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EAC Guidelines for the use of Geophysics in Archaeology: Questions to Ask and Points to Consider.Schmidt, Armin R., Linford, P., Linford, N., David, A., Gaffney, Christopher F., Sarris, A., Fassbinder, J. January 2015 (has links)
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 ‘best’ 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. “If all you have is
a hammer (or magnetometer), driving a screw becomes
impossible”.
Especially in the American literature the term ‘remote
sensing’ 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 system’s 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.
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Geofyzikální průzkum v areálu středověké tvrze v Popovicích (okr. Benešov) / The geophysical survey in area of the mediaeval fortress in Popovice (township Benešov)Vovsová, Jana January 2014 (has links)
The Master's thesis "Geophysical survey in the area of the mediaeval fortress in Popovice" is divided into two parts. The first part is theoretical and summarizes the possibilities of using electrical resistivity tomography method (ERT) in archaeology. The second part deals with the actual geophysical prospecting in the area of the mediaeval fortress in Popovice (Benešov county). General information on the locality including geological setting, past geophysical exploration in the area, history of the object, archaeological findings and overview of construction development are addressed in this part, prior to the description of the field measurements. Methods used on the site are then specified: symmetrical resistivity profiling, dipole electromagnetic profiling, electrical resistivity tomography and ground penetrating radar. Subsequently, the process of field measuring in the area of the fortress is described and the data processing methods are discussed. The results of these measurements and their interpretation on the basis of compiled geophysical maps and sections are presented finally. Key words: geophysical survey, archaeology, fortress in Popovice (Benešov county).
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Gravity studies over West AntarcticaBurris, Svetlana Gennadiyevna 26 April 2013 (has links)
This thesis describes the results of new analysis of gravity studies over West Antarctica. Set on the Siple Coast, an airborne geophysical survey was flown between 1994 and 1997 that covered the trunk of Bindschadler Ice Stream and the up-stream areas, including Whitmore Accommodation Zone and Byrd Subglacial Basin. The new gravity reduction methodology removed vertical and horizontal accelerations, the Eötvös effect, and the theoretical gravity; unlike previous analyses, this reduction did not level individual lines, preserving the high frequency data and avoiding introduction of new errors. This reduction provided the free-air gravity disturbance over the area, which was then leveled and registered by the more regional extensive GOCE satellite gravity. The processing and reduction of the data improved the high frequency signal over previous work on the data, giving better definition of small scale, short wavelength features, which works well with satellite gravity data that emphasizes the large scale, long wavelength features. The leveled free-air gravity was then processed with a FORTRAN 90 program that calculates the Bouguer disturbance based on the free-air gravity and the topography. The topography was gathered concurrently with the gravity with ice penetrating radar during the airborne survey. The Bouguer disturbances provide a crustal model of the area. The final Bouguer disturbance was also corrected for the ice above sea level, which was calculated with a simple Bouguer slab correction. Finally, a power spectrum analysis was run on a profile in the Bouguer gravity disturbance in order to complete a spectral analysis. The spectral analysis provides crustal density boundaries for a density anomaly near the surface, a mid-crustal anomaly, and the Moho boundary. The improved the high frequency content of the data allows spectral analysis down to 4 km. The differing crustal thickness from spectral analysis also shows the character and extent of the West Antarctic Rift System, the northern flank of which extends out from Marie Byrd Land and into the survey area. Bindschadler Ice Stream is located on the WARS rift floor and MacAyeal Ice Stream sits on the rift flank. / text
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Ohio Hopewell Earthworks: an examination of site use from non-mound space at the Hopewell SitePederson Weinberger, Jennifer 15 March 2006 (has links)
No description available.
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Geophysical survey on a southern French oppidum.Armit, Ian, Horsley, T., Marty, F. January 2008 (has links)
No / No Abstract
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Optimization of Electrical Geophysical Survey Design for Hydrogeological Applications and Subsurface Target DiscriminationGoode, Tomas Charles January 2012 (has links)
Geophysical imaging methods significantly enhance our knowledge of subsurface characteristics and their use has become prevalent over a range of subsurface investigations. These methods facilitate the detection and characterization of both metallic and nonmetallic subsurface targets, and can provide spatially extensive information on subsurface structure and characteristics that is often impractical to obtain using standard drilling and sampling procedures alone. Electrical imaging methods such as electrical resistivity tomography (ERT) have proven to be particularly useful in hydrogeologic and geotechnical investigations because of the strong dependence of the electrical properties of soils to water saturation, soil texture, and solute concentration. Given the available geophysical tools as well as their applications, the selection of the appropriate geophysical survey design is an essential part of every subsurface geophysical investigation. Where investigations are located in an area with subsurface information already available, this information may be used as a guide for the design of a geophysical survey. In some instances, no subsurface information is available and a survey must be designed to cover a range of possible circumstances. Yet, in other instances, there may be significant subsurface information available, but because of subsurface complexities, a geophysical survey must still be designed to cover a broad range of possibilities. Demonstrating the application and limitations of ERT in a specific field application, the first investigation presented in this document provides guidance for developing methods to improve the design and implementation of ERT surveys in a complex subsurface environment. The two investigations that follow present the development of a relatively simple optimization approach based on limited forward modeling of the geophysical response for both static and mobile surveys. This process is demonstrated through examples of selecting a limited number of ERT surveys to identify and discriminate subsurface target tunnels (with a simple cylindrical geometry). These examples provide insights into the practical application of the optimization process for improved ERT survey design for subsurface target detection. Because of their relative simplicity, the optimization procedures developed here may be used to rapidly identify optimal array configurations without the need for computationally expensive inversion techniques.
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Casting Identities in Central Seclusion : Aspects of non-ferrous metalworking and society on Gotland in the Early Medieval PeriodGustafsson, Ny Björn January 2013 (has links)
The aim of this thesis has been to investigate and interpret late Iron Ageand Early Medieval traces of non-ferrous metalworking on the islandGotland, Sweden. Gotland was not, based on the archaeological record, anintegrated part of the common Scandinavian culture. Instead a local,endemic cultural expression had developed; a seclusion which lasted forcenturies despite the islands central position in the Baltic Sea. In thepast, key elements for the understanding of local settlement- and burialpractices as well as the local material culture were mainly recovered andreported by local farmers. A specific category of such finds – so-called‘bronze slag’ is discussed and partly reinterpreted in the first study ofthis thesis. Two further studies treat different aspects of metalworkingand metalworkers – one discusses common archaeological notions ofScandinavian workshops, production sites and metalworkers from a criticalperspective while the other mainly focuses on the Gotlandic finds frommetal-detector surveys carried out over the last 35 years. Based on whereand to which extent, both from a quantitative and a qualitative point ofview, these finds occur a hierarchical classification into four sub groupsis presented – ordinary farm sites with traces of non-ferrous metalworking,workshop sites, potential workshop sites and last, extrovert harboursettlements. A fourth study presents an attempt to evaluate the usefulnessof magnetometry in delimiting extant traces of high-temperature crafts,such as metalworking. The last study of the thesis presents an attempt touse trace elements analysis of skeletal lead in human bone to identifypotential non-ferrous metalworkers. As the wearing of endemic Gotlandic jewellery appears to have been centralin the manifestation of the local identity it is argued that themetalworking artisans played a crucial role in defining how this identitywas signalled and displayed via the jewellery and dress-related metalobjects. It is further suggested that these artisans might have played animportant role in upholding the local economy before the advent of localminting. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Manuscript.</p>
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Geofyzikální průzkum pro využití hlubinné geotermální energie na lokalitě Nová Paka / Geophysical survey for deep geothermal energy exploitation at the site Nova PakaKarousová, Magda January 2010 (has links)
Title: Geophysical survey for deep geothermal energy exploitation at the site Nova Paka Author: Magda Karousová Supervisor: Prof. RNDr. Miloš Karous, DrSc. Supervisor's e-mail address: karous@geonika.com The topic of this thesis is a literature search of geological, geophysical, and geothermal information about wider surroundings of the area of Nova Paka and a complete geophysical survey focused on mapping of deeper fault zones and verification of Permo-Carboniferous sediments thickness. The area has been preliminarily assessed as promising for the use of deep geothermal energy. It belongs to the south-western part of Krkonoše Piedmont Basin. The bedrock of the basin is formed by Proterozoic metamorphites. Heating of surrounding rocks by intrusions of local volcanics during the Younger Tertiary is considered important for geothermal applications. The cover of metamorphic bedrock by sediments may indicate accumulation of the heat from the bedrock at relatively shallow depths of several hundred meters. Geophysical measurements, namely reflection and refraction seismics, gravimetry and resistivity profiling identified two major fault zones of east-west and northwest-southeast direction. The interpretation of the data obtained by geophysical sounding methods, namely seismic reflection and vertical...
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Detecting Remnants of the Past: Archaeo-Geophysical Prospection of Fremont Sites in Southern Utah ValleyJepsen, Jacob P 08 July 2021 (has links)
The variable contexts of Fremont habitation sites in Utah Valley often make identification of those sites very challenging for archaeologists. Pit houses and other structures throughout the valley are frequently in plowed fields or other disturbed contexts that obscure their more exact location and nature. The application of geophysical technologies at archaeological sites throughout the world, including in North America, has proven to be an effective means of subsurface archaeological survey. However, geophysical techniques have been underutilized in Fremont archaeology. This paper reports on the employment of two geophysical methods, ground-penetrating radar (GPR) and fluxgate gradiometer surveys, at three known Fremont habitation sites in southern Utah Valley – the Wolf Village, Wolf Mound, and Snow Farm sites. The preliminary geophysical surveys and later ground-truthing of various geophysical anomalies reveals the effectiveness of these methods in identifying where architectural or other cultural features exist below the surface.
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Searching for Unmarked Graves at Historic Carter Mansion, Elizabethton, TNWhite, Heather, Ernenwein, Eileen G 07 April 2022 (has links)
Carter Mansion is a well-known historic site in Tennessee. It is estimated to have been built in the 1770s and is believed to be the oldest frame house, a house with a wooden skeleton for the base, in the state. This house was built by John and Landon Carter, father, and son respectively, who were well known influential leaders of the Watauga Settlement in the late 18th century. Prior to their arrival, the area was home to Native Americans. The aim of this research was to perform a geophysical survey of a previously unresearched area of the site, providing guidance for future development of the property. A ground penetrating radar (GPR) survey was conducted with a GSSI SIR4000 with 400 MHz antennas. Previous research was able to identify both historic and prehistoric graves in other areas of the property. This project extends this knowledge and aims to determine if there are graves associated with the headstones of the Carters on the eastern margin of the property, thus enriching the history and prehistory of the site without disturbing the grounds.
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