Archaeological field survey is the methodological process by which archaeologists (often Landscape archaeology refers to a body of method and theory for the study of past people and their material culture within the context of their interactions in the wider social and natural environment they inhabited. The landscape may be large, such as a wide marshy river delta or small, like... landscape archaeologists) collect information about the location, distribution and organisation of past human cultures across a large area (e.g. typically in excess of one Ha or ha can mean: Ha, a letter of Cyrillic alphabet Ha, Bhutan Ha, a minor deity in Egyptian mythology Ha, former symbol for element 105, first called hahnium (Ha), later unnilpentium (Unp), now dubnium (Db) hectare (ha), unit of surface area. 1 hectare = 10 000 m² Hausa language (ISO... ha, and quite often in excess of many sq. KM, Km, or km may stand for: Khmer language (ISO 639 alpha-2, km) Kilometre/Kilometer (only km in minuscule is the correct representation of kilometer as an SI unit of length) Kinemantra Meditation Knowledge management, in the field of Library and information science Knowledge Machine, the KM knowledge representation... km). It may be: (a) intrusive or non-intrusive, depending on the needs of the survey team (and the risk of destroying archaeological evidence if intrusive methods are used) and; (b) extensive or intensive depending on the types of research questions being asked of the The Harvesters, by Pieter Brueghel the Elder, 1565: Peace and agriculture in a pre-Romantic ideal landscape, without sublime terrors The term Landscape as most westerners use it, is completely entrenched in western notions of land, nature and art. It is generally only conceived of in terms of an emerging... landscape in question. Surveys can be a practical way to decide whether or not to carry out an Rescue excavation in Southwark, London by the Museum of London Excavation is the best-known and most commonly used technique within the science of archaeology. Individual excavations are normally referred to simply as digs by those who participate, this being an over-literal description of the process. An excavation concerns... excavation (as a way of recording the basic details of a possible site) and may also be ends in themselves, as they produce important information about past human activities in a regional context.

A special type of field survey is the rescue survey, used when a site of possible archaeological importance is under threat. This is usually connected to construction work, and is undertaken to decide whether an excavation is necessary or not before work can commence on the site.

Archaeologists use a variety of tools in survey, including A geographic information system (GIS) is a system for managing data that has a spatial specialized form of an information system. In the strictest sense, it is a computer system capable of assembling, storing, manipulating, and displaying geographically-referenced information, i.e. data identified according to their locations, in a... GIS, Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. For other uses of the acronym GPS, see GPS (disambiguation). The Global Positioning System, usually called GPS (the US military refers to it as NAVSTAR GPS), is a satellite navigation system used for determining one... GPS, In the broadest sense, remote sensing is the measurement or acquisition of information of an object or phenomenon, by a recording device that is not in physical or intimate contact with the object. It is the utilization at a distance (as from aircraft, spacecraft, satellite, or ship) of any device... remote sensing, Geophysical survey is a form of archaeological survey, aimed at confirming an archaeological site and giving guidance to later excavation where surface signs are obscure. It is rarely used to find sites as it is time-consuming and narrow compared to other survey methods (surface survey or aerial survey). It... geophysical survey and aerial photography.

Research and planning

A field survey is usually the result of a long period of research and planning. The process will normally start with the notion that an area is worth further investigation, or that a site requires excavation (or that it should at least be recorded in some way).

Rational

There are several reasons that an area is worth surveying. In no particular order, they are:

• Artifacts found: Locals have picked up artifacts, sometimes found in the local museum but more often in private homes or old buildings such as churches, and it is unclear where they are coming from.
• Literary sources: Old literary sources, in some cases ancient Roman or Greek texts, have provided archaeologists with clues about settlement locations that have not been archaeologically documented. Sometimes the texts may be quite recent; a book on local history that mentions an interesting area.
• Oral sources: In many locations, local stories contain some hint of a greater past, and there is often some truth to them. It is not uncommon for someone to remember that a grandfather who used to walk the hills around a town as a shepherd used to talk about columns from an old temple, without having actually seen these themselves.
• Local knowledge: In many cases, locals actually know where to find something that is of interest to archaeologists. They may not have reported it, either because it's simply a part of their world, or because they fear intrusions on their land.
• Previous surveys: In some places, a survey was carried out in the past, and is recorded in an obscure academic journal. It may have been disregarded at the time, but more recent technologies and finds from other sites might cast a different light on it.
• Previous excavations: Excavations carried out before the middle of the (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999... 20th century are notoriously poorly documented. They were also often carried out in a way that left much of the evidence the modern-day archaeologist is looking for behind, preferring to carry away only fine pottery, jewelry and statues.
• Lack of knowledge: Many areas of the world have little known about the nature and organisation of past human activity at the regional level (even when one or more 'sites' may be known from an area, often little is known about the wider distribution of contemporary settlements, and how settlement patterns may change over time). Archaeological field survey is the primary tool for discovering information about previously uninvestigated areas.

Aerial photography

Main article: Aerial archaeology is the study of archaeological remains by examining them from altitude. The advantages of gaining a good aerial view of the ground had been long appreciated by archaeologists as a high viewpoint permits a better appreciation of fine details and their relationships within the wider site context. Early... Aerial archaeology

Aerial photograhy is a very good tool when planning a survey. Remains of older buildings often show in fields as cropmarks, as they are often just below the topsoil and therefore affect the crops or grass. There should preferably be photographs of the same area at different times of the year, allowing the analyst to find the best time to see cropmarks.

Previous work on the site

If the indicator that started the process was not a record of previous work, the archaeologists will need to check if any work has been done. As many older surveys and excavations were published in papers that were not widely spread, this may be a difficult task. A common way to handle this is through a visit to the area, to check with local museums, historians and older people who might remember something.

Permissions

It is usually a simple matter to gain permission to perform a survey, especially a non-intrusive one. If the area is privately owned, the local laws may or may not require the landowners' co-operation. Permission for an intrusive form of survey may be more difficult to acquire, due to the fear of destroying evidence.

Intrusive vs. non-intrusive surveys

In a non-intrusive survey, nothing is touched, just recorded.

An intrusive survey can mean different things. In some cases, all artifacts of archaeological value are collected. This is often the case if it is a rescue survey, but less common in a regular survey.

Another form of intrusive research is bore holes. Small holes are drilled into the ground, most often with hand-powered bores. The contents are examined to determine the depths at which one might find cultural layers, and where one might expect to strike virgin soil. This can be valuable in determining the cost of an excavation - if there is a build-up of several meters of soil above the layers the archaeologist is interested in, the price will obviously be much higher than if artifacts are found only centimeters below ground.

Extensive vs. intensive survey

Archaeological field survey can be divided into two types: intensive survey and extensive survey. The former is characterised by the complete or near-complete coverage of the survey area at a high-resolution, most often by having teams of survey archaeologists walk in a systematic way (e.g. in Transect is a term for a technique for estimating population densities of animals in an area. It requires an observer to move along a fixed path and to count the individuals along the path and at the same time getting a measure of what distance the individual is to the... transects) over parcels of the landscape in question, documenting archaeological data such as In archaeology, lithic analysis is the analysis of stone tools using basic scientific techniques. Lithic analysis involves measuring various physical aspects of stone tools as well as observing the tool type, its characteristics, the presence features such as cortex, and the like. The term lithic analysis can technically refer to... lithics, The word ceramic is derived from Greek, and in its strictest sense refers to clay in all its forms. However, modern usage of the term broadens the meaning to include all inorganic non_metallic materials. Up until the 1950s or so, the most important of these were the traditional clays, made... ceramics and/or building remains. Extensive survey, on the other hand, is characterised by a low-resolution approach in which (e.g.) only samples of a larger study area (often in excess of several sq KM, Km, or km may stand for: Khmer language (ISO 639 alpha-2, km) Kilometre/Kilometer (only km in minuscule is the correct representation of kilometer as an SI unit of length) Kinemantra Meditation Knowledge management, in the field of Library and information science Knowledge Machine, the KM knowledge representation... km) are visited. Extensive surveys are quite often designed to target the identification of An archaeological site is a place (or group of physical sites) in which evidence of past activity is preserved (either prehistoric or historic), and which has been investigated using the discipline of archaeology. Beyond this, the definition and geographical extent of a site can vary widely, depending on the period... archaeological sites across a large area, whereas intensive surveys are designed to provide a more comprehensive picture of the location of sites and the nature of off-site data (e.g. field systems, isolated finds, etc.). Intensive survey is the more costly, timely, and ultimately informative of the two approaches, although extensive survey can provide important information about previously unknown areas.

Field walk (transects)

An important part of the survey is normally the field walk (or Transect is a term for a technique for estimating population densities of animals in an area. It requires an observer to move along a fixed path and to count the individuals along the path and at the same time getting a measure of what distance the individual is to the... transect). The common way to perform it is to draw a grid, place the survey team on a line and then walk slowly through the area looking for artifacts or other indications. This works best on either plowed ground; as the soil is turned regularly artifacts will move to the top, or on ground that has not been cultivated since the period the archaeologists are interested in.

Modern technology such as Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. For other uses of the acronym GPS, see GPS (disambiguation). The Global Positioning System, usually called GPS (the US military refers to it as NAVSTAR GPS), is a satellite navigation system used for determining one... GPS has made the process much easier, as coordinates can be taken well within the limits necessary for survey work.

In some areas, the field walk is quite different. When searching in dense jungle, buildings may be covered by vegetation, and are therefore virtually invisible even at short distances. The team will then need to look for unnatural changes in the vegeation and landscape to decide if a building is hidden below the vegetation.

Narrowing it down

At this stage, the problem is often that one knows the approximate area, but it needs to be narrowed down. During the field walk, the members of the team are likely to miss minor pieces of artifacts hidden in vegetation. However, if the are all trained to look for the same thing, it is likely that they will miss the same amount of artifacts, and the results of the survey can therefore still be used to draw a map of find frequencies within the grid system. This might in turn make it possible to identify the main site.

Geophysical survey

Main article: Geophysical survey is a form of archaeological survey, aimed at confirming an archaeological site and giving guidance to later excavation where surface signs are obscure. It is rarely used to find sites as it is time-consuming and narrow compared to other survey methods (surface survey or aerial survey). It... Geophysical survey

In recent years, there have been great advances tools for geophysical survey. The most important are resistivity meters and A magnetometer is a scientific instrument used to measure the strength of magnetic fields. Earths magnetism varies from place to place and differences in the Earths magnetic field (the magnetosphere) can be caused by a couple of things: The differing nature of rocks The interaction between charged particles... magnetometer. Both techniques are non-intrusive, and are often used as part of a field survey. While the magnetometer is better for certain locations, the resistivity meter is more often used because of the lower cost.

A resistivity meter passes an electrical current through the ground between two electrodes. A moist soil will offer comparatively low resistance, while drier and denser matter will give a higher resistance reading. In archaeology two, four, or more probes are fitted to a frame, with a waist-high handle for use. The display meter is usually fixed to the handle. Readings are usually taken along pre-surveyed lines at regular intervals, hopefully cutting across any features of interest. This method works best with an flat and well-drained soil with artifacts at a similar depth, natural variations can easily give misleading results. It is best suited to finding strong linear sources like walls or roads by measuring across a suspected placement.

Magnetometers detect variations in magnetic fields, so archaeologists can undertake a magnetic survey. The alignment of naturally occurring magnetic soil particles can be altered by a number of human activities. Simple soil-moving to form ditches or pits can be detected; solid constructions will often contain fewer magnetic material than surround soil; and high heat can realign magnetic particles - indicating the presence of furnaces, kilns or similar.

The difficulty with geophysical surveys is that they do not distinguish between the structures that are of interest to archaeologists and more recent ones.

Analysis

The most important part of the survey is the analysis. The types of questions typically asked of survey data include: what is the evidence for first occupation of an area; when was this area occupied; how are sites distributed; where are sites located; what evidence is there for a settlement hierarchy; what sites are contemporary with each other; how has the modern landscape interfered with the visibility of archaeological remains; what sorts of activities can be recognised (e.g. dwellings, tombs, field systems); how many people lived in this area (at any given time); why did people choose to live in this area; how has the landscape changed over time; what changes in settlement patterns have there been?

At times, one part of the survey may not have yielded the evidence one wanted to find. For instance, very little may have been found during a field walk, but there are strong indications from geophysical survey and local stories that there is a building underneath a field. In such a case, the only way to decide if an excavation is worth the cost is to carefully analyze the evidence to determine which part to trust. On the one hand, the geophyics might just show an old and forgotten waterpipe, but it might also show the wall of just the building the archaeologists were looking for.

The analysis therefore includes careful examination of all the evidence collected. A method often used to determine its value is to compare it to sites of the same period. As the number of well-documented surveys grow, this becomes a slightly easier task, as it sometimes is easier to compare two survey results that a survey result and an excavated site.

External links

The Kythera Island Project (http://www.ucl.ac.uk/kip): Intensive archaeological survey of the Aegean island of Kythera.

Archaeological Survey in Sphakia, Crete (http://sphakia.classics.ox.ac.uk/emccv1988.html)