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1.
Cactus Hill is located in the Virginia Coastal Plain on a terrace above the Nottoway River. The site has a record of occupation that spans the Holocene and also offers evidence of humans late in the Pleistocene before Clovis time. Soil investigations identified several deposit types, and demonstrated that multisequal eolian sands forming the site's primary core are arrayed in spatially and temporally discrete horizons. Resting atop an ancient paleosol, the earliest sand stratum (19,540 ± 70 14C yr B.P.) is marked by a conspicuous but culturally sterile buried surface horizon. Eolian sand above this surface supports another sequum in which Clovis and underlying “Blade” artifacts are associated with a fainter surface horizon and pronounced subsoil lamellae. Early Archaic and successively younger artifacts occur above the Clovis level in a more weakly developed uppermost sequum. This soil and cultural stratigraphy, together with considerations of regional topography, demonstrate that the landscape has evolved incrementally since about the last glacial maximum. © 2004 Wiley Periodicals, Inc.  相似文献   

2.
Franchthi Cave, bordering Kiladha Bay, in Greece, is a key archaeological site, due to its long occupation time, from?~?40,000 to?~?5000 year BP. To date, no clear evidence of Neolithic human dwellings in the cave was found, supporting the assumption that Neolithic people may have built a village where there is now Kiladha Bay. During the Neolithic period/Early Holocene, wide areas of the bay were indeed emerged above sea level. Bathymetric and seismic data identified a terrace incised by a valley in?~?1 to 2 m sediment depth. Eight sediment cores, up to 6.3-m-long, were retrieved and analysed using petrophysical, sedimentological, geochemical, and chronostratigraphic methods. The longest core extends into the exposure surface, consisting of a layer of carbonate rubble in a finer matrix, representing weathering processes. Dated organic remains place this unit at?~?8500 cal year BP. It is overlain by stiff silty mud representing an estuarine environment. This mud is capped by reduced sediments with roots marking an exposure surface. A shell-layer, dated to?~?6300 cal year BP, overlies this terrestrial sequence, reflecting the marine transgression. This layer occurs at 10.8 mbsl, 7.7 m deeper than the global sea level at that time, suggesting tectonic subsidence in the area. It is overlain by finer-grained marine carbonate-rich sediments. The top of the core shows traces of eutrophication, pebbles and marine shells, all likely a result of modern anthropogenic processes. These results are interpreted in the context of human occupation: the exposed surface contains pottery sherds, one dating to the Early to Middle Neolithic period, indicating that Neolithic people were present in this dynamic landscape interacting with a migrating coastline. Even if the artefacts are isolated, future investigations of the submerged landscape off Franchthi Cave might lead to the discovery of a Neolithic village, which eventually became buried under marine sediments.  相似文献   

3.
The Mockingbird Gap site is one of the largest Clovis sites in the western United States, yet it remains poorly known after it was tested in 1966–1968. Surface collecting and mapping of the site revealed a dense accumulation of Clovis lithic debris stretching along Chupadera Draw, which drains into the Jornada del Muerto basin. We conducted archaeological testing and geoarchaeological coring to assess the stratigraphic integrity of the site and gain clues to the paleoenvironmental conditions during the Clovis occupation. The 1966–1968 excavations were in stratified Holocene eolian sand and thus that assemblage was from a disturbed content. An intact Clovis occupation was found elsewhere in the site, embedded in the upper few centimeters of a well‐developed buried Bt horizon formed in eolian sand, representing the regional Clovis landscape. Coring in Chupadera Draw revealed ∼11 m of fill spanning the past ∼11,000 14C years. The stratified deposits provide evidence of flowing and standing water on the floor of the draw during Clovis times, a likely inducement to settlement. © 2009 Wiley Periodicals, Inc.  相似文献   

4.
Multidisciplinary Quaternary investigations in the Minusinsk Basin in the upper Yenisei River region and other southern Siberian continental depressions have produced evidence of prehistoric peopling pre‐dating the last glacial stage (>100 ka BP). Abundant ‘pebble tools’ and bone artefacts exposed from eroded alluvia of the Yenisei River terraces indicate repeated occupation of this territory since the Middle Pleistocene. A new stage of expansion of the early human occupation habitat occurred around the last interglacial (OIS 5e) by a Middle Palaeolithic (Neanderthaloid?) population characterized by a core and flake stone industry and open‐air occupation sites. The key camp/kill‐processing site at Ust‘‐Izhul’, dated to c. 125 ka BP and documenting complex behavioural activities, is so far the most complete in situ pre‐Late Palaeolithic site found in Siberia. This unique record provides new insights into the timing and the palaeoenvironmental conditions of the Pleistocene colonization of north‐central Asia.  相似文献   

5.
《Quaternary Science Reviews》2007,26(22-24):2724-2737
This paper reviews the Pleistocene evolution and human occupation of the River Trent, the major fluvial artery draining Midland Britain, and places it within a modern Quaternary context. In contrast to the sedimentary records of the River Thames and the erstwhile Bytham system, which extend back to the early Pleistocene, present knowledge of the terrace sequence of the Trent, its tributary systems and associated ancestral courses extends back only to the Anglian glaciation (Marine Isotope Stage (MIS) 12), although the regional pre-Anglian drainage configuration is demonstrably complex. The post-Anglian sequence is well developed, with major terrace sand and gravel aggradations associated with each subsequent cold stage. Temperate-climate sediments correlating with MIS 7 and 5e have been recorded, although deposits relating to earlier interglacials during MIS 11 and 9 have yet to be identified. Evidence for human occupation in the form of Lower and Middle Palaeolithic artefacts has been recorded from terrace sediments correlated with MIS 8 and MIS 4, but the majority of this material is heavily rolled and abraded, suggesting significant reworking from older deposits. This review demonstrates that there is a rich palaeo-environmental record from the Trent but the lack of a high-resolution chronostratgraphic framework raises issues about correlation with other systems.  相似文献   

6.
The Balkan Peninsula represents one of the most important human pathways into and out of Europe during the Pleistocene. Mishin Kamik cave, located in the karst region of Western Stara Planina, has a rich faunal content and shows promising features indicating a human occupation site with the discovery of potential bone artefacts and an intriguing accumulation of bear skulls and bones. Petrographic study and U-series dating of a stalagmite and other calcite deposits in the cave provide an absolute chronological frame for the detrital infillings and their archaeological content and inform the environmental and climatic context of the cave evolution. Most detrital deposits in the cave were probably deposited before Marine Isotope Stage (MIS) 5 and the cave morphology and sedimentary deposits display current morphologies since ~135 ka. Consequently, the palaeontological and archaeological findings are older than ~135 ka. Calcite dated on and under the accumulation of bear skulls and bones suggests deposition during MIS 7. A first depositional contextualization of the bone accumulation does not allow us to discriminate between a natural or anthropogenic origin. The study emphasizes the added value of speleothem studies in archaeological sites and particularly in bringing a well-constrained chronological and environmental framework.  相似文献   

7.
A fragipan (Bxb horizon) encountered during the excavation of a multicomponent archaeological site buried on an alluvial terrace in central Pennsylvania was evaluated to determine the degree of development, pedostratigraphy, and age. Based on the horizon thickness, and the degree of development of adjacent horizons, we believe that the fragipan was weakly developed. Two to three buried A horizons (Ab) occurred within the Bxb, thus, the fragipan formed in a cumulative, or fluvent, type alluvial landscape and postdates the Ab horizons overprinted by it. The buried soils were associated with stratified cultural remains. Artifact and radiocarbon ages indicate that the fragipan formed in the last 4500 years. Fragipan-containing soils on alluvial terraces should be investigated for buried soils and associated stratified cultural remains overprinted by subsequent pedogenesis. © 1998 John Wiley & Sons, Inc.  相似文献   

8.
We present early to Mid‐Holocene paleo‐geographic reconstructions for the Ramore Head area (Northern Ireland). This coastal area is characterized by Mesolithic occupation (c. 10–6 ka) and preserved early–Mid‐Holocene peats both on‐ and offshore. This paper improves on previous reconstructions by employing a backstripping methodology, which removes accumulated recent deposits from identified buried paleo‐landsurfaces instead of using modern topography as an analogue to the past landscape. Paleo‐landsurfaces are identified offshore from seismic profiles supplemented by cores, and onshore through legacy borehole records. The paleo‐landsurface can be traced offshore to depths of −2 to −19 m and is buried by <5 m of modern sediment. It extends onshore under the coastal town of Portrush and is buried <2.5–10 m below modern ground level. The identified paleo‐landsurface is combined with sea‐level curves from recent Glacio‐Isostatic‐Adjustment models to reconstruct marine transgression during the early–Mid‐Holocene. Comparison is also made with reconstructions based on modern topography. Together, the identified paleo‐landsurfaces and revised reconstructions can assist future site prospection on‐ and offshore and delimit high‐potential areas for heritage management. Revised reconstructions also allow placement of extant archaeology into a more accurate context of landscape change and help develop insights into local‐scale site location patterns.  相似文献   

9.
The Amiens-Renancourt 1 site recently yielded one of the most important Upper Palaeolithic human occupations of northern France by the number of flint artefacts and especially by the presence of Venus figurines. All the material comes from a single archaeological layer located in a tundra gley bracketed by loess units. A multi-proxy study combining a detailed stratigraphy, luminescence and radiocarbon datings and high-resolution (5 cm per sample) grain size and molluscan analyses was therefore carried out to reconstruct and date the associated environmental changes and to determine the exact context of the human occupation. The chronological frame thus established supports the correlations of the archaeology-bearing tundra gley and of an underlying arctic brown soil with Greenland interstadials GI-4 and GI-3. Composition changes in the molluscan population enabled the identification of transitional and optimum phases and sub-phases within these two pedogenetic horizons. A conceptual correlation model linking molluscan phases with millennial-scale variations of Greenland ice-core and Sieben Hengste speleothem climate records is proposed. The Human occupation appears contemporaneous to the end of the stadial–interstadial transition of GI-3. Synchronous in Amiens-Renancourt 1 and Nussloch, subsequent micro-gleys may also result from a regional/global forcing. Such a level of detail is unprecedented in a loess sequence.  相似文献   

10.
This paper reports important findings relating to the chronology of Palaeolithic occupation, artefact typology and Quaternary fluvial deposits from a geoarchaeological watching brief undertaken over 17 years at Kimbridge Farm Quarry, Dunbridge, Hampshire. Sections were recorded and sampled and 198 artefacts, principally hand axes, were collected, with the primary aim of enhancing understanding of the geological context of the richest Lower Palaeolithic assemblage from Hampshire. Digital terrain modelling was used to characterize the three-dimensional form of the fluvial geology. Two gravel terraces have been confirmed: an upper Belbin Formation, which contained most of the archaeological artefacts, and a lower Mottisfont Formation. Results of specific note included recovery of artefacts demonstrating elements of ‘proto-Levallois’ technology from within the Belbin Gravel deposition. Fully developed Levallois technology was present across both the Belbin Gravel and the Mottisfont Formation at Dunbridge, the latter having an otherwise relatively sparse Palaeolithic content. Previously published OSL dating, supplemented by new data, has been combined with uplift modelling to suggest dates of MIS 9b and MIS 8, respectively, for these two gravels. This fits well with evidence from other sites in England and the near Continent for the timing of the earliest Levallois at around MIS 9. The results from the Dunbridge watching brief have demonstrated that this response provides a relatively cost effective method by which important scientific data can be salvaged from commercial quarrying.  相似文献   

11.
Bizat Ruhama, an Early Pleistocene site located in the southern coastal plain of Israel, has yielded a single archaeological horizon dating to the Matuyama chron. Recent technological and zooarchaeological studies suggest evidence of near in situ hominin occupations taking place in a semiarid climatic setting. Such an archaeological context is rare for the Early Pleistocene and must be corroborated through reconstruction of site formation processes. This paper offers a microstratigraphic view of the site based on results from a micromorphological and granulometric study aimed at reconstructing site formation processes. Results show that the bone and lithic specimens were deposited near their excavated provenience, in a depressed, seasonally waterlogged area, and were subsequently slightly displaced and buried by surface sediment. We infer that the Bizat Ruhama deposit represents one or a few hominin occupations taking place on the surface of an undulating inter‐dune depression under a semiarid Mediterranean climate. © 2010 Wiley Periodicals, Inc.  相似文献   

12.
The cliffed and active dune coastal region of Broome provides an excellent record of Pleistocene and Holocene stratigraphy of desert environments interfacing with the Indian Ocean. The Mesozoic Broome Sandstone is the basal stratigraphic unit in the area and is overlain by Pleistocene red desert quartz sand (Mowanjum Sand). Modern coastal processes of waves, wind and tide have resulted in distinctive sedimentary bodies (stratigraphic units) clearly linked to the sedimentary environment. The Mowanjum Sand, reworked by coastal winds, generates the landward-ingressing orange quartzose Churchill Sand, or reworked by waves and abraded to white sand with the addition of carbonate grains that form the beaches (Cable Beach Sand) and with eolian action, coastal dunes or inland-ingressing white dunes (Shoonta Hill Sand). These sedimentary bodies and stratigraphic units form a template with which to locate and interpret archaeological middens and Indigenous occupation over the past 5000?years in a context of coastal occupation, coastal stability, mean sea-level changes, climate changes, and availability of marine food and freshwater. Shell middens and stone artefacts form definitive layers or horizons in relation to the stratigraphy, in places in situ, and elsewhere reworked as sheets and plumes; understanding their inter-relationships has enabled the unravelling of the archaeological history and relating Indigenous occupation to biofacies and lithofacies. The array of sedimentary, biofacies and stratigraphic units are of national geoheritage significance in their own right. The addition of archaeological deposits as stratigraphic units provides a link between geoheritage and archaeology, where the archaeological materials are viewed as part of the complex stratigraphic story, part of the coastal history, and part of the geoheritage story.  相似文献   

13.
The cultivation of aroids (herbaceous plants with starchy corms) is the foundation of Oceanic societies, yet the study of prehistoric atoll agriculture (utilizing Cyrtosperma chamissonis) has been almost totally neglected. Aroid pit agricultural features, some measuring up to 100 m long and 20 m wide, excavated in the Marshall Islands (center ca. 8°N latitude, 170°E longitude) provide the first chronometric dates (1910 ± 70 B.P., Beta-79576) for this type of cultivation practice associated with coral atolls found throughout the Pacific. Excavations through an aroid pit cultivation pit rim identified a stratigraphic sequence beginning with the sterile subsoil, an A horizon deeply buried under pit spoil dirt, and a prehistoric midden deposit beginning below the surface A horizon. Granulometric analysis of sediments and identification of foraminifers documented the nearshore lagoon as the source for all non-cultural sediments. Anthropophilic land snails (Gastrocopta pediculus and Lamellidea pusilla) in the dated, buried A horizon is a firm basis for confirming the presence of humans near initial colonization (ca. 2000 B.P.) and anchors the culture-historical sequence for the long-term study of human impacts to low coral islands. Consequently, on-going analyses of plant opal phytoliths, starch grains, and charcoal from the buried A horizon, should document the nature of early atoll ecology prior to significant human modification. As aroid pit construction is associated, in many examples, with traditional property boundaries, detailed mapping and dating of these cultivation systems should relate to changes in land tenure and prehistoric social organization. © 1999 John Wiley & Sons, Inc.  相似文献   

14.
Recently, the sediment stratigraphy and geochronology of the well‐known Palaeolithic site Byzovaya in northern Russia were investigated. New technological analyses of the artefacts suggest a Middle Palaeolithic Mousterian culture, and occupation by Neanderthals, not Modern humans as previously thought. We present here a new and detailed documentation of the stratigraphy, including the geological context of the artefacts and faunal remains. From sedimentological criteria we confidently interpret the find‐bearing strata as debris‐flow deposits, covered by aeolian sediments. The chronology is based on radiocarbon and luminescence (OSL) dates from the find‐bearing and overlying strata. The results are utilized to reconstruct the geological history at the excavation area. The stratigraphy varies considerably across the excavation area. The most intact and undisturbed part of the sequence was found inside the most recent Excavation II. In this part the artefacts and bones appear to have been permanently sealed and protected by aeolian sand. The older Excavation I shows a more complicated stratigraphy, as the finds may have been temporarily exposed during the early Holocene owing to ravine incision and slumping activity. The individual radiocarbon dates that were collected from different parts of the site and from various stratigraphic positions are re‐investigated in this study. By using Bayesian statistics the conclusion is that the site was occupied during a restricted period around 30.6–34.7 ka. A series of partly unpublished OSL dates of coversand from different sites demonstrates a regional aeolian signal during the Lateglacial in northern Russia, 15–14 ka.  相似文献   

15.
Recent archaeological discoveries from exposures of the Cromer Forest-bed Formation at Happisburgh, UK, have radically changed interpretations of the nature and timing of early hominin occupation of northern latitudes, but this in situ archaeology is only one part of the picture. Surface finds of Pleistocene mammalian remains have been found along this coastline for centuries, with stone tools adding to this record over the past 7 years. The ex situ nature of these finds, however, means they are often seen as limited in the information they can provide. This work contributes to a growing body of research from a range of landscape and environmental contexts that seeks to demonstrate the value and importance of these ex situ assemblages. Here the focus is on Palaeolithic flint artefacts and Pleistocene mammalian remains recovered by a group of local collectors through systematic, GPS-recorded beach collection from 2013 to 2017, and their use in developing a methodology for working with ex situ Palaeolithic finds in coastal locations. The results demonstrate significant patterning that identifies unexplored exposures both onshore and offshore, considerably expanding the known extent of deposits and facilitating new insights into the wider archaeological landscape associated with the earliest occupation of northern Europe.  相似文献   

16.
The Jebel (Jebel is mountain in Arabic) Hamrat Fidan marks the “gateway” to the Feinan district of southern Jordan—one of the largest sources of copper during the prehistoric and Early Bronze Ages in the eastern Mediterranean. Preliminary excavations and surveys at sites along the Wadi Fidan have revealed a long history of settled occupation extending from the Pre‐Pottery Neolithic (ca. 6,500 B.C.) to early medieval times. Because of this long history of occupation, and the fact that this area was a regional center for the production of copper, the study of this area is important for understanding early metallurgy, craft specialization, and social evolution. During the summer of 1997, geophysical investigations at a series of Neolithic and Bronze Age sites identified specific areas within Wadi Fidan for future intensive excavations. Three geophysical techniques (electromagnetic induction, ground‐penetrating radar, and magnetometry) were used to help locate buried architectural and industrial features remaining from early mining and metallurgical operations, including copper ore bodies or voids. Geophysics was not used at the actual mining sites because of scheduling constraints; however, geophysics did delineate buried stone walls at three distinct Wadi Fidan sites. Magnetometry and ground penetrating radar provided little useful information. Buried stone walls were apparently “masked” by numerous magnetic stones on the ground surface making magnetometry useless. Reflections from known strata demonstrated that radar penetrated the ground adequately; however, known shallowly buried walls were not recognizable. Electromagnetic induction produced maps of linear and rectilinear features that suggested spatial distribution of widespread buried stone walls suitable for future excavation. A significant and unexpected finding was that electromagnetic induction proved capable of delineating buried stone walls. © 2000 John Wiley & Sons, Inc.  相似文献   

17.
Analysis of continuous core and drill cuttings from drill holes was compared and correlated to data obtained from bore hole geophysical logs to obtain subsurface stratigraphic information at the Lime Creek Paleoindian site, southern Nebraska. The analysis of these bore holes indicated that sedimentary layers and a significant buried soil horizon could be correlated throughout the preserved terrace fill at the site. Geophysical information obtained in well bores in 1993 was compared to lithologic and radiocarbon data from recent core holes and then integrated with archaeological profiles and artifacts collected between 1947 and 1950. A paleotopographic analysis of the soil horizon where the majority of the artifacts were discovered was then made. This ancient living surface was found to have developed on the banks of an abandoned channel, now deeply buried, that ran parallel to modern Lime Creek about 10,000 B.P. Paleoindian people likely camped on the banks of this channel, protected from cold northerly winds by a large bluff to the north of the site. © 2000 John Wiley & Sons, Inc.  相似文献   

18.
The processes of surface clast dispersal are discussed and it is shown that on flat land the spatial integrity of larger gravel clasts (which include most diagnostic artefacts) is likely to be preserved over long periods. A structured approach is described for predicting land surfaces where Lower Palaeolithic artefact scatters may have survived through the British Quaternary. The topographic map of Britain is subjected to three tests to eliminate areas unlikely to preserve these surfaces. After progressively subtracting glaciated areas, areas covered by superficial deposits, and river basins/areas with slopes steeper than about 2°, the surfaces remaining have the potential for long-term stability. Eight criteria are described to help verify true palaeosurfaces. They comprise mostly high level plateau lands. On to this map are plotted fifteen sample localities known to have yielded Lower Palaeolithic artefacts from surface contexts. Ten lie within the predictive model, the remainder belong to surface fluvial deposits or other superficial deposits. Four sites have been mapped in enough detail to show the distribution of individual artefacts; in three, traces of clustering occurs, suggesting the original scatter patterns have not entirely dispersed in time. The two sites of Warren Hill and the Northern Drift where the author has worked are examined in more detail. Comparison is made with a ‘pristine’ Early/Middle Stone Age surface site from arid terrain in Namibia. It is argued that in certain circumstances even in the volatile British climate surface scatters may not have moved far from their original location. The predictive map can only be a general guide: each site is different, but clay-with-flints has ubiquitous potential. Surface studies include both flint and quartzite artefacts, with their contrasting typologies. It is concluded that surface studies are likely to lead to a more complete understanding of early human occupation patterns.  相似文献   

19.
为有效解决地震解释中层位追踪的闭合,经岩芯、测井数据、速度资料、属性剖面、合成记录制作等分析,对滨参1井重新进行了地震地质层位的标定。与前人标定的结果比较,基底顶面T5反射时间由2 100 ms调整为1 843 ms;城子河组顶面T4-2的反射下调一个相位。依据本次标定结果新的解释方案,绥滨组 东荣组由原解释方案的全区分布改为局部分布,且向北有增厚趋势;对城子河组顶面埋深由1 692 m调整为2 246 m,城子河组厚度的计算也相应发生变化。  相似文献   

20.
茂名盆地为伸展作用下形成的半地堑式断陷盆地,油页岩发育于古近系油柑窝组和新近系尚村组中。油柑窝组油页岩与煤层伴生,分布在煤层顶部,是最主要的含矿层位,形成于半深湖相沉积环境。茂名金塘含矿区是油页岩富集成矿的中心区带,北西向断裂控制着油柑窝组和尚村组油页岩矿层的埋深、展布以及成矿过程。由于受到沉积环境和物质来源的影响,油柑窝组油页岩含油率一般为5％～9％,最高可达13％;尚村组油页岩含油率为3.5％～6.5％,平均为4.5％左右。  相似文献   

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