100 research outputs found
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Change is good: adapting strategies for archaeological prospection in a rapidly changing technological world
Ye
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The Schlumberger Array in geophysical prospection for archaeology.
The Schlumberger array, or Schlumberger, was one of the first
resistance arrays to be used to detect buried archaeological
features. The early work used fixed probes and widely spaced
traverses. Recent simulation work, Ăœhowever, suggested that
the array should give improved resolution and depth
penetration over the Twin-Probe array. This thesis is an
attempt to operationalise the Schlumberger for use in
archaeological prospection. This has been achieved via a
co-ordinated use of laboratory simulation and-field studies.
Initial fieldwork in England suggested. that the. - use of
point electrodes created response patterns that were
dependent upon the relative direction of linear targets. This
was verified using a simulation tank modified to represent
field procedure. The recognition of this response, therefore,
required each survey area to be surveyed twice. The re-survey
requires the two current probes to be positioned at right
angles to the original survey points.
The Schlumberger was then used in a battery of methods to
investigate the problem of the archaeological interpretation
of- small, discrete scatters of ceramic sherds that cover the
landscape in Greece. The research has indicated a variation
of intra-site patterning that may be significant to the
function of these sites. Overall, the results suggest that
the relationship between the 'site' and its environment is a
complex one, one that can be oversimplified when the ceramic
evidence is viewed in isolation. The Schlumberger indicated
possible structural elements within some of these sites
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Preparing for the future: A reappraisal of archaeo-geophysical surveying on Irish National Road Schemes 2001-2010
yesThis document reviews Legacy Data generated from 10 yearsâ worth of road scheme activity in
Ireland to determine how archaeological geophysical surveys could be carried out on national
roads in the future. The geophysical surveys were carried out by several different contractors
across a range of challenging field conditions, geologies, weather and seasons. The research is
based upon the results of linear schemes but also has validity for wider approaches. The
findings of this research are based upon the compilation of all terrestrial archaeological
geophysical surveys carried out on behalf of the National Roads Authority (NRA), a review of
the success or otherwise of those surveys in comparison with ground-observed excavations and
in combination with experimental surveys that tested previously held assumptions or
knowledge to determine best practice methods for the future.
The use and success of geophysical surveys in Ireland differ quite significantly from those in the
UK, from where many of the methods of assessment were derived or adapted. Many of these
differences can be attributed to geology. Ireland has a very high percentage of Carboniferous
limestone geology, overlain mostly by tills and frequent occurrences of peat. These soils can
reduce, to some extent, the effectiveness of magnetometer surveys; the most frequently used
geophysical technique in Ireland. However, magnetometer data can be maximised in these
cases by increasing the spatial resolution to produce effective results. An increase in spatial
resolution is also effective generally, for enhancing the chances of identifying archaeological
features by discriminating between archaeological and geological anomalies as well as
increasing anomaly definition and visualisation of small and subtle archaeological features.
Seasonal tests have determined that Irish soils are generally suitable for year round earth
resistance assessments although some counties in the southeast of the country may experience
very dry soils at the surface during some periods of the year.
A variety of sampling strategies were used in the past, however it is now apparent that detailed
assessments across the full length and width of a proposed road corridor are the most
appropriate form of geophysical investigation. Magnetometer surveys are generally suitable for
most Irish soils and geologies, although exceptions apply in areas of near-surface igneous
deposits, deep peat and alluvial soils; however magnetometer surveys are not capable of
identifying all types of archaeological features and other methods will be required for a full
evaluation.
Analysis of the Legacy Data has determined that in general the NRA archaeological geophysical surveys were historically used in a very positive way on road schemes. The range of features
assessed or identified account for most types of archaeological sites in Ireland. These have
provided a significant archive of case studies that will be of benefit to future archaeological
geophysical research and will help to protect the globally dwindling archaeological resource
that is threatened by development-led or commercially driven projects
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BradPhys to BradViz or from archaeological science to heritage science
YesArchaeology is a broad church and its role as a âtwo cultureâ discipline is frequently cited. This position at the interface of the arts and sciences remains central to archaeological activity but there have been significant changes in the structure of archaeology and its relationship to society overall. The growth of heritage science, in particular, is driving change and development within archaeology at a national and international level. This paper discusses these developments in relation to the author's own research trajectory and discusses the significance of such change
Unveiling the prehistoric landscape at Stonehenge through multi-receiver EMI
YesArchaeological research at Stonehenge (UK) is increasingly aimed at understanding the dynamic of the wider archaeological landscape. Through the application of state-of-the-art geophysical techniques, unprecedented insight is being gathered into the buried archaeological features of the area. However, applied survey techniques have rarely targeted natural soil variation, and the detailed knowledge of the palaeotopography is consequently less complete. In addition, metallic topsoil debris, scattered over different parts of the Stonehenge landscape, often impacts the interpretation of geophysical datasets. The research presented here demonstrates how a single multi-receiver electromagnetic induction (EMI) survey, conducted over a 22 ha area within the Stonehenge landscape, offers detailed insight into natural and anthropogenic soil variation at Stonehenge. The soil variations that were detected through recording the electrical and magnetic soil variability, shed light on the genesis of the landscape, and allow for a better definition of potential palaeoenvironmental and archaeological sampling locations. Based on the multi-layered dataset, a procedure was developed to remove the influence of topsoil metal from the survey data, which enabled a more straightforward identification of the detected archaeology. The results provide a robust basis for further geoarchaeological research, while potential to differentiate between modern soil disturbances and the underlying sub-surface variations can help in solving conservation and management issues. Through expanding this approach over the wider area, we aim at a fuller understanding of the humanâlandscape interactions that have shaped the Stonehenge landscape
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Magnetic geophysical mapping of prehistoric iron production sites in central Norway
YesThe slag pit furnace of the TrĂžndelag tradition for iron production is a very specific cultural-historical
tradition in central Norway in the Early Iron Age, but few of these iron production sites have been
excavated in their entirety and there is therefore a lack of information about their size, spatial layout
and organisation in the landscape. The aim of this paper is therefore to investigate how magnetic
geophysical methods can be used as a way of locating, delimiting and characterising activity zones
and specific archaeological features associated with this tradition of iron production. The NTNU
University Museum in Trondheim performed geophysical surveys of four different iron production
sites, combining topsoil volume magnetic susceptibility measurements and detailed fluxgate
gradiometer surveys. Analysing and comparing the survey results with sketches and topographic
survey results, as well as comparable geophysical survey data from iron production sites elsewhere
in Norway, made it possible to gain new and valuable cultural-historical and methodological
knowledge. The topsoil volume susceptibility measurements revealed a strong contrast between
the main production areas and the natural background measurement values, often in the range of
7â27 times the median background values. The absolute highest measured values were usually in
the area closest to the furnaces, and within the slag mounds. Satellites of high readings could be
interpreted as roasting sites for iron ore, and even areas with known building remains related to the
iron production sites had readings stronger than the median. The fluxgate gradiometer data helped to
characterise individual features further, with strong geophysical contrast between features within the
iron production sites and the areas surrounding them. Also, by analysing their physical placement,
geophysical characteristics such as contrast, magnetic remanence and size, it was possible to gain further insight into the spatial organisation by indicating the potential location of furnaces, the
spread of slag and the handling of iron ore. The latter involved both where the roasted iron ore was
stored and where it was roasted. The geophysical characteristics of the furnaces were less uniform
than situations reported elsewhere in Norway, which can be explained by the reuse of furnaces and
slag pits. The spread of highly remanent material in and around the furnaces and elsewhere within
the limits of the iron production sites also created a disturbed magnetic picture rendering it difficult
to provide an unambiguous archaeological interpretation of all the geophysical anomalies identified.
In conclusion, these results showed that the geophysical methods applied made it possible to indicate
the physical size, layout and internal spatial organisation of iron production sites of the TrĂžndelag
slag pit furnace tradition
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Cityscapes without figures: geophysics, computing and the future of urban studies
Ye
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EAC Guidelines for the use of Geophysics in Archaeology: Questions to Ask and Points to Consider.
These guidelines provide an overview of the issues to
be considered when undertaking or commissioning
geophysical survey in archaeology. As every project diff ers
in its requirements (e.g. from fi nding sites to creating
detailed maps of individual structures) and variations in
geological and environmental conditions lead to diff erent
geophysical responses, there is no single âbestâ survey
technique or methodology. Th is guide, in its European
approach, highlights the various questions to be asked
before a survey is undertaken. It does not provide recipebook
advice on how to do a geophysical survey or a tick
list of which technique is suitable under what conditions.
Experienced archaeological geophysicists should be
consulted to address the questions that are being posed.
Using geophysical techniques and methods inappropriately
will lead to disappointment and may, ultimately, result
in archaeologists not using them at all. âIf all you have is
a hammer (or magnetometer), driving a screw becomes
impossibleâ.
Especially in the American literature the term âremote
sensingâ is oft en used to describe geophysical as well as
air and space based exploration of underground features
(e.g. Wiseman and El-Baz 2007). By contrast, and in line
with European traditions, a clear distinction is made
here between ground-based geophysical techniques and
remote sensing techniques. Th is is based on the imaging
principles underlying the respective technologies. Ground
based systems usually collect one spatially registered data
sample from each sensor location (e.g. a single reading
for each magnetometer, or a single trace from each GPR
antenna). Remote sensing techniques, by contrast, collect
spatially resolved data from a whole area of investigation
from each sensor location, using either the systemâs optical
aperture (e.g. photography) or a scanning device (e.g. laser
sampling).
These guidelines are based on the experience of the authors
in archaeological geophysics and infl uenced by various
published sources
Methods to Assess Subcellular Compartments of Muscle in C. elegans
Skeletal muscle is essential for locomotion and is the bodiesâ main protein store. Muscle health measurements within C. elegans are described. Prospective changes to muscle structure and function are assessed using localized GFP and cationic dyes
L-Edge Spectroscopy of Dilute, Radiation-Sensitive Systems Using a Transition-Edge-Sensor Array
We present X-ray absorption spectroscopy and resonant inelastic X-ray
scattering (RIXS) measurements on the iron L-edge of 0.5 mM aqueous
ferricyanide. These measurements demonstrate the ability of high-throughput
transition-edge-sensor (TES) spectrometers to access the rich soft X-ray
(100-2000eV) spectroscopy regime for dilute and radiation-sensitive samples.
Our low-concentration data are in agreement with high-concentration
measurements recorded by conventional grating-based spectrometers. These
results show that soft X-ray RIXS spectroscopy acquired by high-throughput TES
spectrometers can be used to study the local electronic structure of dilute
metal-centered complexes relevant to biology, chemistry and catalysis. In
particular, TES spectrometers have a unique ability to characterize frozen
solutions of radiation- and temperature-sensitive samples.Comment: 19 pages, 4 figure
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