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Dating refers to the archaeological tool to date artefacts and sites, and to properly construct history. Relative techniques can determine the sequence of events but not the precise date of an event, making these methods unreliable. This method includes carbon dating and thermoluminescence. The first method was based on radioactive elements whose property of decay occurs at a constant rate, known as the half-life of the isotope. Today, many different radioactive elements have been used, but the most famous absolute dating method is radiocarbon dating, which uses the isotope 14 C.
Aerial photography can also provide useful information for planning the excavation.
In unobstructed fields, past human occupation of an area is evident through visible soil stains left by plowing, digging, and construction.
Before beginning the actual excavation, an archeologist prepares a topographical map of the site that includes such details as roads, buildings, bodies of water, and various survey points. This activity allows researchers to compare site location with natural land-forms or regional terrain to establish settlement patterns, a theory about where people used to live and why they chose to live there.
Prior to excavating the site, a series of physical gridlines are placed over it to serve as points of reference. In staking out the grid, the archeologist essentially turns the site into a large piece of graph paper that can be used to chart any finds.
The site grid is then mapped onto a sheet of paper. As objects are discovered in the course of the excavation, their locations are recorded on the site map, photographed in place, and catalogued.
Archeology has undergone radical changes since the time when an excavation was simply a mining of artifacts. Today, the removal of artifacts requires that the spatial relationships and context in which they are found be fully documented.
Vertical relationships may yield information about the cultural history of the site, and horizontal relationships, about the way the site was used. Many archaeologists excavate sites in arbitrary levels, small increments of excavation, paying close attention to any changes in soil color or texture to identify various strata. In horizontal excavation, the archeologist may plow strips along the surface of the site to expose any objects lying near the surface.
The excavation of a site proceeds by these methods until, layer by layer, the foundations of the site are uncovered. Often, excavation ends when sterile levels, strata without artifacts, are repeatedly uncovered. Conventional excavation tools include, roughly in order of decreasing sensitivity, a magnifying glass, tape measure, pruning shears, bamboo pick, whiskbroom and dustpan, grapefruit knife, trowel, army shovel, hand pick, standard pick, shovel, and perhaps in some cases, even a bulldozer.
Most of the excavation work is done with a shovel, but whenever fragile artifacts are encountered, the hand trowel becomes the tool of choice. Archeologists record spatial information about a site with the aid of maps.
Measuring tools range from simple tapes and plumb bobs to laser theodolites. The accuracy of a map is the degree to which a recorded measurement reflects the true value; the precision of the map reflects the consistency with which a measurement can be repeated. In the course of an excavation, the archeologist carefully evaluates the sequential order that processes such as the collapse of buildings or the digging of pits contribute to the formation of a site.
In addition, the archeologist typically notes such details as soil color and texture, and the presence and size of any stones. The way the research proceeds at the site will depend on the goal of the excavation.
If the purpose of the excavation is to document the placement of all retrieved artifacts and fragments for the purpose of piecing broken objects back together, the level of recording field data will be much finer than if the goal is simply to retrieve large objects. In cases where the goal of the site research is, for example, to recover flakes and chips of worked stone, digging at the site typically involves a trowel and whisk broom, and almost always, screening or sifting techniques.
One-quarter-inch 6 mm screens are usually fine enough for the recovery of most bones and artifacts, but finer meshes may be used in the recovery of seeds, small bones, and chipping debris. When a screen is used, shovels full of soil are thrown against or on the screen so that the dirt sifts through it, leaving any artifacts behind. Another technique frequently utilized in the recovery of artifacts is water-screening.
Excavations dating methods
By using a water pump to hose down the material to be screened, the process of recovery is sped up and the loss of objects that might be missed or damaged in the course of being dry-screened can be avoided. A drawback in using this recovery technique is that it generates large quantities of mud that may cause environmental damage if dumped into a stream. Elaborate flotation techniques may be used to recover artifacts, seeds, small bones, and the remains of charred plant material.
Excavation methods are the various techniques used within archaeology to dig, uncover, identify, process, and record archaeological remains. Archeological excavation involves the removal of soil, sediment, or rock that covers artifacts or other evidence of human activity. In a sense, excavation is the surgical ct of archaeology: it is surgery of the buried landscape and is carried out with all the skilled craftsmanship that has been built up in the era since archaeological pioneers Heinrich Schliemann, often considered to be the modern discoverer of prehistoric Greece, and Flinders Petrie, who invented a sequence dating method that made possible the reconstruction of history from the remains of ancient cultures. Excavations . Or anomalous information could show up errors in excavation such as "undercutting". Dating methodology in part relies on accurate excavation and in this sense the two activities become interdependent. Digital recording. Archaeological excavation is an unrepeatable process, since the same area of the ground cannot be excavated twice.
In these techniques, debris from the site is placed in a container of pure or chemically treated water. The container is then shaken, causing small objects to float to the surface where they can be recovered. Archeologists have developed elaborate modifications of this technique, some involving multiple trays for the sorting of objects, to facilitate the recovery of artifacts.
Many of these artifacts are analyzed under a microscope to look for clues about manufacture and use. The smallest artifacts, microartifacts such as pollen and seeds, require the use of a microscope for simple identification. Electrical resistivity - A remote sensing technique that determines the character of subsurface sediments or the presence of objects based on variations in the resistance to an electrical current passing through the subsurface. Stratigraphy - The study of layers of rock or soil, based on the assumption that the oldest material will usually be found at the bottom of a sequence.
Archaeologists use many different techniques to determine the age of a particular artifact, site, or part of a site. Two broad categories of dating or chronometric techniques that archaeologists use are called relative and absolute dating.
Theodolite - An optical instrument consisting of a small telescope used to measure angles in surveying, meteorology, and navigation. Topographic map - A map illustrating the elevation or depth of the land surface using lines of equal elevation; also known as a contour map. Prior to being sent to the laboratory for processing, artifacts are placed in a bag that is labeled with a code indicating where and in which stratigraphic layer the artifacts were found.
All relevant information about an artifact is recorded in the field notes for the site. Because excavation permanently destroys at least a portion of a site as a source of archeological data for future generations, it is essential that the results of an excavation be promptly published in a form that is readily accessible.
Current practice is to publish only portions of the complete field report, which is based on analyses of physical, biological, stratigraphic, and chronological data. But many archeologists are of the opinion that the public, which is widely viewed as having collective ownership of all matters relating to the past, has a right to view even unpublished field records and reports about a site.
See also Archaeological mapping ; Artifacts and artifact classification. Fagan, Brian M. Archaeology: A Brief Introduction.
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Guilford, CT: Lyons Press, Russell, Ian, ed. New York : Springer, Wenke, Robert J. New York : Oxford University Press, Cite this article Pick a style below, and copy the text for your bibliography.
April 28, They result from the accumulation of remains caused by centuries of human habitation on one spot. The sites of the ancient cities of Troy and Ur are examples.
(t/f) Carbon dating is a relative dating method used to date rocks and minerals. False (t/f) Although excavations at Olduvai Gorge have yielded abundant archaeological traces, no hominin remains have ever been found there. Mar 17, Dating refers to the archaeological tool to date artefacts and sites, and to properly construct history. All methods can be classified into two basic categories: a) Relative dating methods: Based on a discipline of geology called stratigraphy, rock layers are used to decipher the sequence of historical geological events. Relative techniques can determine the sequence of events but not the precise date of an event, making these methods Author: Johnblack. Apr 02, Archaeological methods are the techniques employed by archaeologists to study past human civilizations. In the 21st century, the different methods of archaeology include high-tech analysis of archaeological sites with magnetic equipment, electrical sensors, and even satellite photography.
Another type consists of closed sites such as pyramids, chambered tombs, barrows burial moundssealed caves, and rock shelters. In other cases there are no surface traces, and the outline of suspected structures is revealed only by aerial or geophysical reconnaissance.
Finally, there are sites in cliffs and gravel beds where many Paleolithic finds have been made. The wide range of techniques employed by the archaeologist vary in their application to different kinds of sites.
The opening of the tomb chamber in an Egyptian pyramid is, for example, a very different operation from the excavation of a tell in Mesopotamia or a barrow grave in western Europe. Some sites are explored provisionally by sampling cuts known as sondages. Large sites are not usually dug out entirely, although a moderate-sized round barrow may be completely moved by excavation. Whatever the site and the extent of the excavation, discovery or location is typically followed by surveying and mapping, site sampling, and the development of an excavation plan.
One element of this technique is common to all digs-namely, the use of the greatest care in the actual surgery; in artifact classification, analysis, and dating; and in the recording of what is found by word, diagram, survey, and photography. To a certain extent all excavation is destruction, and the total excavation of a site subsequently engulfed by a housing estate or by gravel digging is total destruction.
Truly great excavators leave such a fine record of their digs that subsequent archaeologists can re-create and reinterpret what they saw and found. To delay publishing the results of an excavation within a reasonable time is a serious fault from the point of view of archaeological method.
An excavation is not complete until the printed report is available to the world. Often the publication of the report takes as long as, or even much longer than, the actual work in the field.
When a site like the Palace of Minos at Knossos or the city of Harappa in Pakistan has been excavated and the excavations are over, the excavator and the antiquities service of the country concerned have to face the problem of what to do with the excavated structures. Should they be covered in again, or should they be preserved for posterityand if preserved, what degree of conservation and restoration is permissible? This is similar to the issue that arises in connection with the removal of antiquities from their homeland to foreign museums, and there is no simple or generally accepted answer to it.
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Archaeology Dating Lecture Part 2
Thank you for your feedback. Excavation archaeology. See Article History. Read More on This Topic. Excavation is the surgical ct of archaeology: it is surgery of the buried landscape and is carried out with all the. Get exclusive access to content from our First Edition with your subscription. Subscribe today. Learn More in these related Britannica articles:. Excavation is the surgical ct of archaeology: it is surgery of the buried landscape and is carried out with all the skilled craftsmanship that has been built up in the last hundred years since Schliemann and Flinders Petrie.
Excavation s can be classified, from the. More than years separate the first excavations in Mesopotamia-adventurous expeditions involving great personal risks, far from the protection of helpful authorities-from those of the present day with their specialist staffs, modern technical equipment, and objectives wider than the mere search for.
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