Encyclopedia  |   World Factbook  |   World Flags  |   Reference Tables  |   List of Lists     
   Academic Disciplines  |   Historical Timeline  |   Themed Timelines  |   Biographies  |   How-Tos     
Sponsor by The Tattoo Collection
Archaeology
Main Page | See live article | Alphabetical index

Archaeology

Archaeology (or archeology) is the scientific study of human cultures through the recovery, documentation and analysis of material remains, including architecture, artifacts, biofacts, human remains, and landscapes. The goal of archaeology is to shed light on human history. Other subfields of anthropology supplement the findings of archaeology, especially cultural anthropology (which studies behavioral, symbolic, as well as material dimensions of culture) and physical anthropology (which includes the study of human evolution and osteology). Other disciplines also supplement archeology, such as paleontology (the study of prehistoric life), including paleozoology and paleobotany, geography, geology, history, art history, and classics.

Archaeology has been described as a craft that enlists the sciences to illuminate the humanities.

Archaeology is an approach to understanding lost cultures and the mute aspects of human history, without a cutoff date: in England, archaeologists have uncovered the long-lost layouts of medieval villages abandoned after the Black Death in the 14th century and the equally lost layouts of 17th century parterre gardens swept away by a change in fashion. In downtown New York archaeologists have exhumed the 18th century remains of the Black burial ground.

In the study of relatively recent cultures which have been observed and studied by Western scholars, archaeology is closely allied with ethnography. This is the case in large parts of North America, the South Pacific, Siberia, and other places. In the study of cultures that were literate or had literate neighbors, history and archaeology supplement one another for broader understanding of the complete cultural context, as at Hadrian's Wall.

Table of contents
1 Importance and applicability
2 Goals
3 History of archaeology
4 Relations with the public
5 Field methods
6 Archaeological laboratory techniques
7 Related topics
8 External links
9 Further reading

Importance and applicability

Most of human history is not described by any written records. Writing did not exist anywhere in the world until about 5000 years ago, and only spread among a relatively small number of technologically advanced civilizations. These civilizations are, not coincidentally, the best-known; they have been open to the inquiry of historians for centuries, while archaeology has arisen only recently. Even within a civilization that is literate at some levels, many important human practices are not officially recorded. Any knowledge of the formative early years of human civilization - the development of agriculture, cult practices of folk religion, the rise of the first cities - must come from archaeology.

Even where written records do exist, they are invariably incomplete or biased to some extent. In many societies, literacy was restricted to the elite classes, such as the clergy or the bureaucracy of court or temple. The literacy even of an aristocracy has sometimes been restricted to deeds and contracts. The interests and world-view of elites are often quite different from the lives and interests of the masses. Any writings that were produced by people more representative of the general population were unlikely to find their way into libraries and be preserved there for posterity. Thus, written records tend to reflect the biases of the literate classes, and cannot be trusted as a sole source. The material record is nearer to a fair representation of society, though it is subject to its own inaccuracies, such as sampling bias and differential preservation.

In addition to their scientific importance, archaeological remains sometimes have political significance to descendants of the people who produced them, monetary value to collectors, or simply strong aesthetic appeal. Many people identify archaeology with the recovery of such religious, political or economic treasures rather than the reconstruction of past societies.

This view is often espoused in works of popular fiction, such as Raiders of the Lost Ark, The Mummy, and King Solomon's Mines where the field has become profitable fodder for entertainment. When such unrealistic subjects are treated more seriously, accusations of pseudoscience are invariably levelled at their proponents. Examples of discredited pseudoarchaeologists include Erich von Däniken and Graham Hancock.

Pseudoarchaeology is indeed an accurate description of much of the amateur archaeology conducted in the 19th century, but the field has changed much since then. These endeavors, real and fictional, are not representative of the modern state of archaeology.

Goals

There is still a tremendous emphasis in the practice of archaeology on field techniques and methodologies. These include the tasks of surveying areas in order to find new sites, and digging sites in order to unearth the cultural remains therein, and classification and preservation techniques in order to analyze and keep these remains. Every phase of this process can be a source of information.

The goals of archaeology are not always the same. There are at least three broad, distinct theories of exactly what archaeological research should do. (These are beyond the scope of the present discussion, and are discussed at length below.) Nevertheless, there is much common ground.

Academic sub-disciplines

Archaeological research is sometimes categorized according to the time period which it studies. Certain civilizations have attracted so much attention that their study has been specifically named. These subdisciplines include Assyriology (the ancient Near East), Classical archaeology (Greece and Rome), and Egyptology (Egypt). In the United States, all branches concerned with civilizations that left behind written records are called historical archaeology.

Prehistoric archaeology concerns itself with societies that did not have writing systems. The term is generally valid only in Europe and Asia where literate societies emerged without colonial influence. In areas where literacy arrived relatively late, it more convenient to use other terms to divide up the archaeological record. In areas of semi-literacy the term protohistoric archaeology can be adopted to cover the study of societies with very limited written records. One example of a protohistoric site is Fort Ross on the northern California coast, which included settlements of literate Russians and non-literate American Indians and Alaska nativess.

Ethnoarchaeology is the study of modern societies resembling extinct ones of archaeological interest, for archaeological purposes. It is often difficult to infer solid conclusions about the structure and values of ancient societies from their material remains, not only because objects are mute and say little about those who crafted and used them, but also because not all objects survive to be uncovered by scholars of a later age. Ethnoarchaeology seeks to determine, for instance, what kinds of objects used in a living settlement are deposited in middens or other places where they may be preserved, and how likely an object is to be discarded near to the place where it was used.

Taphonomy is the study of how objects decay and degrade over time. This information is critical to interpretation of artifacts and other objects, so that the work of ancient people can be differentiated from the later work of living creatures and elemental forces.

A selective list of subdisciplines distinguished by time period or region of study is given below.

The following is a list of other subdisciplines. Some of these are not areas of study in their own right, and are only methods to be used in larger projects.

Cultural resources management

Cultural resources management (CRM) (also called heritage management in Britain) is a branch of archaeology that accounts for most research done in the United States and much of that in western Europe as well. In the United States, CRM archaeology has been a growing concern since the passage of the National Historic Preservation Act of 1966 and most of the archaeology done in that country today proceeds from either direct or related requirements of that measure. In the United States, the vast majority of taxpayers, scholars, and politicians believe that CRM has helped to preserve much of that nation's history and prehistory that would have otherwise been lost in the expansion of cities, dams, and highways. Along with other statutes, this mandates that no construction project on public land or involving public funds may damage an unstudied archaeological site.

The application of CRM in the United Kingdom is not limited to government-funded projects. Since 1990 PPG 16 has required planners to consider archaeology as a material consideration in determining applications for new development. As a result, numerous archaeological organisations undertake mitigation work in advance of (or during) construction work in archaeologically sensitive areas, at the developer's expense.

Among the goals of CRM are the identification, preservation, and maintenance of cultural sites on public and private lands, and the removal of culturally valuable materials from areas where they would otherwise be destroyed by human activity, such as proposed construction. This study involves at least a cursory examination to determine whether or not any significant archaeological sites are present in the area affected by the proposed construction. If these do exist, time and money must be allotted for their excavation. If initial survey and/or test excavation indicates the presence of an extraordinarily valuable site, the construction may be prohibited entirely. CRM is a thriving entity, especially in the United States and Europe where archaeologists from private companies and all levels of government engage in the practice of their discipline.

Cultural resources management has doubtless mitigated the destruction of the archaeological record by the ever-sprawling works of Western civilization, but it leaves something to be desired. CRM is conducted by private companies that bid for projects by submitting proposals outlining the work to be done and an expected budget. It is not unheard-of for the agency responsible for the construction to simply choose the proposal that asks for the least funding. CRM archaeologists face considerable time pressure, often being forced to complete their work in a fraction of the time that might be allotted for a purely scholarly endeavor.

History of archaeology

Origins

The exact origins of archaeology as a discipline are uncertain. Excavations of ancient monuments and the collection of antiquities have been taking place for thousands of years. It was only in the 19th century, however, that the systematic study of the past through its physical remains began to be carried out in a manner recognisable to modern students of archaeology. Prior to this, excavation had tended to be haphazard; the importance of concepts such as stratification and context was completely overlooked. In 1803, there was widespread criticism of Thomas Bruce, 7th Earl of Elgin for removing the "Elgin Marbles" from their rightful place on the Parthenon in Athens; but the marble sculptures themselves were valued by his critics only for their aesthetic qualities, not for the information they might supply about Greek civilisation.

Britain was one of the first countries to develop a systematic approach to archaeology and to recognise it as a discipline in its own right (though the debate over whether it is an "art" or a "science" continues). The first individuals to take a serious interest in the subject were clergymen. Many vicars recorded local landmarks within their parishes, and these might include details of the landscape, as well as ancient monuments such as standing stones -- even where they did not recognise the significance of what they were seeing. It is thanks to them that we know about many archaeological features which have since disappeared or been moved. In the sixteenth and seventeenth centuries antiquarians such as John Leland, John Aubrey and William Stukeley conducted surveys of the country, drawing, describing and interpreting the monuments they encountered.

In America, Thomas Jefferson, possibly inspired by his experiences in Europe, supervised the systematic excavation of an Indian burial mound on his land in Virginia in 1784. Although Jefferson's investigative methods were ahead of his time (and have earned him the nickname from some of the "father of archaeology"), they were primitive by today's standards. He did not simply dig down into the mound in the hope of "finding something"; he cut a wedge out of it in order to examine the stratigraphy. The results did not inspire his contemporaries to do likewise, and they generally continued to hack away indiscriminately at tell sites in the Middle East, barrows in Europe and mounds in North America, destroying valuable archaeological material in the process.

A little later, Napoleon's army carried out excavations during its Egyptian campaign. The emperor had taken with him a force of five hundred civilian scientists, specialists in fields such as biology, chemistry and languages, in order to carry out a full study of the ancient civilisation. The work of Jean-François Champollion in deciphering the Rosetta stone to discover the hidden meaning of hieroglyphics proved the key to the study of Egyptology.

A major figure in the development of archaeological method was the Victorian Augustus Pitt Rivers. Archaeology was still an amateur pastime, but Britain's colonial period had provided the opportunity to study antiquities in many other countries. Pitt-Rivers himself, having caught the bug during his military career, brought many artefacts back from overseas and, having inherited a large estate with numerous prehistoric features, collected more artefacts off his own land. From his personal collection (the nucleus of the museum named after him, in Oxford), he developed a typology, something few had thought of doing but which would be of enormous significance for dating purposes.

William Flinders Petrie is another man who may legitimately be called the Father of Archaeology, His work in Egypt developed the concept of seriation which permitted accurate dating long before scientific methods were available to corroborate his chronologies. He was also a meticulous excavator and scrupulous record keeper and laid down many of the ideas behind modern archaeological recording.

Development of archaeological method

The next major figure in the development of archaeology in the UK was Mortimer Wheeler, whose highly disciplined approach to excavation and systematic coverage of much of the country in the 1920s and 1930s brought the science on swiftly. It was not until the introduction of modern technology, from the 1950s onwards that a similar leap forward would be made in field archaeology. Wheeler's method of excavation, laying out the site on a grid pattern, though gradually abandoned in favour of the open-area method, still forms the basis of excavation technique.

Meanwhile, the work of Sir Arthur Evans at Knossos in Crete had shed light on the Minoan civilisation. Many of the finds from this site were catalogued and brought to the Ashmolean Museum in Oxford, where they could be studied by classicists, whilst an attempt was made to reconstruct much of the original site. Although this was done in a manner that would be considered inappropriate today, it helped raise the profile of archaeology considerably.

The bomb damage and subsequent rebuilding caused by the Second World War gave archaeologists the opportunity to meaningfully examine inhabited cities for the first time. Bomb damaged sites provided windows onto the development of European cities whose pasts had been buried beneath working buildings. Urban archaeology necessitated a new approach as centuries of human occupation had created deep layers of stratigraphy which could often only be seen through the keyholes of individual building plots. In Britain post-war archaeologists such as W. F. Grimes and Martin Biddle took the initiative in studying this previously unexamined area and developed the archaeological methods now employed in much CRM and Rescue archaeology.

Archaeology was increasingly becoming a professional activity. Although the bulk of an excavation's workforce would still consist of volunteers, it would normally be led by a professional. It was now possible to study archaeology as a subject in universities and even schools, and by the end of the 20th century nearly all professional archaeologists, at least in developed countries, were graduates.

Introduction of technology

Undoubtedly the major technological development in 20th century archaeology was the introduction of radiocarbon dating, based on a theory first developed by American scientist Willard Libby in 1949. Despite its many limitations (compared to later methods it is inaccurate; it can only be used on organic matter; it is reliant on a dataset to corroborate it; and it only works with remains from the last 10,000 years), the technique brought about a revolution in archaeological understanding. For the first time, it was possible to put reasonably accurate dates on discoveries such as bones. This in some cases led to a complete reassessment of the significance of past finds. Classic cases included the Red Lady of Paviland. It was not until 1989 that the Catholic church allowed the technique to be used on the Turin Shroud, indicating that the linen fibres were of medieval origin.

Lead, strontium and oxygen isotope analysis can also be applied to human remains to estimate the diet and the even birthplace of study subjects.

Radiocarbon dating was developed almost in tandem with dendrochronology, another valuable archaeological technique. In the western United States dates could be calibrated by reference to the bristlecone pine of California, which can live for four thousand years or more. Elsewhere, tree ring chronologies are created by aligning shorter sequences that overlap in time.

Inorganic items can now also be dated using a variety of techniques adopted from physics and chemistry. Thermoluminescence dating can provide information on the age of ceramics and potassium-argon dating can provide dates for fossilised hominid remains.

Other developments, often spin-offs from wartime technology, led to other scientific advances. For field archaeologists, the most significant of these was the introduction of the geophysical survey, enabling an advance picture to be built up of what lies beneath the soil, before excavation even commences. The entire Roman city of Viroconium, modern day Wroxeter, has been surveyed by these methods, though only a small portion has actually been excavated.

The development of archaeological theory

There is no single theory of archaeology, and even definitions are disputed. Until the mid-20th century and the introduction of technology, there was a general consensus that archaeology was closely related to both history and anthropology. Since then, elements of other disciplines such as physics, chemistry, biology, metallurgy, engineering, medicine, etc, have found an overlap, resulting in a need to revisit the fundamental ideas behind archaeology.

The first major phase in the history of archaeological theory is commonly referred to as cultural, or culture history. The product of cultural history was to group sites into distinct "cultures", to determine the geographic spread and timespan of these cultures, and to reconstruct the interactions and flow of ideas between them. Cultural history, as the name suggests, was closely allied with the science of history. Cultural historians employed the normative model of culture, the principle that each culture is a set of norms governing human behavior. Thus, cultures can be distinguished by patterns of craftsmanship; for instance, if one excavated sherd of pottery is decorated with a triangular pattern, and another sherd with a checkered pattern, they likely belong to different cultures. Such an approach naturally leads to a view of the past as a collection of different populations, classified by their differences and by their influences on each other. Changes in behaviour could be explained by diffusion whereby new ideas moved, through social and economic ties, from one culture to another.

The Australian archaeologist Vere Gordon Childe was one of the first to explore and expand this concept of the relationships between cultures especially in the context of prehistoric Europe. By the 1920s sufficient archaeological material had been excavated and studied to suggest that diffusionism was not the only mechanism through which change occurred. Influenced by the political upheaval of the inter-war period Childe then argued that revolutions had wrought major changes in past societies. He conjectured a Neolithic Revolution which inspired people to settle and farm rather than hunt nomadically. This would have led to considerable changes in social organisation which Childe argued led to a second Urban Revolution which created the first cities. Such macro-scale thinking was in itself revolutionary and Childe's ideas are still widely admired and respected.

In the 1960s, a number of young, primarily American archaeologists, such as Lewis Binford, rebelled against the paradigms of cultural history. They proposed a "New Archaeology", which would be more "scientific" and "anthropological". They came to see culture as a set of behavioral processes and traditions. (In time, this view gave rise to the term processual archaeology). Processualists borrowed from the exact sciences the idea of hypothesis testing and the scientific method. They believed that an archaeologist should develop one or more hypotheses about a culture under study, and conduct excavations with the intention of testing these hypotheses against fresh evidence. They had also become frustrated with the older generation's teachings through which cultures had taken precedence over the people being studied themselves. It was becoming clear, largely through the evidence of anthropology, that ethnic groups and their development were not always entirely congruent with the cultures in the archaeological record.

In the 1980s, a new movement arose led by the British archaeologists Michael Shanks, Christopher Tilley and Ian Hodder. It questioned processualism's appeals to science and impartiality by claiming that every archaeologist is in fact biased by his or her personal experience and background, and thus truly scientific archaeological work is difficult or impossible. This is especially true in archaeology where experiments (excavations) cannot possibly be repeatable by others as the scientific method dictates. Exponents of this relativistic method, called post-processual archaeology, analyzed not only the material remains they excavated, but also themselves, their attitudes and opinions. The different approaches to archaeological evidence which every person brings to his or her interpretation result in different constructs of the past for each individual. The benefit of this approach has been recognised in such fields as visitor interpretation, cultural resource management and ethics in archaeology as well as fieldwork. It has also been seen to have parallels with culture history.

Post-processualism provided an umbrella for all those who decried the processual model of culture, which many feminist and neo-Marxist archaeologists for example believed treated people as mindless automatons and ignored their individuality.

This divergence of archaeological theory has not progressed identically in all parts of the world where archaeology is conducted. Australian archaeologists have embraced post-processualism, while those in the United States freely combine it with older approaches and methods.

Ideology

Much of the early history of professional archaeology was motivated by an attempt to distance itself from pseudo-archeologists and dilettantes, and to establish itself as a science. While this battle has been won, archaeology has been and remains a cultural, gender and political battlefield. Many groups have tried to use archaeology to prove some current cultural or political point. Marxist or Marxist-influenced archaeologists in the USSR and the UK (among others) often try to prove the truth of dialectical materialism or to highlight the past (and present) role of conflict between interest groups (e.g. male vs. female, elders vs. juniors, workers vs. owners) in generating social change. Some contemporary cultural groups have tried, with varying degrees of success, to use archaeology to prove their historic right to ownership of an area of land. Many schools of archaeology have been patriarchal, assuming that in prehistory men produced most of the food by hunting, and women produced little nutrition by gathering; more recent studies have exposed the inadequacy of many of these theories. Some used the "Great Ages" theory implicit in the three-age system to argue continuous upwards progress by Western civilization. Much contemporary archaeology is influenced by neo-Darwinian evolutionary thought, phenomenology, post-modernism, agency theory, and cognitive science.

Schools of theoretical archaeology

These include:

Relations with the public

Early archaeology was largely an attempt to uncover spectacular artefacts and features, or to explore vast and mysterious abandoned cities. Such pursuits continue to fascinate the public, portrayed in books (such as King Solomon's Mines) and films (viz. The Mummy, Raiders of the Lost Ark).

Much thorough and productive research has indeed been conducted in dramatic locales such as Copán; and the Valley of the Kings, but the stuff of modern archaeology is not so reliably sensational. In addition, archaeological adventure stories tend to ignore the painstaking work involved in modern survey, excavation and data processing techniques. Some archaeologists refer to such portrayals as 'pseudoarchaeology'.

Nevertheless, archaeology has profited from its portrayal in the mainstream media. Many practitioners point to the childhood excitement of Indiana Jones films and Tomb Raider games as the inspiration for them to enter the field. Archaeologists are also very much reliant on public support, the question of exactly who they are doing their work for is often discussed. Without a strong public interest in the subject, often sparked by significant finds and celebrity archaeologists, it would be a great deal harder for archaeologists to gain the political and financial support they require.

Where possible, archaeologists now make more provision for public involvement and outreach in larger projects than they once did. However, the move towards professionalisation has meant that volunteer places are now relegated to unskilled labor, and even this is less freely available than before. Developer-funded excavation necessitates a well-trained staff that can work quickly and accurately, observing the necessary Health and Safety and indemnity insurance issues involved in working on a modern building site to tight deadlines. Certain charities and local government bodies sometimes offer places on research projects either as part of academic work or as a defined community project. There is also a flourishing industry selling places on commercial training excavations and archaeological holiday tours.

Archaeologists prize local knowledge and often liaise with local historical and archaeological societies. Anyone looking to get involved in the field without having to pay for the privilege should contact a local group.

Pseudoarchaeology

Pseudoarchaeology is an umbrella term for all activities that claim to be archaeological but in fact violate commonly accepted archaeological practices. It includes much fictional archaeological work (discussed above), as well as some actual activity. Many nonfiction authors have ignored the scientific methods of processual archaeology. (Postprocessualism is a valid branch of archaeology that looks skeptically on claims to scientific impartiality, but it does not conclude that these methods should be entirely dispensed with and forgotten. "Pseudoarchaeology" does not address the issues raised by postprocessualists.)

An example of this type is the author, Erich von Däniken. His Chariots of the Gods (1968), together with many subsequent, lesser-known works, expounds a theory of ancient contacts between human civilization on Earth and more technologically advanced extraterrestrial civilizations. (This theory, known as palaeocontact theory, is not exclusively Däniken's.) Works of this nature are usually marked by the renunciation of well-established theories on the basis of limited evidence, and the interpretation of evidence with a preconceived theory in mind.

Michael Cremo's work would also be regarded by many as pseudoarchaeology.

Looting

Looting of buried treasure is an ancient problem; for instance, many of the tombs of the Egyptian pharaohs were looted in antiquity. The advent of archaeology has made ancient sites objects of great scientific interest, but it has also attracted public attention to the works of past peoples. A brisk commercial demand for artifacts has accelerated the pace of looting and the antiquities trade.

The popular consciousness may associate looting with Third World countries, former homes to some of the less well-known ancient civilizations and lacking the financial resources to protect even the most fabulous sites. In fact, looting has left a significant mark in places as "civilized" and seemingly uninteresting as the United States. Abandoned towns of the ancient Sinagua people of Arizona, clearly visible in the desert landscape, have been destroyed in large numbers. Sites in more densely populated areas farther east have also been looted.

Public outreach

Motivated by a desire to halt looting, to curb pseudoarchaeology, and to secure greater public funding for their research, archaeologists are mounting public-outreach campaigns. They seek to stop looting by informing prospective artifact collectors of the provenance of these goods, and by alerting people who live near archaeological sites of the threat of looting and the danger that it poses to science. Common methods of public outreach include press releases and the encouragement of school field trips to sites under excavation.

Descendant peoples

In the United States, American Indians tend to mistrust archaeology. This mistrust is well-founded. For years, American archaeologists have been digging up Indian burial grounds and other places considered sacred, and carting away any artifacts and human remains to storage facilities for further study. Adding insult to injury, many skeletons were not even thoroughly studied. Furthermore, Western archaeologists' views of the past are different from those of tribal peoples. The West views time as linear; for natives, it is cyclic. From a Western perspective, the past is long-gone; from a native perspective, disturbing the past can have dire consequences in the present. To an archaeologist, the past is long-gone and must be reconstructed; to a native, it is yet alive.

As a consequence of this misunderstanding, American Indians have often attempted to prevent archaeological excavation of sites inhabited by their ancestors, while American archaeologists have paid them little heed. This situation is beginning to change. The Native American Graves Protection and Repatriation Act (NAGPRA, 1990), limits the right of research institutions to possess human remains. Due in part to the spirit of postprocessualism, some archaeologists have begun to actively enlist the assistance of native peoples likely to be descended from those under study.

Archaeologists have also been obliged to re-examine what constitutes an archaeological site in view of what native peoples believe to constitute sacred space. To many native peoples, natural features such as lakes, mountains or even individual trees have cultural significance. Australian archaeologists especially have explored this issue and attempted to survey these sites in order to give them some protection them from being developed. Such work requires close links and trust between archaeologists and the people they are trying to help and at the same time study.

While this cooperation presents a new set of challenges and hurdles to fieldwork, it has benefits for all parties involved. Tribal elders cooperating with archaeologists can prevent the excavation of areas of sites that they consider sacred, while the archaeologists gain the elders' aid in interpreting their finds. There have also been active efforts to recruit aboriginal peoples directly into the archaeological profession.

Field methods

Survey

A modern archaeological project often begins with survey. Regional survey is the attempt to systematically locate previously unknown sites in a region. Site survey is the attempt to systematically locate features of interest, such as houses and middens, within a site. Each of these two goals may be accomplished with largely the same methods.

Survey was not widely practiced in the early days of archaeology. Cultural historians and prior researchers were usually content with discovering the locations of monumental sites from the local populace, and excavating only the plainly visible features there. Gordon Willey pioneered the technique of regional settlement pattern survey in 1949 in the Viru Valley of coastal Peru, and survey of all levels became prominent with the rise of processual archaeology some years later.

Survey work has many benefits if performed as a preliminary exercise to, or even in place of, excavation. It is requires relatively little time and expense, because it does not require processing large volumes of soil to search out artifacts. (Nevertheless, surveying a large region or site can be expensive, so archaeologists often employ sampling methods.) It avoids ethical issues (of particular concern to descendant peoples) associated with destroying a site through excavation. It is the only way to gather some forms of information, such as settlement patterns and settlement structure. Survey data are commonly assembled into maps, which may show surface features and/or artifact distribution.

The simplest survey technique is surface survey. It involves combing an area, usually on foot but sometimes with the use of mechanized transport, to search for features or artifacts visible on the surface. Surface survey cannot detect sites or features that are completely buried under earth, or overgrown with vegetation. Surface survey may also include mini-excavation techniques such as augers, corers, and shovel test pits.

Aerial survey is conducted using cameras attached to airplanes, balloons or even kites. A bird's-eye view is useful for quick mapping of large or complex sites. Aerial imaging can also detect many things not visible from the surface. Plants growing above a stone structure, such as a wall, will develop more slowly, while those above other types of features (such as middens) may develop more rapidly. Photographs of ripening grain, which changes color rapidly at maturation, have revealed buried structures with great precision. Aerial survey also employs infrared, ground-penetrating radar wavelengths, and thermography.

Geophysical survey is the most effective way to see beneath the ground. Magnetometers detect minute deviations in the planetary magnetic field caused by iron artifacts, kilns, some types of stone structures, and even ditches and middens. Devices that measure the electrical resistivity of the soil are also widely used. Most soils are moist below the surface, this gives them a relatively low resistivity. Features such as hard-packed floors or concentrations of stone have a higher resistivity.

Regional survey in maritime archaeology uses side-scan sonar.

Excavation

Archaeological excavation existed when the field was still the domain of amateurs, and it remains the source of the majority of data recovered in most field projects. It can reveal several types of information usually not accessible to survey, such as stratigraphy, three-dimensional structure, and verifiably primary context.

Modern excavation techniques require that the precise locations of objects and features, known as their provenance or provenience, be recorded. This always involves determining their horizontal locations, and sometimes vertical position as well. Similarly their association, or relationship with nearby objects and features, needs to be recorded for later analysis. This allows the archaeologist to deduce what artifacts and features were likely used together and which may be from different phases of activity. For example, excavation of a site reveals its stratigraphy; if a site was occupied by a succession of distinct cultures, artifacts from more recent cultures will lie above those from more ancient cultures.

Excavation is the most expensive phase of archaeological research. Also, as a destructive process, it carries ethical concerns. As a result, very few sites are excavated in their entirety. Sampling is even more important in excavation than in survey. It is common for large mechanical equipment, such as backhoes (JCBs), to be used in excavation, especially to remove the topsoil (overburden), though this method is increasingly used with great caution. Following this it is usual to hand-clean the exposed area with trowels or hoes to ensure that all features are apparent.

The next task is to produce a site plan and then use it to help decide the method of excavation. Features dug into the natural subsoil are normally excavated in portions in order to produce a visible archaeological section for recording. Scaled plans and sections of individual features are all drawn on site, black and white and colour photographs of them are taken and recording sheets are filled in describing the context of each. All this information serves as a permanent record of the now-destroyed archaeology and is used in describing and interpreting the site.

Archaeological laboratory techniques

Related topics

External links

Further reading