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1.
Palynology, radiocarbon dating, and open-section stratigraphies from archaeological trenches are used to examine the impact of human activity around the time of Norse landnám on vegetation and landscape associated with a small farm (Ø34) in the Qorlortoq valley, Eastern Settlement, Greenland (61° N 45° W). Peat deposits from a mire abutting the Norse ruins revealed a discontinuous palaeoenvironmental record containing a possible hiatus from ca. AD 410–1020. Palaeovegetational data were recovered either side of this period. Pollen assemblages suggest that open Salix scrub dominated the landscape during the pre-settlement phase. The later phases of landnám resulted in the creation of hay fields and heavily-grazed grassy heath. Site abandonment is reflected by a re-expansion of Salix. This occurs shortly before the onset of deposition of a Sphagnum peat, dated to cal AD 1420–1630 (2σ) and reflecting an increase in mire surface wetness, probably in response to a deteriorating climate. Radiocarbon dates were obtained on peat and plant macrofossils sampled from either side of the proposed hiatus at two different but closely-spaced (<20 m) locations across the mire. These produced significantly different dates for the cessation of peat formation in the pre-landnám period (cal BC 2130–1770 and cal AD 240–410 respectively), but near-synchronous dates for the recommencement of peat growth (cal AD 890–1150 for peat and a probably more reliable interval of cal AD 1020–1190 based on plant macrofossils). It is suggested that this hiatus may represent the first direct evidence for peat cutting in Norse Greenland.  相似文献   
2.
Diatoms recovered from archaeological features on a Viking Age farmstead excavation in the Mosfell Valley in southwestern Iceland are utilized as microscopic indicators of turf-based structures. Eroded turf can be difficult to distinguish macroscopically from naturally occurring sediments because turf foundations erode and melt into the landscape over time, leaving minimal evidence of site use. Turf was a principle building component in Iceland until the early 20th century. Turf strips and blocks were harvested from lowlands where organically rich peat and abundant water contributed to the development of bog plants with thick root mats that produced premium turf. Diatoms embedded in turf reflect the ecological conditions of the peat-bog at the time of deposition. Turf was cut from the bog and transported to higher elevations where drainage was more conducive to house construction. Siliceous diatom frustules are resistant to decay and preserve well archaeologically. The presence of diatoms in archaeological sediments is considered a marker of sediment provenience and an indication of human site use and anthropogenic modification of natural substrates. This paper demonstrates how diatom analysis can determine the presence and delimitation of archaeological features otherwise difficult to distinguish with the naked eye.  相似文献   
3.
As in traditional societies today ancient societies probably selected different fuels to meet specific heat requirements. Char and ash, the end products of fire, are often found in abundance in archaeological contexts. These end products can provide information regarding (i) the original fuel resource and type, (ii) the characteristics of the fire and (iii) combined with other archaeological evidence shed further light on possible socio-economic activity(-ies) associated with that fire. The three main fuel resources would have been (i) modern vegetation, (ii) fossil fuel and (iii) animal by-products. Local availability and abundance would have influenced the choice made.In this study an experimental approach was adopted to try and distinguish between the three different fuel resources that are known to have been used by ancient societies (and continue to be used by traditional societies today) from their char and ash remains to help determine original fuel-type and understand the relative heating properties. For this end one fuel-type from each fuel resource listed above, namely wood, peat and cow dung, was chosen.  相似文献   
4.
An experimental approach has been used to establish whether medieval ironworking activity could be identified in peat bogs using mineral magnetic measurements. The research project comprised three elements. First, magnetic susceptibility and remanence properties were obtained for materials from an experimental iron smelt, in a furnace of medieval design, and from material collected during the excavation of the medieval bloomery at Llwyn Du in Coed y Brenin, Snowdonia. Materials sampled and measured included charcoal, aerial dust, roasted bog ore and furnace dust. A second experiment determined whether small amounts of aerial dust released from the furnace could be detected in accumulating peat samples. This was achieved by sprinkling small quantities of dust on to a constructed ’peat core’ that had no detectable magnetic signature prior to the addition of the dust. The application rates used were within the range expected to fall on a peat bog located close to a medieval furnace. Thirdly, mineral magnetic measurements were made on a peat core collected close to the Llwyn Du bloomery. The results confirm that roasted bog ore, aerial dust released from and dust accumulating in the furnace after a smelt, are magnetically detectable. The aerial dust and roasted bog ore produced enhanced susceptibility and remanence signatures in the constructed ’peat core’ experiments. Peaks in IRM(0.88T) and HIRM were measured in the Llwyn Du peat monolith and appear to correlate with a time when the medieval bloomery was operational. The results presented here suggest that it is possible to identify evidence of past ironworking in peat bogs using mineral magnetic measurements and that the signatures remain well preserved in the peat record even after burial for several hundred years.  相似文献   
5.
Clay plates with stylized representations of birds found at Section VI of the Gorbunovo Peat Bog (Trans-Urals) in 1926 and 2009 are described here with regard to technology, typology, function, and age. Similarities with Suzgun and Late Cherkaskul artifacts (13th – 12th centuries BC) point to the date of the plates. Suzgun sanctuaries and Andronovo burial sites suggest that the site with which the plates are associated might be either ritual or memorial.  相似文献   
6.
This paper presents records of metal deposition as preserved by a peatland which has accumulated in the lowland coastal zone at Borth, near Aberystwyth, Ceredigion, mid-Wales, U.K. The research objective was to explore the origins and history of metal mining and (or) metallurgy by reconstructing a geochemical record of copper, lead and zinc pollution for the last four millennia. Two cores were extracted from Borth Bog, one from the raised ombrotrophic part of the bog and another from a minerotrophic part of Borth Bog close to the ancient copper workings at Llancynfelin. Although peat stratigraphy and nutrient status have influenced the geochemical record, the results suggest that an early phase of copper and lead pollution occurred at Llancynfelin whilst lead enrichment occurred in the peat core taken close to the centre of Borth Bog during the Bronze Age and the Roman occupation. Therefore the origins of copper and lead mining and metallurgy possibly extend back to the Bronze Age in central Wales. No record of historical pollution exists at either site. The results of this study also provide further evidence that lead and copper are immobile in ombrotrophic peat and that pollution records can be elucidated from minerotrophic peat. Zinc, however, may have suffered from post-depositional mobility.  相似文献   
7.
Mining in Falun, Sweden, was first mentioned in a deed from ad 1288, but previous studies of peat and lake sediments inferred that mining began during the fifth to eighth centuries. In order to reassess these findings, we performed new geochemical analyses on new samples from three key sites: Tisksjöbergets myr, a buried mire alongside the mine; Tisken, a small lake in Falun; and Runn, the main recipient for waters draining through Falun. At Tisksjöbergets myr, the peat contains up to 6% copper, giving it the characteristics of a cupriferous bog. Hence, this record is not useful for tracing early mining. The sediments of Tisken—upon which many of the old interpretations have relied—contain numerous cut wood fragments, and two of those gave young and reversed radiocarbon dates (19th and 16th centuries for 192 and 187 cm, respectively). This indicates that the sediment was derived from infilling and, thus, has little value as a historical record. Runn's sediment—the only reliable record—provides clear evidence of a rapid onset of large‐scale mining from c. ad 1245, with abrupt increases in ore‐related elements—for example, a 34‐fold increase in copper—this increase is consistent with the mid‐13th century burial of the mire at Tisksjöberget.  相似文献   
8.
Data from nine radiocarbon-dated pollen diagrams from the northeast of England are considered and it is argued that much of the area was deforested and used for farming during the late pre-Roman Iron Age. This farming continued throughout the Roman rule (approximately AD 80–AD 410) and lasted until at least the sixth century, implying a measure of political stability after the Roman withdrawal.  相似文献   
9.
The division of land on Dartmoor during the Bronze Age by the construction of moor-wide boundaries known as reaves represents a significant development in agricultural practice and land tenure. Previous research relating to the Dartmoor reaves suggests this way of life may have continued for no longer than 200–400 years. It has been suggested that their abandonment occurred as the result of a deteriorating climate, although there are no published palaeoclimatic reconstructions from the area. We therefore test the hypothesis that on Dartmoor, a marked climatic deterioration occurred in the late Bronze Age that can be linked to the abandonment of the reaves. A palaeoclimatic reconstruction derived from testate amoebae and peat humification analyses is presented from Tor Royal Bog, central Dartmoor, the first such record from southwest England. A major shift to a cooler and/or wetter climate is inferred from ca. 1395 to 1155 cal BC that is coincident with the period hypothesised as encompassing the abandonment. This climatic deterioration is replicated in sites in northern Britain, suggesting it was a widespread event. It is concluded that while the evidence supports a climatically forced retreat, there are a range of other socio-economic factors that must also be taken into consideration.  相似文献   
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