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1.
A marine electric resistivity survey was carried out over a submerged beach along the Agropoli shore (Salerno, Italy) to detect buried objects of archaeological interest below the sandy seabed. We found a shipwreck, a military vessel that probably sunk during the Salerno landing operations of the allied forces in the Second World War. Resistivity data provide information on the vertical and horizontal extension of the shipwreck, which is characterized by very low calculated resistivity values (about 2–5 ohm m). Such values differ significantly from the sand and the bedrock values (5–40 ohm m). Although the presence of the shipwreck is clearly visible from geoelectric data, the joint application of electric, magnetic and multibeam bathymetric techniques reduces the ambiguities inherent in each method. As shown in the Electrical Resistivity Tomography (ERT) and confirmed by the Digital Elevation Model (obtained from the processing of bathymetric data), the shipwreck extends more than 30 m in NE–SW direction and it is about 13 m wide. The global extension of the relic is consistent with the magnetic data, that are characterized by a magnetic anomaly with an amplitude of about 1800 nT and similar dimension, as inferred from the estimation of source boundaries obtained from the computation of the analytic signal. The results of our survey encourage the use of marine geoelectrical methods for the detection of buried archaeological targets, particularly in locations where the use of seismic prospecting is not effective (e.g. very shallow water with sandy sea-bottoms). The integration of different geophysical methods allows to better define the extension, depth and thickness of buried objects, suggesting that such an approach is the most effective for underwater archaeological investigations.  相似文献   

2.
In the present investigation, a geophysical study was carried out in the eastern flank of the Pyramid of the Sun to define potential continuations in this direction of a tunnel discovered beneath the western main entrance of this building. This man-made structure is one of the many extraction tunnels hollowed by the ancient Teotihuacans to obtain construction materials to build their city. Total field and high-resolution vertical gradient magnetic surveys were carried out. The spectral analysis of the total magnetic field enabled us to estimate the thickness of the alluvial cover over the basaltic flow as 3·3 m. It was also found that the main contribution to the observed magnetic field comes from the pyroclastic flow that covers the area of study. The horizontal gradient filter was applied to the low-pass filtered magnetic field to enhance magnetic contacts and structural boundaries. Inferred magnetic trends were related to fracture patterns within the basalts and pyroclasts, and low gradients provided an evidence of voids or tunnels. The Euler deconvolution method was applied as an attempt to confirm the above results. Using a structural index S=0, we determined the boundaries of main magnetic contacts as well as the interface between the basaltic flow and Las Varillas tunnel. Euler depths were found to range between 3 to 6 m, which represent the mean thickness of the basaltic flow.Two parallel ground probing radar (GPR) profiles were surveyed in the NW-SE direction. One passes on top of the known location of a tunnel (Las Varillas) and a second one 10 m to the north, approximately. The tunnel's roof is well outlined at depths between 3·5 and 4 m. On the other hand, little evidences of other buried tunnels or extensions of the known one were found. The second profile depicts a more complex morphology for the pyroclastic sheet. Anomalies related to basaltic flow or eruptive centres are clearly observed. Both profiles depicted the sedimentary base at 3 m, on average. A resistivity profile was undertaken along the first GPR profile. A resistivity image was obtained, that showed the vertical and lateral distribution of the true resistivity. High resistivity values were associated with the tunnel location (Las Varillas). Its geometry could also be inferred, its top is found at about 4 m and extends 20 m in the profile direction to the west. Unfortunately, the depth to its base could not be estimated, since profile length was too short. The sediment-pyroclastic flow interface could also be delimited at a depth of 3 m.Finally, a vertical magnetic field profile taken along the same surveyed line (GPR and resistivity) was inverted applying a two-dimensional algorithm. The initial model was estimated from GPR and resistivity interpretations. A simple model of Las Varillas tunnel was computed, which reasonably well satisfied geological and geophysical considerations.  相似文献   

3.
Recent sand quarrying operations for building and construction work in the eastern extremity of the Rub' al-Khali sand sea has revealed sediment exposures through a number of coastal and inland dunes. In the al-Daith district of Ras al-Khaimah (U.A.E.) a Holocene shell midden was exposed 2.8 m below the present dune surface interstratified between phases of Late Pleistocene and late Holocene dune sands. C14 and OSL ages constrain the site giving an insight into phases of landscape instability, dune formation, rates of sediment accretion, and a period of stability and human occupation. To date, Hafit period sites (5200–4500 cal BP) have been recorded in large numbers in the mountains and gravel plains of the Oman mountains. Coastal shell middens have not, as yet, been ascribed to the Hafit period from this part of the region and the study presents the first radiocarbon age from such a site. This study indicates the potential that many other sites exist elsewhere buried under late Holocene dune sediments and these provide an important insight into the development of the coastal landscape of this region.  相似文献   

4.
La Playa archaeological site in northern Sonora, Mexico contains a long record of human activity that includes the Paleoindian period (terminal Pleistocene) and much of the Holocene. The size and complexity of La Playa has discouraged a systematic characterization of its stratigraphy and geochronology, a deficiency we redress in the study. We distinguished seven stratigraphic units ranging in age from >44,570 to 400 cal yr B.P. using 14C dates from charcoal and terrestrial gastropods found mostly in archaeological features. All of the buried (in situ) cultural remains are contained in Units B (4690–1580 cal yr B.P.) and C (1010–400 cal yr B.P.) and represent overbank deposition from the nearby Rio Boquillas. Occupation at the site peaks in Units B4 and B5, corresponding to the Cienega phase (2800–1800 cal yr B.P.) of the Early Agricultural period. This period coincides with the growth of early agricultural villages in the region and is marked at La Playa by thousands of archaeological features including roasting pits, human burials, and extensive canal irrigation systems. The presence of semi-aquatic and aquatic snails demonstrates that water was present year round in the canal systems constructed during this period. Stable and radiometric isotopic evidence suggests that early agriculturalists diverted ground water over several kilometers from the nearby Rio Boquillas. The extensive Cienega phase occupation ended after about 1700 cal yr B.P. with deep erosion of the site, an event also visible in alluvial records in southern Arizona that marked the end of the Early Agricultural period and significant changes in settlement organization in the region.  相似文献   

5.
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   

6.
This paper is focused on the joint use of magnetometry and pole-dipole electrical resistivity geophysical methods for assessing their capability in the detection of a prehistoric site in the southwestern Jordan. The survey area, Auara, was built in the first century BC during the Nabataean time and is located in a very arid environment framed on the east and north by white sandstone hills. In order to test this site, a number of magnetic stations and two pole-dipole resistivity traverses were carried out in the investigated area. Magnetic data were taken with one sensor at height of 0.8 m along survey lines spaced 1 m apart. Resistivity measurements were carried out utilizing the pole-dipole array along two profiles. A total of 32 geoelectrical stations spaced 2 m were made along the two profiles. Magnetic method found structure with contrasting physical properties to those of the surrounding material. The archeological interpretation of such structure is in terms of rectangular cistern (pool) with dimensions 26 × 16 m. A probable location of two buried walls spaced 16 m are indicated by low resistivity values.  相似文献   

7.
Teeth of Homotherium latidens recovered from late Pleistocene sediments, Kents Cavern, England have long been the source of controversy. H. latidens is conspicuously absent from other late Pleistocene cave deposits in Britain, and is widely thought to have been extirpated from the region during the isotope stage 10 glacial period. Here we present high spatial resolution analyses of fluorine and uranium uptake profiles in teeth of three species from the same cave. The H. latidens tooth is clearly distinguished from the unambiguously provenanced Late Pleistocene hyaena and Middle Pleistocene cave bear teeth. These results are consistent with the theory that the H. latidens teeth originated at an exogenous location, were probably transported to Kents Cavern as Palaeolithic trade goods, and were buried in Kents Cavern in Palaeolithic times.  相似文献   

8.
This paper presents the results of a geoarchaeological study undertaken in Upper Egypt, in the western part of the Karnak Temples complex. The geoarchaeological approach helps to better understand the fluvial dynamics of the Nile in the proximity of the Pharaonic site during the late Holocene. Until recently, most researchers assumed that Karnak was built on a fluvial island and that a large basin connected to the Nile was built in front of the first pylon during the dynastic period. However, recent excavations conducted by the archaeologists of the Supreme Council of Egyptian Antiquities revealed a jetty or quay with probable direct access to the Nile. Therefore in order to reveal in more detail the landscape and waterscape changes in the most western part of Ancient Karnak, a palaeoenvironmental study was conducted. We studied several stratigraphic profiles, manual boreholes (maximum depth of 5.50 m) and percussion drillings (maximum depth of 25 m). Sedimentological and magnetic susceptibility analyses helped to characterize Nile River deposits and to identify the presence of aeolian deposits (associated with wadi fan deposits) in the lower part of the drillings. Fluvial dynamics characterized by flood events, sandy accretions and thick Nile silts/clay deposits are presented and discussed here for later palaeoenvironmental reconstruction. Accurate leveling of the different profiles and boreholes, together with a topographic survey, allow us to recover long sedimentological sequences and to correlate the different sedimentary units. Finally, in order to obtain a chronostratigraphic sequence, radiocarbon dates were obtained from wood, charcoal and ash samples (analyses undertaken at the laboratory of radiocarbon dating of Ifao, Cairo, Egypt). The presence of the Nile River in front of the first pylon in Karnak is attested from the end of the Second Intermediate Period (SIP, ca 1600 BC) until the end of Roman Times (ca. 350 AD), which both correspond to two main phases of Nile River floods.  相似文献   

9.
ALOS/PALSAR L-band full polarimetric data have been used to detect and characterize a well-defined geometric target hidden under sand deposits in the Western Desert of Egypt. This buried object is rectangular in shape with very straight boundaries and encloses an area of 500 m2. Inside the rectangular area there is a perfectly circular feature of approximately 53 m2 area. High and medium resolution optical satellite images (WorldView-2, ALOS/AVNIR-2) and field investigation confirm that the topography of the study area is relatively flat and completely covered by dry sand. The electromagnetic wave scattering behavior of the detected buried object was measured by decomposing the scattering matrix of ALOS/PALSAR full polarimetric data into Entropy-Alpha (H/α) and Freeman and Durden decompositions. Furthermore, a combination of unsupervised classification algorithms and Constant False-Alarm Rate (CFAR) edge detection was performed on the polarimetric data which revealed a well-defined geometric shape with straight borders. These borders have high α angles with low entropy, which physically means double bounce scattering mechanism with low randomness and is very similar to that of an urban scatterer, indicating that the detected target might be a buried wall-like foundation of a man-made structure. Moreover, 28 ground penetrating radar (GPR) profiles were acquired using a 270 MHz shielded antenna to validate the satellite radar remote sensing results. The GPR profiles reveal very clear hyperbolic shapes at 1.5 m depth with one of them showing a large hyperbolic shape-like structure, which might indicate the presence of a buried foundation. Thus the site might have significance to archaeological studies of the Western Desert, particularly previous human occupation and the sources of water for such habitation.  相似文献   

10.
Lichenometry is a method of dating that has been widely used in glaciated areas for determining the minimum age of exposure of a geomorphic landform during the late Holocene. This paper presents a regional calibration data set of lichen thallus sizes versus rock surface ages for the Huashan area, East China, based on measurements of yellow-green Rhizocarpon lichens on the known-age substrates at eight sites. An empirical relationship between thallus sizes and rock surface ages was established using both the traditional regression and the Bayesian approaches. Using the Bayesian calibration, the minimum age of the Huashan Grottoes was dated from 450 ± 60 to 330 ± 60 years ago, corresponding to the late Ming Dynasty (AD 1477–1632). These dates are generally consistent with those predicted from the regression-based linear growth curve. Our results suggest that applications of this technique can be safely extended to the non-glaciated areas.  相似文献   

11.
A distinctive sand layer enclosed within Holocene peat is described from Basta Voe, Isle of Yell, Shetland Isles. The sand layer, that can be traced considerable distances inland and up to a maximum altitude of c. + 9 m OD, is here interpreted as having been deposited by a former tsunami. AMS dating appears to indicate that the tsunami occurred between 1300 – 1570 cal years BP. At present, the tsunami has no known source mechanism although the most likely mechanism is thought to have been an offshore slump or slide. The available information would presently seem to indicate that this tsunami was restricted to the eastern coastline of Shetland. The relatively young age of this inferred tsunami is of considerable importance to planners and engineers concerned with estimating coastal flood frequency and magnitude.  相似文献   

12.
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   

13.
This study examines evidence for dental disease (caries, abscesses, antemortem tooth loss and severity of dental wear) in Nubian and Egyptian groups living in the Nile Valley during the New Kingdom. Specific attention is given to individuals buried at the site of Tombos, a cemetery in Nubia used during the Egyptian colonial occupation. In addition, three Nubian and two Egyptian samples are included for comparative purposes. While some similarities in condition frequencies between Tombos and the comparative groups are apparent, especially in the rates of caries and abscesses, significant differences in antemortem tooth loss and severity of tooth wear point to variation in these Nile Valley samples. These differences are especially evident for males. Higher rates of these conditions at Tombos may be attributed to the socio‐political and cultural changes taking place during this time of colonial occupation. Changes in foodways and occupational environments may have resulted in stress, as demonstrated by these dental conditions experienced by the Tombos people throughout this transitional period. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
Well constrained numerical ages of alluvial fan sediments are key to understanding the chronology of alluvial episodes and tectonic activity at the front of the Andean Precordillera. We tested the application of radiocarbon and optically stimulated luminescence (OSL) dating in the distal part of an alluvial fan five kilometers north of Mendoza. For OSL dating a large number of aliquots (n > 70) — each composed of ∼50 quartz grains — were measured in order to obtain reliable burial ages despite scattered dose distributions. Owing to a feldspar contamination in all samples, an infrared stimulation was inserted before each OSL measurement, which reduced the feldspar OSL signal successfully. By using the minimum age model we obtained stratigraphically consistent burial ages of alluvial deposits in a depth profile. The uppermost ∼1 m of sediment is composed of debris flow deposits buried 770±76 years ago. Three plant remnants used for radiocarbon dating from the same layer, however, yielded ages younger than 350 years, which are interpreted to underestimate the depositional age. Underneath the debris flow, a major unconformity cuts a series of distal alluvial fan sediments with interstratified floodplain deposits, which are composed of sandy and calciterich silt layers, respectively. Three samples from this unit which were distributed over one meter of sediment thickness yielded statistically concordant OSL ages of 12.3±1.2 ka, 12.3±1.2 ka, and 11.7±1.1 ka. The deposition of these sediments during the latest Pleistocene coincides with a phase of cool and humid climate, which occurred before the alluvial fan propagated farther into the foreland. The overlying debris flow sediments are associated with alluvial fan incision during the arid Late Holocene.  相似文献   

15.
Two equid species have been documented in the Pleistocene of the Iberian Peninsula, the horse Equus caballus, and the Eurasian hemione Equus hydruntinus. While the former survived the Holocene–Pleistocene until now, the timing for the extinction of the latter is unclear. Scarce, fragmented archaeological remains assess the presence of small equids living in the Holocene of Iberia. Those could possibly correspond to the Eurasian hemione although unambiguous morphological identification is often not possible. With the find of an equid tooth from Leceia, a Chalcolithic fortified site in Portugal, and using both morphological and mitochondrial genome analyses, we demonstrate for the first time the presence of a new equid species in Holocene Iberia, namely a donkey (Equus asinus). Radiocarbon dating of the tooth to Cal 2340–2130, and 2080–2060 BC with 95% probability, demonstrates that donkeys were present in Iberia well before the arrival of Phoenicians in the first quarter of the first millennium BC (900–750 years BC), which were considered so far as the first who introduced donkeys in the region.  相似文献   

16.
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   

17.
In the Pacific region, the onset of modern El Niño/Southern Oscillation (ENSO) activity at approximately 5000 years ago may have played a significant role in the development of cultures in the Pacific basin. Within Australia, similar trends in population and resource use have been identified but largely ascribed to cultural changes. To test human responses to changing ENSO activity through the Holocene we analysed a comprehensive suite of 710 radiocarbon ages from archaeological sites in ENSO-sensitive Queensland. We observe a dramatic and sustained increase in landscape activity at inland sites from 4860 ± 15 years ago, statistically indistinguishable from the timing of the onset of modern ENSO activity. Subsequent changes in long-term activity directly impacted on human populations indicating that once established, ENSO maintained a continuous influence on disparate cultures throughout the Pacific basin.  相似文献   

18.
Two adjacent chambers of the cave of La Chaise, Grotte de Bourgeois-Delaunay (B-D) and Grotte Suard, have been studied. Both were partly filled with detrital sediments containing lower and middle Palaeolithic artifacts and skeletal remains of pre-Neanderthalian hominids. Layers of stalagmitic calcite occur interstratified in the sediments of both chambers. Dates obtained by 230Th/234U ratios have provided a time scale for hominid and cultural evolution as represented in this cave.In B-D the lower travertine rests on a breccia containing cranial remains of juvenile Neanderthals. The base of the travertine dates to 151 ± 15 Ky (Ky = 1000 years BP); the top of the travertine yields a date of 112±5 Ky. The travertine contains pollen of an interglacial flora. Overlying detrital sediments 1·2 m in thickness contain artifacts transitional from Acheulian to Mousterian industries. They are capped by a travertine (Layer 7) whose base is dated at 100±6 Ky, and which is capped by stalagmites ranging in age down to 58±7 Ky. Overlying the travertine is sediment containing first Mousterian, and then Aurignacian artifacts.Near the base of the sediments filling Grotte Suard is a stalagmite layer dated to 249±30 Ky. It contains interglacial pollen and presumably dates to the beginning of the isotope stage 7 interglacial. Neanderthaloid hominid teeth and cranial fragments are found scattered through the overlying sediments, up to a capping stalagmitic layer whose base is dated at 101±7 Ky. The best described hominids from Suard are from a section that was probably overlying the capping stalagmite. The capping stalagmite is temporally correlated with layer 7 of B-D.  相似文献   

19.
With the research on the issue in its initial phases, the behaviour and hunting strategies of MSA communities inhabiting the Nile Valley in the Late and Terminal Pleistocene have been fragmentarily recognised thus far. Osteological materials from the area of the Affad Basin in the Middle Nile Valley, recorded in archaeological contexts and dated to the sixteenth millennium BP using OSL methods, have significantly enhanced our knowledge in this regard. It is the first time that an opportunity has occurred to construct a reliable model of the environment exploitation and the behaviour of human groups producing lithic tools using Levallois methods in the Terminal Pleistocene. Archaeozoological analyses have allowed the identification of taxa, species and anatomical origin of remains and enabled the establishment of a database of osteometric measurements. The animals hunted in the Sudanese Nile Valley during the Terminal Pleistocene have been classified with a view to refer the data to the results of analogous studies on MSA in South Africa. The behaviour of the communities occupying the Affad Basin 15,000 years ago was connected to the environment of the tree-covered, swampy savannah and extensive backwaters. Medium-sized antelope (kobus) was hunted most often. People hunted also, albeit less frequently, for large ruminants (buffalo), guenons and large rodents. Remains of fish and mega-fauna (hippopotamus and elephant) have been found in isolated concentrations, away from the camp sites. Remains of molluscs or ostrich eggs have not been registered. The condition of the osteological materials, notably their anatomical distribution, is shown to have been largely affected by wetland environment, rich in iron and manganese.  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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