ESTIMATION OF THE AGE OF A PRE‐INDUSTRIAL IRON SITE IN KOREA*

A pre‐industrial iron‐smelting site in Korea, whose period of active use is placed on typological grounds between the eighth and 18th centuries ad , has been dated using accelerator mass spectrometry and thermoluminescence. The ages of two charcoal samples were 77 ± 25 and 81 ± 25 years bp , with the calibrated date for both ranging from ad 1700 to ad 1955, while a clay fragment dated to ad 1650 ± 50. The results from typology and radiocarbon seem insignificant due to the considerable uncertainties involved, but in combination with the thermoluminescence result they place the most probable date of the site at around ad 1700.     

Early Holocene land snail exploitation in northern spain: the case of La Fragua cave

Abstract

The question of the anthropic or natural origin of land snail deposits within the archaeological record is the subject of debate all over the world. In the Cantabrian region of northern Spain land snail middens are routinely identified in the early Holocene archaeological record. La Fragua Cave (Cantabria, Spain), which contains an early Holocene layer dated to 9600±140 BP (10,932±196 cal BP), offers the opportunity to address this debate through the examination of Cepaea nemoralis (Linnaeus) land snails recovered in direct association with mammal bones, charcoal, lithic artefacts and other materials. It is therefore believed that their presence at the site is clearly anthropic in origin. In addition, the exploitation patterns indicate an occasional collection and consumption of land snails, which confirms the complementary character of these resources in the diet of hunter-gatherers in Cantabrian Spain during the Pleistocene-Holocene transition.     

THE ARCHAEOINTENSITY OF THE EARTH'S MAGNETIC FIELD RETRIEVED FROM PAMPEAN CERAMICS (SOUTH AMERICA)

Absolute intensity determinations using the Coe variant of the Thellier method have been carried out on some selected pottery fragments collected in the wetlands of the lower Paraná (Pampean region, Argentina) in order to construct the first archaeointensity master curve for South America. Associated radiometric ages range between 1640 ± 70 and 730 ± 70 bp . Twenty‐one samples (five fragments) out of 46 studied (eight fragments) provided successful absolute intensity determinations. The fragment‐mean archaeointensity values obtained in this study range from 21.9 ± 2.3 to 42.6 ± 5.4 μT, with corresponding virtual axial dipole moments (VADMs) ranging from 4.0 ± 0.5 to 8.1 ± 1.0 x 10²²Am². This corresponds to a mean VADM of (6.4 ± 1.8) × 10²² Am². The synthetic record retrieved from southern Argentina and Brazil consists of 17 mean archaeointensities distributed between approximately ad 700 and ad 1700. The data set shows several distinct periods of fluctuations of quite large intensity. However, most data are concentrated into a relatively narrow time period from ad 950 to ad 1300. Three general features may be detected: the time intervals from about ad 950 to 1130 and 1350 to 1480 are characterized by quite monotonic increases of geomagnetic intensity, while some decrease is observed from ad 1150 to 1280. These variations may be speculatively correlated to climate changes over multi‐decadal time scales. Important differences are observed between the data and the geomagnetic field predictions derived from recently reported global models, which reinforces the importance of regional reference curves for dating purposes.     

Luminescence dating of prehistoric hearths in Northeast Qinghai Lake and its paleoclimatic implication

Archeological research has been trying to provide evidence relevant to understanding both the timing of and processes responsible for human colonization of the Qinghai-Tibetan Plateau (QTP). Hearth is one of the most extensive, important, and typical prehistoric humanity activity evidence on the QTP. However, there are a number of hearths lacking charcoal material because of the wind and water erosion. Fortunately, most of these hearths can be dated by luminescence dating on the remnant sediments around the hearth. In this study, 18 optically stimulated luminescence (OSL) samples from 14 hearths in Yandongtai site (YDT) and Bronze Wire site (BW) in the northeast of Qinghai Lake area were systematically dated. The OSL ages range from 6.8 ± 0.7 to 14.4 ± 1.2 ka. There is a good agreement between OSL dating results and charcoal ages during the last deglaciation period, which indicates that OSL method has great potential in dating hearth on QTP. Combined with the previous dating results from other hearths, the age of hearths concentrates in 11–13 ka BP, i.e., the Younger Dryas (YD) chronozone. The increased number of hearths indicates reinforced colonization in the Qinghai Lake area during YD cold event, implying that the cold climate during YD event was not severe enough to hinder the inhabitation of prehistoric humanity at an elevation of 3.2 km.     

Radiocarbon measurements

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

OSL and TL characteristics of fine grain quartz from Mongolian prehistoric pottery used for dating

The OSL, post-IR OSL and pulsed post-IR OSL applied to polymineral grains and calculated by fitting to the data the contributions from fast, medium and slow components revealed that the polymineral samples under study are dominated by the medium component. An increase in D _e ’s with increasing integration intervals was observed, which is considered as an indication of increasing medium and decayed fast component; and the equivalent doses obtained using different components or minerals reflect also the shape of the dose distributions. The identified fast component in polymineral sample has photoionization cross section of 1.2±0.02 × 10^?17 cm². The present study shows the usefulness of the application of different luminescence techniques combined with fitting procedures as a check which should be adopted in dating protocols. Based on luminescence ages obtained on poly-mineral grains from prehistoric pottery samples from the Boroo settlement, Mongolia, which are in agreement with independent age control by ¹⁴C on charcoal material, it is argued that the manufacturing of Xiongnu — pottery at this site lasted until ca. 130±75 AD.     

Satellite image analysis of changes in glacier cover in Canada's northern Mackenzie Mountain Range (1987–2017)

The state of a group of glaciers in the northern Mackenzie Mountains across the Yukon‐Northwest Territories border was investigated over a period of three decades, using Landsat TM and OLI imagery from 1987, 1994, 1999, 2004, 2013, and 2017 to examine changes in glacier extents. A thresholded red/shortwave infrared band ratio image was used to delineate glacier boundaries. The total area of 74 glaciers in the study area decreased from 52.78 ± 1.32 km² in 1987 to 24.89 ± 0.62 km² in 2017, a loss of 27.89 ± 1.39 km² or 52.8 ± 2.6%, with a mean rate of reduction of 1.8% · a^?1. Smaller glaciers experienced larger relative changes in area. In this study, the rates of reduction are high compared to decreases reported for other glaciers in the region in the late 20^th century. Based on linear extrapolation of the trend in values of total glacier area, it is predicted—subject to uncertainties in how glaciers diminish in size and eventually disappear—that the study area could be free of visible glacier cover within three decades.     

RESEARCH REPORT: MAGNETIC INVESTIGATIONS AND THE AGE OF A MEDIEVAL KILN AT KUNGAHÄLLA (SOUTH‐WEST SWEDEN)*

The results from a magnetic survey and archaeomagnetic investigation of a medieval brick kiln at Kungahälla in Bohuslän (south‐west Sweden) are reported. Detailed magnetic total field and magnetic gradient measurements over known traces of the kiln showed marked local magnetic anomalies of up to 200 nT, revealing the rectangular shape of the kiln remains. Palaeomagnetic investigations of the remanent magnetization of 12 bricks from the kiln floor gave precise definitions of both the direction of the archaeomagnetic field [(D_m, I_m) = (66.7°, 8.8°), k = 655, α₉₅= 1.7°] and the palaeointensity [B_m= 69.0 ± 3.6 µT]. An archaeomagnetic date is obtained by comparing the direction of the archaeomagnetic field found in the kiln with a geocentral dipole‐transformation of the British master‐curve for secular variation. Of two possible archaeomagnetic dates (ad 1280 ± 50 or ad 1480 ± 50), the ad 1280 ± 50 age is in good accordance with the C‐14 ages and archaeological dates as well as with direct historical evidence, whereas a c. 100 years younger TL date appears to be too young.     

How the Romans got themselves into hot water: temperatures and fuel types used in firing a hypocaust

Abstract

The remains of hypocausts are noted as being widespread throughout the Roman Empire but, whereas the structure of hypocaust systems has been widely documented, primary knowledge of operating temperatures is limited. The petrographic technique of reflectance microscopy is used here to quantify cell wall reflectance values for charcoals from the hypocaust furnace of a bath suite forming part of small Romano-British villa complex at Groundwell Ridge near Swindon (Wiltshire, UK). The technique utilises material of archaeological origin to infer operating temperatures of the hypocaust furnace using established calibrations. The charcoals recovered from the furnace were identified as being predominantly Quercus (Oak) with some Populus/Salix (poplar/willow). Mean random reflectance of the samples indicated furnace-operating temperatures of 330–410°C. These temperatures fall below that of charcoal fuel production and hence suggest that it was wood that was used to fuel the hypocaust at Groundwell Ridge and not charcoal. Knowledge of the operating temperature of the furnace is a starting point in further calculations to understand, using primary evidence, the operating temperatures throughout the hypocaust system.     

Hydrothermal palaeofluid circulation in the fracture network of the Baksa Gneiss Complex of SW Pannonian Basin,Hungary

A well‐developed fracture‐filling network is filled by dominantly Ca‐Al‐silicate minerals that can be found in the polymetamorphic rock body of the Baksa Gneiss Complex (SW Hungary). Detailed investigation of this vein network revealed a characteristic diopside→epidote→sphalerite→albite ± kfeldspar→chlorite1 ± prehnite ± adularia→chlorite2→chlorite3→pyrite→calcite1→calcite2→calcite3 fracture‐filling mineral succession. Thermobarometric calculations (two feldspar: 230–336°C; chlorites: approximately 130–300°C) indicate low‐temperature vein formation conditions. The relative succession of chlorites in the mineral sequence combined with the calculated formation temperatures reveals a cooling trend during precipitation of the different chlorite phases (T_chlorite1: 260 ± 32°C →T_chlorite2: 222 ± 20°C →T_chlorite3: 154 ± 13°C). This cooling trend can be supported by the microthermometry data of primary fluid inclusions in diopside (T_h: 276–362°C) and epidote (T_h: 181–359°C) phases. The identical chemical character (0.2–1.5 eq. wt% NaCl) of these inclusions mean that vein mineralization occurred in a same fluid environment. The high trace element content (e.g. As, Cu, Zn, Mn) and Co/Ni ratio approximately 1–5 of pyrite grains support the postmagmatic hydrothermal origin of the veins. The vein microstructure and identical fluid composition indicate that vein mineralization occurred in an interconnected fracture system where crystals grew in fluid filled cracks. Vein system formed at approximately <200 MPa pressure conditions during cooling from approximately 480°C to around 150°C. The rather different fluid characteristics (T_h: 75–124°C; 17.5–22.6 eq. wt% CaCl₂) of primary inclusions of calcite1 combining with the special δ¹⁸O signature of fluid from which this mineral phase precipitated refer to hydrological connection between the crystalline basement and the sedimentary cover.     

Significance of diadematid echinoid ossicles in micropalaeontological samples,Miocene–Pliocene of Indonesia

Fragments of diadematoid echinoids from the early and middle Miocene, and late Miocene–Pliocene, respectively, of Java, Kalimantan and Sulawesi, Indonesia, are identified as diadematid spp. indet. (radioles from all sites) and Centrostephanus sp. (an interambulacral plate; early Miocene, Java). The radioles are probably a mixture of Diadema ± Centrostephanus ± Echinothrix. This is the first report of identifiable fossil diadematoid remains from Indonesia and demonstrates that these echinoids, so common in modern reef environments, were present in the Neogene of the region. Even though classified in open nomenclature, Centrostephanus sp. nevertheless provides further evidence for the Cenozoic record of a genus in which the only nominal species are of Late Cretaceous and Holocene age.     

The reflection of human activity in the sediments of Iwankowskie Lake from Subatlantic Phase (Polish Outer Carpathians)

The paper presents the analysis of organic and mineral sediments filling the depression, which developed over the landslide located at the slope (767–773 m a.s.l.) of Lubań ridge decscending to the Ochotnica river valley in the Polish Flysch Carpathians. The landslide formed in an early stage of the Subatlantic Phase (2490 ± 35 BP). The top of peat is dated at 1360 ± 50 years BP and is covered by 72 cm of clayey silts with some sandy intercalations, which indicate slopewash after deforestation. The pollen of ruderal plants and Cerealia (undiff.) reflect agricultural activity in the surroundings. The fragments of charcoal indicate the age of the forest clearance to the first half of the 17^th century. The late forest clearance at the elevated north exposed slopes followed 200–300 years later in relation to the foundation of the village at the valley floor.     

ESR and AMS-based 14C Dating of Mousterian Levels at Mujina Pećina,Dalmatia, Croatia

This paper presents the first chronometric dates for sediments that contain a Mousterian industry in Dalmatia (south Croatia). Electron spin resonance (ESR) dating was conducted on two teeth from the Mousterian level E1 at the site of Mujina Pećina. Additionally five bone and one charcoal sample from five different strata of origin at this site were dated by accelerator mass spectrometry (AMS). Assuming 30% moisture for both the gamma and beta dose rate calculations, the mean LU ESR age estimate is 44±5 ka for level E1, which is statistically indistinguishable from the mean EU ESR age estimate of 40±7 ka. A single, uncalibrated ¹⁴C age from the E1/E2 interface yielded an age estimate of 45,170 +2780/−2060 years bp while the mean of the five samples from overlying Mousterian levels is 39±3 ka. The true (calibrated) age of this mean is about 42 ka, which means that the entire stratigraphic profile in Mujina Pećina apparently was very rapidly deposited, and that the ESR age, regardless of uptake model is in good agreement with the calibrated ¹⁴C mean age. Temporally, Mujina Pećina overlaps with Pontinian Mousterian sites in west-central Italy and Vindija level G3 from northwestern Croatia. However, there are notable differences between the Mousterian industry from Mujina Pećina and these other sites. Collectively, the Croatian sites yield important evidence on the adaptation of European Mousterian people.     

Horticulturists and oxygen ecozones in the tropical and subtropical forests of Southeast South America

We analyse the isotopic values (δ¹³C, δ¹⁵N) of the diet of pre-Columbian horticulturalist populations from tropical and subtropical areas of southeastern South America, belonging to the Guarani and Taquara archaeological units. The data indicate different trends in each one (T?=?4.21; P?=?0.0004), showing a mixed diet with maize consumption in the Guarani samples (δ¹³C_co?=??15.5?±?1.8‰; δ¹³C_ap ?10.4?±?0.8‰) and a depleted one in the Taquara ones (δ¹³C_co ?18.2?±?1.7‰; δ¹³C_ap ?11.9?±?0.9‰), with a significant internal dispersion in both populations. The first population has higher nitrogen values (δ¹⁵N 11.1?±?0.6‰) compared to the Taquara samples (δ¹⁵N 9.3?±?1‰), suggesting a more carnivorous diet. The recognition of these pre-Columbian mixed diets involves the identification of maize cultivation on the Atlantic side of the southernmost area of South America (Parana Delta, 34° SL). Through the analysis of δ¹⁸O we have identified two isotopic ecozones, the first along the Paraná River Valley, with an average value of δ¹⁸O ?3.7?±?0.5‰ (CV?=?13.5%; CI?=??3.83 / ?3.16), and the second one, located in the Planalto of southern Brazil (Araucaria Forest), with a mean value of δ¹⁸O ?1.5?±?0.3‰ (CV?=?16.5%; CI?=??1.69 / ?1.29). The isotopic data (δ¹³C, δ¹⁵N and δ¹⁸O) suggest human movements between these two ecozones.     

ARCHAEOMAGNETIC TILT CORRECTION ON BRICKS

Fired bricks are used in archaeomagnetic work to determine the Inclination I of the earth's magnetic field at the time of firing. However, in addition to the usual mean error of between ± 1/2° and ± 2° due mainly to inexact levelling of the bricks during the firing, there is a systematic error in the measured mean value of the Inclination that may amount to 2° or 3° at high magnetic latitudes (I? 80°), while at lower magnetic latitudes (I< 60°) it is usually less than 1/2°. A method of correction based on the measured statistical spread of the bricks is suggested.     

The use of reflectance values for the interpretation of natural and anthropogenic charcoal assemblages

Charcoal assemblages occur in both natural and archaeological settings. Cell wall reflectance values of charcoal in polished blocks under oil provide a proxy for temperature of formation. This paper aims to (1) determine whether wildfire charcoals and anthropological charcoals from various pyrotechnical activities can be distinguished using reflectance data and (2) establish if re-charring (i.e. use of charcoal fuel) can be recognised in the archaeological record through analysis of laboratory-produced re-charred charcoals and charcoals from an experimental iron smelt and traditional bronze casting which utilised charcoal fuel. Reflectance frequency data from assemblages representing burning of charcoal, in this case of iron smelting and bronze casting, indicates temperatures from above the mean value of charcoal production (>475°C) up to the maximum temperature reached in the subsequent process (i.e. >475 to >1,100°C). In contrast, wildfire charcoals showed a range of values including material with barely measurable reflectance (minimum values from 0.06% to 0.56%Ro) to maximum reflectance values varying from 1.65%Ro (Tilford) to 3.8%Ro (Zacca). The mean wildfire reflectance indicated temperatures in the range 325–400°C, which can therefore clearly be distinguished from that of the charcoal burning processes. The laboratory-produced re-charred charcoals take on the reflectance value of the highest temperatures experienced; reflectance values were not constrained by the original temperature of formation. High temperatures are most easily achievable by the burning of charcoal fuel, and hence high reflectance charcoals are likely to represent re-charred charcoal. Therefore, this quantitative reflectance method can be used in archaeology to determine the minimum temperature of formation of charcoals in anthropological processes which involve fire, can indicate the likelihood of use of charcoal or wood as fuel and can distinguish between an assemblage of high temperature anthropogenic charcoals and charcoals formed from natural wildfire.     

Vegetation,land, and wood use at the sites of Bat and Al‐Khashbah in Oman (fourth–third millennium BC)

About 4200 charcoal fragments have been identified from the fourth‐ to third‐millennium BC archaeological sites of Bat and Al‐Khashbah in order to gain an understanding of plant resources available at the sites. Acacia sp., Ziziphus sp., and Tamarix sp. were the main taxa identified at both sites and indicate a similar vegetation composition as today. Phoenix sp. (date palm) charcoal also has been found at both sites. Whereas the cultivation of date palm for the 2700–2300 BC layers from Bat was likely, given other circumstantial evidence (i.e. local cereal cultivation and floodwater irrigation), it is unclear whether date palm was cultivated at Al‐Khashbah. Especially for the older periods (3300–2700 BC) it is possible that nomadic pastoralists were exploiting and/or managing wild date palms. The find of Avicennia marina at Al‐Khashbah indicates long‐distance contacts with the coast.     

An otological investigation of Lithuanian skulls

Two thousand seven hundred and sixty temporal bones from 1603 skulls ranging from the Neolithic to the eighteenth century AD were investigated visually and under magnification, scoring auditory exostoses, stapes footplate fixation and removing preserved auditory ossicles. Sixteen cases of auditory exostoses were noted. Changes in their occurrence were evident in adult skulls from the first to second millennia AD, (3.31 ± 0.87 per cent and 0.25 ± 0.18 per cent, p < 0.001). Clear sexual differences were also elucidated (males: 1.96 ± 0.56 per cent, females: 0.49 ± 0.28 per cent). Taking into account the geographical latitude of Lithuania, this prevalence should not be considered high. Twelve cases of stapes footplate fixation in the oval window, which could be considered as otosclerosis, were identified; no sexual or temporal differences were noted. The general frequency in adult skulls (0.99 ± 0.28 per cent) is similar to that in contemporary Caucasoid people. Three hundred and four intact auditory ossicles obtained during examination were measured. As these measurements did not differ significantly from data in the literature, morphological stability of the auditory ossicles was confirmed. Certain sexual differences were established for several measurements.     

Dendrochronological and radiocarbon dating of the medieval stronghold in Ujście (Poland)

In 2008, the archaeological museum in Piła carried out excavations in the site No. 5 in Ujście upon the river Noteć (Poland), at the Rybacka Street and in the Old Market Square. In 12 archaeological excavations and 4 surveys abundant wooden structures were discovered, from which about 800 samples were taken, mainly of pine (Pinus sylvestris L.) and oakwood (Quercus sp.). The studies were aimed at absolute dating of wood with the dendrochronological method, the wiggle matching fitting curves method, as well as anatomical determination of wood. Absolute dating of the oakwood from the Rybacka Street allowed to distinguish the oldest fortifications of the stronghold from the ninth century, and also intensive introduction of wood in the years 980–1080 AD, whereas analysis of wood from the Old Market (survey IV) allowed to distinguish eight structural levels, from the 1530s until the 970s. On the basis of the pine wood 227-year-long local chronology 2U_02A was produced, dated with the wiggle-matching method for the period 860–1080 (±10) cal. AD. Most of the pine samples proved to represent wood introduced in the 990s and 1040s (±10) cal. AD, and also some repairs in the years 1000–1030 and 1050–1070 (±10) cal. AD.     

Quantifying woodland resource usage and selection from Neolithic to post Mediaeval times in the Irish Midlands

The antiquity and context (site or feature type) are the two principal factors that act as a framework for interpreting charcoal and wood data from archaeological sites in the recreation of past woodland environments. This research addresses these parameters through the analysis of over 18,000 charcoal fragments from 57 archaeological excavations carried out along a 61?km road scheme in the midland region of Ireland. Observations on spatial vegetation dynamics and woodland resource patterns are also reported on. The data were analysed through percentage frequency and multivariate analyses. The results reveal woodland resource usage in terms of wood types selected for use as fuel or as structural wood as well as patterns of change and variability in taxonomic composition in relation to site types, feature types and time periods. Selection was found to be low in prehistoric times and in particular at burnt mound sites/fulachta fiadh but became increasingly important as time progressed. This has important implications when charcoal from archaeological settings is used in environmental reconstructions.