yr BP (late Preboreal chronozone) establishing that the reindeer survives well into the Holocene. The seasonal dates of the reindeer indicate for the first human occupation (the Havelte group from the Bølling period) a summer, autumn and early winter occupation, with reindeer, as well as man, apparently being absent during the coldest winter months. Finally, it is shown that Southern Scandinavia acted as a calving area throughout the Late Glacial and Early Holocene thus discrediting the North–South model of reindeer groups moving from a wintering area in Southern Scandinavia to a calving area in the foothills of the North European plain.  相似文献   

18.
Uncertainties regarding the magnitude of freshwater radiocarbon reservoir effects can introduce random errors into dates on archaeological freshwater carbonates. As a result, many archaeologists avoid dating freshwater shells unless no other datable materials are available. The chronology of prehistoric occupation of the former Naval Petroleum Reserve No. 1 (NPR-1) at Elk Hills, Kern County, has been established with 50 radiocarbon dates on freshwater mussels (Gonidea and Anodonta sp.). Characterization of any freshwater radiocarbon reservoir effect is crucial for the accurate interpretation of inferred settlement and subsistence changes on the Elk Hills. Paired charcoal and freshwater mussels sampled from closely associated contexts were dated to identify a freshwater reservoir effect. Paired Anodonta and Gonidea sp. shells were dated to investigate interspecific differences in fractionation. Results indicate that a 340 ± 20 14C yr correction should be applied to conventional 14C dates on freshwater carbonates in the Buena Vista Basin before calendar calibration. Evidence of interspecific differences is inconclusive. Dates recalibrated with the reservoir correction indicate that widespread occupation of the Elk Hills is correlated with increasing precipitation towards the end of the Medieval Climatic Anomaly and during the Little Ice Age, suggesting that slough resource exploitation may have been driven by regional population pressure rather than drought-related declines in aquatic productivity.  相似文献   

19.
Archaeologists have long recognized the problem of the “old wood” effect in radiocarbon dating charcoal and wood samples, the age of which may be hundreds of years older than their use by humans. Such problems have resulted in significant changes in how most researchers select wood and charcoal samples for 14C dating, with many now using relatively short-lived carbonized materials for dating. Despite the significant strides made in our understanding of the potential biases of the “old wood” effect, little emphasis has been placed on the possible impacts of dating “old shell” in archaeological deposits. The use of marine shell for 14C dating is widespread in coastal areas around the world, including a growing emphasis on the dating of individual shell artifacts via Accelerator Mass Spectrometry (AMS). In dating shell artifacts, we have obtained several dates older than associated 14C dates for short-lived subsistence remains from the same deposits, including great disparities (>10,000 years) and more subtle differences (≥100 years). These discrepancies appear to be due to the use of old shells by humans to make beads and other artifacts, including shells collected from fossil deposits, older archaeological sites, and beaches. The problems caused by the use of old shells to make beads and other artifacts are surmountable through careful sample selection, analysis of multiple 14C dates on a variety of materials, and proper calibration procedures.  相似文献   

20.
The skeleton of a human adult female was excavated from alluvial sediments along the Gulf Coastal Plain of Texas. She was buried face down in an extended position with her hands crossed beneath the waist. Initial radiocarbon ages indicated that this skeleton dated to the late Pleistocene. Geoarchaeological and archaeological excavations at the site, coupled with new radiocarbon ages, amino acid compositional data, and an analysis of the previously reported radiocarbon ages obtained from the skeleton instead suggest a middle Holocene age for this burial.  相似文献   

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