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1.
The transformation of Rome during the Late Antiquity and the Early Middle Ages has been investigated by archaeologists and historians. Social and political changes are the main aspects which led to a progressive modification of the urban framework; abandonment, spoliation and transformation of buildings are quite diffused as documented by the archaeological literature. The consequence of these practices is a higher vulnerability of the buildings which, from the seismological point of view, played a main role in increasing the effects of seismic shaking. A number of earthquakes have struck Rome during the period of investigation (fifth to ninth century A.D.), known from historical sources: 443, 484–508, 618, 801, 847; in some cases (443, 484–508, 801) damage has been documented. In contrast, the archaeological sources characterise collapse layers and evidence of destruction at different sites with changing and not always conclusive chronological constraints. Consequently, collapse and destruction have been alternatively attributed to the above-mentioned earthquakes. Through a geoarchaeological and stratigraphic analysis of potentially coseismic collapse units, we want (1) to describe the archaeoseismic evidence derived from recent excavations and from the available literature (e.g. Piazza Madonna di Loreto, Piazza Venezia, Palazzo Valentini Crypta Balbi, Colosseo, Basilica Hilariana, Basilica di Santa Petronilla, Santa Maria Antiqua,…); (2) to discuss the chronological problems and the uncertainty of attribution of the collapse units to known historical earthquakes; (3) to discuss the earthquake damage exaggeration due to erroneous attribution of seismic origin to the evidence of destruction derived from archaeological data. Finally, we will infer the role that earthquakes may have had on the development of the urban landscape in the fifth to ninth century A.D.  相似文献   

2.
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   

3.
The geologic and geomorphic template of Grand Canyon influences patterns in the archaeological record, including sites where apparent increases in erosion may be related to Glen Canyon Dam. To provide geoarchaeological context for the Colorado River corridor and such issues, we explore first‐order trends in a database of field observations and topographic metrics from 227 cultural sites. The patterns revealed may be expected in other river‐canyon settings of management concern. The spatial clustering of sites along the river follows variations in width of the valley bottom and the occurrence of alluvial terraces and debris fans, linking to bedrock controls. In contrast, the pattern of more Formative (Ancestral Puebloan, 800–1250 A.D.) sites in eastern Grand Canyon and Protohistoric (1250–1776 A.D.) sites in western Grand Canyon does not follow any evident geomorphic trends. In terms of site stability, wider reaches with more terrace and debris fan landforms host a disproportionate number of sites with acute erosion. This links most directly to weak alluvial substrates, and the primary erosion process is gullying with diffusive‐creep processes also pervasive. Although Glen Canyon Dam does not directly influence these erosion processes, overall sediment depletion and the loss of major flooding leaves erosion unhampered along the river corridor.  相似文献   

4.
We describe a geoarchaeological survey of a 5‐km reach of the Rio Puerco channel and its tributaries, centered on the Guadalupe Ruin, a pueblo of the late 10th–12th centuries A.D. in north‐central New Mexico, with associated pollen, charcoal, micromorphological, and radiocarbon analyses. Severe erosion has drastically bisected the Puerco valley with four primary arroyos entering the western side of the Guadalupe reach of the valley: Tapia, Salado, Guadalupe and “No Name.” We recorded an 11‐m‐tall alluvial sequence marked by four phases of cumulic soil development, interrupted by six major periods of channel entrenchment that occurred at about 4100–3700 B.C. and 2900–2400 B.C., between 2200 B.C. and ca. A.D. 400, pre‐ and post‐ca. A.D. 900–1300, and in the late A.D. 1800s. Relative floodplain stability and associated cumulic soil development occurred prior to ca. 5700 B.C., between ca. 2600 to 2200 B.C. and A.D. 350 and 550, and ca. A.D. 900–1300. Multiple signatures of fires (oxidized sediment and charcoal) were observed in the Arroyo Tapia tributary sequence, especially in deposits dated ca. 6000 and 2600 B.C. These fires may have helped to enhance food resources for game animals by encouraging grass and shrub growth and/or to increase the growth of wild plants and eventually cultigens such as maize. Palynological evidence of maize in the Arroyo Tapia, dated ca. 2600–2200 B.C. may be the earliest thus far identified in the Southwest. © 2009 Wiley Periodicals, Inc.  相似文献   

5.
Wind erosion is a major problem for modern farmers, a key variable affecting nutrient levels in ecosystems, and a potentially major force impacting archaeological site formation; however, it has received scant consideration in geoarchaeological studies of agricultural development compared with more easily quantifiable environmental costs, such as vegetation change or fluvial erosion. In this study, soil nutrient analysis is used in the Kalaupapa field system, Moloka'i Island, Hawai'i, to detect an increase in wind erosion attributable to intensive agriculture following the burning of endemic forest. This practice began on a small scale in the 13th century A.D., expanded around cal A.D. 1450–1550, and continued until the near total abandonment of the fields after European contact in the 18th century. Nutrients that naturally occur in high amounts in coastal windward areas due to the long‐term, cumulative effect of sea spray were especially impacted. However, thanks to the unique landform of the Kalaupapa Peninsula, nutrient depletion in windward areas was offset by downwind enrichment and likely contributed to the long‐term sustainability of the system as a whole. Future research on tropical and arid agriculture should consider the cumulative environmental cost of increased eolian erosion attributable to anthropogenic landscape modification. © 2007 Wiley Periodicals, Inc.  相似文献   

6.
Underwater geoarchaeological research in Apalachee Bay, in the northeastern Gulf of Mexico off northwest Florida, has enabled the reconstruction of portions of the karst-controlled paleodrainage system, the discovery of several inundated prehistoric archaeological sites, and the exposure of sediments accumulated during the drowning of the continental shelf. Diagnostic artifacts discovered at the sites included chipped stone tools and debitage indicating Paleoindian, Early Archaic, and Middle Archaic occupation. A geoarchaeological model using terrestrial analogs was used to locate and investigate inundated sites. Methods employed include seismic profiling, vibracoring, diver tow surveys, diver collection transects, and induction dredge excavations. We document evidence for sea-level rise, related environmental succession and site formation processes for indundated prehistoric sites in the Apalachee Bay region from approximately 8000 to 6000 yr B.P. © 1997 John Wiley & Sons, Inc.  相似文献   

7.
In the absence of documentary evidence about settlement form and agricultural practice in northwest Scotland before the mid‐18th century, a geoarchaeological approach to reconstructing medieval land use and settlement form is presented here. This study applies multielemental analysis to soils previously collected from a settlement site in the Hebrides and highlights the importance of a detailed knowledge of the local soil environment and the cultural context. Geostatistical methods were used to analyze the spatial variability and distribution of a range of soil properties typically associated with geoarchaeological investigations. Semivariograms were produced to determine the spatial dependence of soil properties, and ordinary kriging was undertaken to produce prediction maps of the spatial distribution of these soil properties and enable interpolation over nonsampled locations in an attempt to more fully elucidate former land‐use activity and settlement patterns. The importance of identifying the spatial covariance of elements and the need for several lines of physical and chemical evidence is highlighted. For many townships in the Hebrides, whose precise location and layout prior to extensive land reorganization in the late 18th–early 19th century is not recoverable through plans, multi‐elemental analysis of soils can offer a valuable prospective and diagnostic tool. © 2007 Wiley Periodicals, Inc.  相似文献   

8.
An interdisciplinary non‐invasive research strategy combining the analysis of archival documents, detailed geomorphological mapping, Quaternary stratigraphic studies, analysis of ceramics, and radiocarbon dating was designed to reconstruct the evolution of the Mezimegeer–Juslibol Castle, northeastern Spain. This fortress had great strategic importance in the siege and conquest of the nearby Islamic city of Saraqusta by the Christians in A.D. 1118. The castle and moat complex was built in the mid‐10th century. In the mid‐12th century, its rapid degradation began, as it is shown by this geoarchaeological study of the sediments in the moats. Its present state of decay is due to later erosion that is promoted by the unstable bedrock of Miocene gypsum, highly deformed gravels that form a Pleistocene fluvial terrace, and the environmental aridity.  相似文献   

9.
Potshards discovered during excavation of bridge pilasters for a major expressway over the Rio Indio floodplain, a stream incised within the karsts of north‐central Puerto Rico, required large‐scale archaeological excavation. Five‐meter‐deep bridge pilaster excavations in the alluvial valley provide a 4500‐year history of deposition. Stratigraphic analysis of the exposed pilaster walls in combination with textural and organic carbon analyses of sediment cores obtained over a much broader area suggest a fluvial system dominated by overbank deposition. Six sequences of alternating light and dark layers of sediment were identified. The darker layers are largely composed of silts and clays, whereas the lighter layers are rich in sand‐sized sediment. Archaeological evidence indicates the organic‐rich dark layers, believed to be buried A horizons, coincide with pre‐historic occupation by Cedrosan Saladoid, Elenan Ostionoid, and Chican Ostionoid, extending from A.D. 450 to A.D. 1500. Lighter layers below the dark soil horizons are interpreted as overbank deposits from large magnitude flood events. The floodplain aggraded discontinuously with rapid deposition of sand followed by gradual accumulation of silt, clay, and organic material. An approximately 1‐m‐thick layer of coarse sand and gravel halfway up the stratigraphic column represents an episode of more frequent and severe floods. Based on radiocarbon ages, this layer aggraded between A.D. 1000 and A.D. 1100, which is well within the Elenan Ostionoid era (A.D. 900–1200). Rates of sedimentation during this period were approximately 8 mm per year, ten times greater than the estimates of sedimentation rates before and after this flood sequence. The cause for the change in deposition is unknown. Nonetheless the Elenan Ostionoid would have had to endure frequent loss of habitation structures and crops during these events. © 2003 Wiley Periodicals, Inc.  相似文献   

10.
Topographic maps are fundamental for geoarchaeological field studies and archaeological excavations. However, traditional methods of topographic mapping, as well as modern high‐tech methods such as airborne laser scanning and photogrammetry of high‐resolution satellite images, are often cost‐ineffective for field studies in terms of time, money, and labor. We here propose a method to measure topography for archaeological sites and surrounding areas quickly and accurately, using a laser range finder (LRF) and differential global positioning system DGPS. Three‐dimensional coordinates of points on land surfaces are measured through the LRF, targeted from multiple measuring locations whose positions are acquired with the DGPS. The point data are then interpolated to produce a digital elevation model (DEM) using a geographic information system (GIS). High‐resolution DEMs can be obtained with this method, with horizontal and vertical accuracies on the order of 10 cm. We here demonstrate the method for measuring detailed topography of the Hacituğrul Tepe in central Turkey. Digital topography data incorporated in GIS can also be part of an archaeological database, providing opportunities for quantitative analyses of topography and archaeological materials. © 2009 Wiley Periodicals, Inc.  相似文献   

11.
The Holocene was time of dramatic climate change in East Africa, shifting from wetter climate in the Early–Mid Holocene (∼10–5ka) to drier climates in the Late Holocene, followed by a slight reversal at <1ka. The Holocene was a time of cultural change from hunter‐gatherer and fishing to pastoralism. Recent excavations along the eastern shores of Lake Turkana, Kenya (4°N) provide new archaeological materials, a high‐resolution stratigraphic and paleoenvironmental data set, OSL dates, and cultural records in the context of documented environmental change (falling lake levels). Archaeological site FwJj25 (4.20 ± 0.28ka), on the northeastern margin of Lake Turkana, provides one of the earliest records of pastoralism in the region. The palimpsest record of FwJj5 (0.90 ± 0.06ka) was in a small valley containing a groundwater seep located 5km from the lake. FwJj5 reflects occupation by people who may have covered great distances in accessing resources, but were likely drawn to an environmental refugia of freshwater springs during times of regional aridity. © 2011 Wiley Periodicals, Inc.  相似文献   

12.
Numerical models are commonly used to estimate excavation‐induced ground movements. Two‐dimensional (2D) plain strain assumption is typically used for the simulation of deep excavations which might not be suitable for excavations where three‐dimensional (3D) effects dominate the ground response. This paper adapts an inverse analysis algorithm to learn soil behavior from field measurements using a 3D model representation of an excavation. The paper describes numerical issues related to this development including the generation of the 3D model mesh from laser scan images of the excavation. The inverse analysis to extract the soil behavior in 3D is presented. The model captures the measured wall deflections. Although settlements were not sufficiently measured, the predicted settlements around the excavation site reflected strong 3D effects and were consistent with empirical correlations. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

13.
Tell es‐Sâfi/gath is situated in the semiarid foothills of central Israel, adjacent to the coastal . plain. An enigmatic landscape feature, noted on aerial photographs, encircles the tell on three sides. This unique feature, unknown from other Near Eastern tells, was investigated. Methods of analysis include aerial photographs, field surveys, excavations, soil analyses, chronotypological ceramic classification, and radiocarbon dating. We concluded that (1) the peculiar landscape feature is a huge human‐made trench, over 2 km long, 5–6 m deep, and more than 8 m wide, cut through bedrock; (2) the trench was excavated during the Iron Age IIA (ca. 1000–800 B.C.E.), apparently as part of a siege system; (3) the extracted rock and soil material was dumped on the Iron Age landscape surface on one side of the trench, forming an elevated “berm”; (4) erosion processes transformed this landscape scar, as the trench filled with sediment; (5) stratigraphic analysis indicates two major phases of filling, separated by a period of landscape stability and soil formation (A horizon); (6) the two filling phases, exhibiting Iron Age IIA and Byzantine pottery (ca. 324—638 C.E.), appear to coincide with more intense human activity; and (7) the possible effect of climatic variations seems less obvious. © 2005 Wiley Periodicals, Inc.  相似文献   

14.
Geoarchaeological investigations in the Tonto Basin, Arizona provide insights into the Classic period Salado occupation from A.D. 1150 to 1450. Geomorphic reconstructions show that the Salado pursued irrigation agriculture on an intermediate Holocene terrace that was protected from flooding, while permanent settlements were located on stable Pleistocene landforms overlooking the field areas. Carrying-capacity-based calculations show that the population during the Classic period numbered in the low thousands. The development and subsequent cultural changes during the Classic period are tied to streamflow variations and cultural factors. The final abandonment of the Tonto Basin around A.D. 1450 is not the result of a major landscape change, but instead is linked to high frequency hydrologic variations that influenced food production coupled with cultural factors. © 1998 John Wiley & Sons, Inc.  相似文献   

15.
Recent investigations at the coastal spring site of Wawakiki in southern Perú have identified an intensive, late pre‐Hispanic agricultural production strategy along a sea cliff some 30 km north of the Ilo River. Excavations identified buried stone‐faced agricultural terraces underlying Spanish colonial and post‐colonial furrows, and long irrigation canals that transported water along steep hill slopes from inland springs. Depositional patterns, cultural debris, and calibrated radiocarbon age ranges suggest the site was farmed most intensively between A.D. 1200 and 1400, a period characterized by prolonged highland drought and recurrent El Niño–induced floods in southern Perú. Farmers transformed this arid coastal promontory into a productive agricultural landscape by exploiting multiple spring sources, steep canals, and stone‐faced terraces in an area where water is a very limited commodity and steep barren hills are highly prone to erosion. Furthermore, high‐relief terrain left much of the agricultural infrastructure well protected from periodic floods. © 2005 Wiley Periodicals, Inc.  相似文献   

16.
Geophysical reconnaissance in 1995 provided information useful in developing a successful strategy for the 1996 field season in resistivity mapping of subsurface cultural features at Talgua Village, an archaeological site in eastern Honduras. Ground truth excavations confirmed that high-resistivity anomalies detected by modified dipole–dipole apparent resistivity pseudosections correlate with a layer of small cobbles imported to fill low spots of this prehistoric settlement. Resistivity measurements reveal that mounds on this site were erected on normal subsoil, while at least one plaza was originally a topographic low that has been filled. The volume of imported stones is at least 500 m3, which represents a significant public improvement effort. Similar imported fill under the rest of Talgua Village could be mapped by similar means, and other prehistoric sites of the region could be geophysically tested for similar features. Resistivity profiles provide archaeologists with a quick, inexpensive, accurate, and noninvasive method of determining the extent of landscape modification at Talgua Village. © 1999 John Wiley & Sons, Inc.  相似文献   

17.
Geological analysis of 5–10‐m‐long sediment cores in the context of the anthropologically derived materials within them has allowed us to identify ancient landscape features in the Theban area around Luxor, Egypt. From these observations we propose a sequence of island formation and northwestward movement of the Nile from the Middle Kingdom onward in the area of the temple complexes of Karnak. The geoarchaeological techniques used appear to document the Holocene lateral migration and vertical aggradation of the Nile. Our method can be used to test postulated movements and is applicable to sites in river or coastal plains where sediments were being deposited during the occupation of the site. The sediments were sieved to retrieve sherds and numerous other small items (2 mm and larger), which included worked stone fragments, rootlet concretions (rhizocretions), desert polished sand grains, and occasionally beads. The small stone fragments can be correlated with buildings and sherds of known age within the site, while the rhizocretions and desert sand grains indicate environmental conditions prevailing at the time of deposition. © 2008 Wiley Periodicals, Inc.  相似文献   

18.
This paper presents the first systematic study of the vegetation history of a range of low hills in SW England, UK, lying between more researched fenlands and uplands. After the palaeoecological sites were located bespoke archaeological, historical and documentary studies of the surrounding landscape were undertaken specifically to inform palynological interpretation at each site. The region has a distinctive archaeology with late Mesolithic tool scatters, some evidence of early Neolithic agriculture, many Bronze Age funerary monuments and Romano‐British iron‐working. Historical studies have suggested that the present landscape pattern is largely early Medieval. However, the pollen evidence suggests a significantly different Holocene vegetation history in comparison with other areas in lowland England, with evidence of incomplete forest clearance in later‐Prehistory (Bronze?Iron Age). Woodland persistence on steep, but poorly drained, slopes, was probably due to the unsuitability of these areas for mixed farming. Instead they may have been under woodland management (e.g. coppicing) associated with the iron‐working industry. Data from two of the sites also suggest that later Iron Age and Romano‐British impact may have been geographically restricted. The documented Medieval land management that maintained the patchwork of small fields, woods and heathlands had its origins in later Prehistory, but there is also evidence of landscape change in the 6th–9th centuries AD. We conclude that the Blackdown Hills area was one of many ‘distinctive subregions’, which due to a combination of edaphic, topographic and cultural factors could qualify as an eco‐cultural region or ‘pays’. It is argued that the use of such eco‐culturally distinctive regions or pays can provide a spatial and archaeological framework for palaeoecology, which has implications for landscape research, designation and heritage management.  相似文献   

19.
The Fanta Stream site is an archaeological and paleontological locality in Addis Ababa, Ethiopia. The site contains a rich assemblage of fossil mammals and Acheulean artifacts of approximately 600 ka located in a rare high‐altitude context. A ground‐penetrating radar (GPR) survey was conducted in order to provide three‐dimensional imaging of the subsurface, which the authors use to interpret the geometry and distribution of fossil‐containing stratigraphic units. Utilizing the stream's natural cut bank exposure, we calibrate GPR data to known geologic units through radar facies analysis. Shallow, high‐amplitude coherent reflection geometries are attributed to volcanic tuff deposits, as these units exhibit subparallel continuous reflections consistent with planar stratified sedimentary deposition. Deeper, discontinuous reflection packages are interpreted as conglomeritic, fossil‐containing deposits. The results of the GPR survey outline the location of the Fanta Stream's paleodepositional features as well as suggest the extent of fossiliferous stratigraphic units for use in future excavations.  相似文献   

20.
Anthropogenic midden deposits are remarkably well preserved at the Neolithic settlement of Çatalhöyük and provide significant archaeological information on the types and nature of activities occurring at the site. To decipher their complex stratigraphy and to investigate formation processes, a combination of geoarchaeological techniques was used. Deposits were investigated from the early ceramic to late Neolithic levels, targeting continuous sequences to examine high resolution and broader scale changes in deposition. Thin‐section micromorphology combined with targeted phytolith and geochemical analyses indicates they are composed of a diverse range of ashes and other charred and siliceous plant materials, with inputs of decayed plants and organic matter, fecal waste, and sedimentary aggregates, each with diverse depositional pathways. Activities identified include in situ burning, with a range of different fuel types that may be associated with different activities. The complexity and heterogeneity of the midden deposits, and thus the necessity of employing an integrated microstratigraphic approach is demonstrated, as a prerequisite for cultural and palaeoenvironmental reconstructions.  相似文献   

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