Electrical resistivity is another type of surveying method; this method uses electricity which is surged through electrodes embedded on the ground surface; subsequently information on the depth and density of the ground is collected by twin ‘potential’ probes which evaluate the ease with which electric current flows through the ground (or how strongly the ground opposes the flow of electric current) and this is displayed in voltage measurements. Furthermore electrical resistivity can also give data on the metallic composition of the ground and whether or not the metal conducts electricity.
Another survey method, shown in the table is the utilization of seismic waves; seismic p-waves can travel through solid and liquid, so information on a possible underwater river or water table can be gathered to possibly help the local residents.
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One last method that is used at times is aerial photography and imagery. Infrared imagery (IR) is employed to identify cool and warm areas, whilst simultaneously shaping a picture, constituting of outlines and features that are not visible from the ground; these images are created from the colour code that is used to specify a certain temperature (e.g. blue for cold).
CONTEXT OF ARCHAEOLOGY:
Archaeology has many environmental implications, for instance archaeology may consequent in the deformation of the landscape, thus causing visual pollution because the landscape loses its beauty and looks unattractive. Another possible environmental factor is that it can cause air pollution as there is a chance that dangerous gases which are overlooked may be released into the atmosphere
Extensive archaeology may incite anger amongst people living in the vicinity of the archaeological site as sounds from machines used in the excavation etc can cause noise pollution.
Historical implications are that archaeological research acts as a ‘gateway’ or ‘portal’ for human beings as it allows us to obtain knowledge on earlier human civilizations and how they used to live. Other knowledge that would be gained is about species of creatures which became extinct, such as dinosaurs, prehistoric mammals and earlier reptiles.
Lastly, archaeology can also affect society. The findings of archeology generally end up in museums – this attracts millions of tourists each year, so more archaeological findings imply more tourists; jobs and businesses can be created out of the increasing tourist levels:
The graph illustrates the annual tourist attractions (in millions). The British museum displays a massive array of rich, historic archaeological findings, such as items belonging to one of Egypt’s greatest pharaohs: Tutankhamen; therefore it entertains the most annual tourists.
BENEFITS AND RISKS OF ARCHAEOLOGICAL METHODS
Resistivity and magnetometry is ideal as its non destructive; this highly beneficial for use in heavily populated areas like cities. It also means an archaeological site can be examined without destroying it in the process. Furthermore, it is exceedingly effective, large areas can be evaluated rapidly. Geophysics (including these techniques) does not require excavation or direct access to subsurface. This means that large areas of earth can be assessed with a far less cost implication than compared to alternative methods, such as drilling/excavation. Although, it is cost effective in comparison to drilling, the costs concerning the equipment that will be used are quite steep (costing a few thousand pounds). 3
In addition, anomalies can occur in magnetometry since magnets are used; there could be highly magnetic igneous rocks or the presence of many iron artefacts (overlapping of iron artefacts may appear to be a large sized artefact) at an historic site. If the site is at an urban setting there will be countless variables that could affect the results like rubbish, iron, and phones- as they could disrupt the signals.
LINK
The geophysical survey method which uses electrical resistivity links with the experiment that I will execute. In the experiment I will calculate the resistivity of a wire – thus, I will endeavor to identify the type of metal it is. The reason why the experiment links in with this archaeological method is because it gives me a taste of what archaeologists do to explore the area of ground.
BIBILIOGRAPHY
- the popular online encyclopedia
BOOK: An introduction to geophysical exploration By Philip Kearey, M. Brooks, Ian Hill
- the popular online
encyclopedia
- an online website giving broad information on many different
methods of archaeological research