scholarly journals Dating the Irrigation System of the Samarkand Oasis: A Geoarchaeological Study

Radiocarbon ◽  
2012 ◽  
Vol 54 (1) ◽  
pp. 91-105 ◽  
Author(s):  
Luca C Malatesta ◽  
Sébastien Castelltort ◽  
Simone Mantellini ◽  
Vincenzo Picotti ◽  
Irka Hajdas ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Numerical Model ◽  
Radiocarbon Dating ◽  
Overland Flow ◽  
Irrigation System ◽  
Archaeological Sites ◽  
New Approach ◽  
Sedimentary Deposits ◽  
New Evidence ◽  
Southern Flank

The oasis of Samarkand in the Middle Zeravshan Valley (modern Uzbekistan) was a major political and economic center in ancient western Central Asia. The chronology of its irrigation system was, until now, only constrained by the quality and quantity of archaeological findings and several different hypotheses have been proposed for it. We use a new approach combining archaeological surveying, radiocarbon dating, sedimentary analysis, and the numerical modeling of a flood event to offer new evidence for, and quantitative dating of, the development of irrigation system on the southern flank of the Middle Zeravshan Valley. We analyzed 13 bones and charcoals from 3 archaeological sites and obtained new 14C ages from Afrasiab (ancient Samarkand), a dwelling damaged by flooding in the 2nd century AD (site code: SAM-174) and the fortress of Kafir Kala. We established the origin of sedimentary deposits at the sites to infer the presence of the 2 most important canals of the southern flank: the Dargom and the Yanghiaryk. Finally, we show with a numerical model of overland flow that a natural flood was unlikely to have produced the damage observed at SAM-174. The combined results of the study indicate that the canals south of Samarkand existed, and were mainly developed, in the 2nd century AD and were not connected to the main feeding canal of Afrasiab at that time.

scholarly journals Dating the Irrigation System of the Samarkand Oasis: A Geoarchaeological Study

Radiocarbon ◽  
2012 ◽  
Vol 54 (01) ◽  
pp. 91-105
Author(s):  
Luca C Malatesta ◽  
Sébastien Castelltort ◽  
Simone Mantellini ◽  
Vincenzo Picotti ◽  
Irka Hajdas ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Numerical Model ◽  
Radiocarbon Dating ◽  
Overland Flow ◽  
Irrigation System ◽  
Archaeological Sites ◽  
New Approach ◽  
Sedimentary Deposits ◽  
New Evidence ◽  
Southern Flank

The oasis of Samarkand in the Middle Zeravshan Valley (modern Uzbekistan) was a major political and economic center in ancient western Central Asia. The chronology of its irrigation system was, until now, only constrained by the quality and quantity of archaeological findings and several different hypotheses have been proposed for it. We use a new approach combining archaeological surveying, radiocarbon dating, sedimentary analysis, and the numerical modeling of a flood event to offer new evidence for, and quantitative dating of, the development of irrigation system on the southern flank of the Middle Zeravshan Valley. We analyzed 13 bones and charcoals from 3 archaeological sites and obtained new14C ages from Afrasiab (ancient Samarkand), a dwelling damaged by flooding in the 2nd century AD (site code: SAM-174) and the fortress of Kafir Kala. We established the origin of sedimentary deposits at the sites to infer the presence of the 2 most important canals of the southern flank: the Dargom and the Yanghiaryk. Finally, we show with a numerical model of overland flow that a natural flood was unlikely to have produced the damage observed at SAM-174. The combined results of the study indicate that the canals south of Samarkand existed, and were mainly developed, in the 2nd century AD and were not connected to the main feeding canal of Afrasiab at that time.

An implicit scheme for simulation of free surface non-Newtonian fluid flows on dynamically adapted grids

2021 ◽  
Vol 36 (3) ◽  
pp. 165-176
Author(s):  
Kirill Nikitin ◽  
Yuri Vassilevski ◽  
Ruslan Yanbarisov
Keyword(s):  
Free Surface ◽  
Numerical Model ◽  
Newtonian Fluid ◽  
Viscoelastic Fluid ◽  
Fluid Flows ◽  
Numerical Results ◽  
Implicit Scheme ◽  
New Approach

Abstract This work presents a new approach to modelling of free surface non-Newtonian (viscoplastic or viscoelastic) fluid flows on dynamically adapted octree grids. The numerical model is based on the implicit formulation and the staggered location of governing variables. We verify our model by comparing simulations with experimental and numerical results known from the literature.

scholarly journals A New Radiocarbon Pretreatment Method for Molluscan Shell Using Density Fractionation of Carbonates in Bromoform

Radiocarbon ◽  
2010 ◽  
Vol 52 (3) ◽  
pp. 1301-1311 ◽  
Author(s):  
Christopher M Russo ◽  
Jennifer A Tripp ◽  
Katerina Douka ◽  
Thomas F G Higham
Keyword(s):  
Radiocarbon Dating ◽  
Separation Technique ◽  
Archaeological Sites ◽  
Density Fractionation ◽  
Pretreatment Method ◽  
Density Separation ◽  
Molluscan Shell ◽  
Archaeological Artifacts ◽  
Organic Remains

Coastal archaeological sites that lack organic remains for radiocarbon dating are often abundant sources of molluscan shells. As a substitute for materials such as bone and charcoal, shells can be analyzed with 14C dating to determine a site's age. Despite their being convenient, non-mobile archaeological artifacts, molluscan shells are plagued by several issues, including carbonate remodeling, in which aragonite in shells is converted to calcite as predicted by thermodynamics. We present here a carbonate density separation technique that addresses the issue of carbonate remodeling. Using a density fractionation with bromoform, aragonite concentrations are enriched in shells that have undergone significant remodeling. The technique has been applied to archaeological shells and has returned dates that are younger than those previously determined for the same shells.

Ramped pyroxidation: A new approach for radiocarbon dating of lime mortars

2021 ◽  
Vol 129 ◽  
pp. 105366
Author(s):  
Gerard Thomas Barrett ◽  
Evelyn Keaveney ◽  
Alf Lindroos ◽  
Colm Donnelly ◽  
Thomas Schrøder Daugbjerg ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
New Approach ◽  
Lime Mortars

scholarly journals Radiocarbon Dating of Calcined Bones: Where Does the Carbon Come from?

Radiocarbon ◽  
2009 ◽  
Vol 51 (2) ◽  
pp. 601-611 ◽  
Author(s):  
A Zazzo ◽  
J-F Saliège ◽  
A Person ◽  
H Boucher
Keyword(s):  
Radiocarbon Dating ◽  
Tooth Enamel ◽  
Skeletal Remains ◽  
Archaeological Sites ◽  
Carbonate Content ◽  
The Past ◽  
Mineral Fraction ◽  
Different Temperatures ◽  
C Value ◽  
Paleodietary Reconstruction

Over the past decade, radiocarbon dating of the carbonate contained in the mineral fraction of calcined bones has emerged as a viable alternative to dating skeletal remains in situations where collagen is no longer present. However, anomalously low δ13C values have been reported for calcined bones, suggesting that the mineral fraction of bone is altered. Therefore, exchange with other sources of carbon during heating cannot be excluded. Here, we report new results from analyses on cremated bones found in archaeological sites in Africa and the Near East, as well as the results of several experiments aiming at improving our understanding of the fate of mineral and organic carbon of bone during heating. Heating of modern bone was carried out at different temperatures, for different durations, and under natural and controlled conditions, and the evolution of several parameters (weight, color, %C, %N, δ13C value, carbonate content, crystallinity indexes measured by XRD and FTIR) was monitored. Results from archaeological sites confirm that calcined bones are unreliable for paleoenvironmental and paleodietary reconstruction using stable isotopes. Experimental results suggest that the carbon remaining in bone after cremation likely comes from the original inorganic pool, highly fractionated due to rapid recrystallization. Therefore, its reliability for 14C dating should be seen as close to that of tooth enamel, due to crystallographic properties of calcined bones.

Paleogeographic conditions of human habitation on the Karelian coast of the White Sea in the Late-Holocene (Chupa Town, Karelia, Russia)

The Holocene ◽  
2021 ◽  
pp. 095968362110417
Author(s):  
Shelekhova ТS ◽  
Lobanova NV ◽  
Lavrova NB ◽  
Rodionov GN
Keyword(s):  
Late Holocene ◽  
White Sea ◽  
Archaeological Site ◽  
Green Moss ◽  
Archaeological Sites ◽  
The White Sea ◽  
Diatom Flora ◽  
Ancient People ◽  
Human Habitation ◽  
New Evidence

Bottom sediments from Lake Pervoe Starushechye, on the White Sea shore, near Korabelnaya Bay, Chupa Town, 500 m from an archaeological site, were analyzed. The aim of our studies was to determine the position of the sea shoreline, to correlate archaeological sites relative to it, to date ancient settlements, and to reconstruct the paleoclimatic conditions and habitats of ancient people. Spore and pollen, diatom, and radiocarbon (14C) analyses were done. New evidence for the time of retreat of the seashore, the isolation of Lake Pervoe Starushechye from it and the time of the possible invasion of the area by ancient people was obtained. People were shown to inhabit the area from 3970 ± 120 to 3250 ± 120 14С y.a., when the sea shoreline reached modern levels of 19–22 m. The lake was then a ~8 m deep White Sea bay, in which marine gyttja was deposited. These events are reflected in the stratigraphy of the sequence and supported by the results of diatom and spore and pollen analyses. About 3500 y.a., mean annual temperatures in North Karelia were 2°С and annual precipitation ~50 mm/year higher than modern values. Spruce and pine-spruce forests with aspen and alder patches grew on the shore. A favorable climate and exuberant vegetation attracted people. Therefore, it is at the Atlantic-Subboreal boundary that the archaeological sites located at the above altitudes could arise. The lake separated from the White Sea 3020 ± 90 14С y.a. Freshwater sapropel was deposited in the isolated lake, as indicated by the composition of diatom flora and spore and pollen spectra. The sea shoreline declined to 17–16 m. Light-coniferous pine lichen-green moss forests with light-loving oligotrophic grasses were spreading actively throughout the study area.

Hominid carnivory and foraging strategies, and the socio-economic function of early archaeological sites

1991 ◽  
Vol 334 (1270) ◽  
pp. 211-221 ◽  
Keyword(s):  
Predation Risk ◽  
Foraging Strategies ◽  
Archaeological Sites ◽  
Olduvai Gorge ◽  
Marrow Fat ◽  
Density Dependent ◽  
Early Hominids ◽  
Competing Hypotheses ◽  
New Evidence ◽  
Economic Function

New evidence for the tissue types exploited by early hominids from carcasses possibly acquired through scavenging is derived from the larger mammal bone assemblages from FLK I, level 22 ( Zinjanthropus floor), and FLKN levels 1 and 2 from Bed I, Olduvai Gorge, Tanzania. Published skeletal part profiles from the two archaeological sites are evaluated using (i) modern observations on the sequence by which carnivores consume carcass parts in order to assess the timing of hominid access to carcasses, and (ii) measurements of flesh and marrow yields to assess the tissue types sought and acquired. These results suggest that the maximization of marrow (fat) yields, not flesh (protein) yields, was the criterion shaping decisions about carcass processing. Because of evidence for density-dependent destruction of some flesh-bearing parts by scavengers of the hominid-butchered assemblages, however, it is uncertain whether carcass parts were transported and acquired by hominids in a largely defleshed condition. The results on tissue types acquired are combined with a discussion of predation risk, feeding competition and the equipment needs of carcass processing in an attempt to identify archaeological test implications of competing hypotheses for the socio-economic function of the earliest archaeological sites.

scholarly journals Suitability of Ostrich Eggshell for Radiocarbon Dating

Radiocarbon ◽  
2001 ◽  
Vol 43 (1) ◽  
pp. 133-137 ◽  
Author(s):  
John C Vogel ◽  
Ebbie Visser ◽  
Annemarie Fuls
Keyword(s):  
Radiocarbon Dating ◽  
Archaeological Sites ◽  
Carbon Contamination ◽  
Suitable Material ◽  
Ostrich Eggshell

Ostrich eggshell from archaeological sites remains largely free of more recent carbon contamination and as such is suitable material for radiocarbon dating. The carbonate fraction of the shell does, however, display an initial deficit in 14C, which causes the ages to appear 180 ± 120 yr too old.

scholarly journals Age Discrepancies with the Radiocarbon Dating of Sagebrush (Artemisia Tridentata Nutt.)

Radiocarbon ◽  
2008 ◽  
Vol 50 (3) ◽  
pp. 347-357 ◽  
Author(s):  
Phil R Geib
Keyword(s):  
Radiocarbon Dating ◽  
Artemisia Tridentata ◽  
Ground Surface ◽  
Wood Charcoal ◽  
Western United States ◽  
Archaeological Sites ◽  
Fuel Wood ◽  
Tree Wood ◽  
Plant Remains ◽  
Age Discrepancy

When ancient hearths at open archaeological sites do not yield carbonized annual plant remains or other high-quality samples, wood charcoal is commonly used for radiocarbon dating. Sagebrush (Artemisia tridentata Nutt.), a shrub frequently used for fuel across much of the western United States, seems a potentially better candidate for 14C dating than tree wood since the possibility for significant age discrepancy might be less. A comparison of multiple assays from single features reveals that sagebrush can overestimate age more than even tree wood charcoal. A plausible cause of this appears to be persistence of the shrub on the ground surface for an extended interval after death, such that use as fuel almost invariably occurs hundreds of years after fixation of carbon. The potential for age discrepancy may decrease as population density increases because the demand for fuel wood would have resulted in a more rapid turnover of the fuel biomass. This is not true for Archaic period foragers of western North America when population levels were likely quite low and residential mobility quite high.

Sign in / Sign up

Export Citation Format

Share Document