Excavation (archaeology)

Under an excavation or excavation is understood in the German-speaking world the archaeological or paleontological excavation of a covert from the ground or from ground or Steinauftragung findings, in which this process is documented with scientific reliability. It is ultimately a controlled destruction of the evidence. The size of the excavation area is based on the finding in itself, the means available and the acute need.

• 2.1 Planagrabung
• 2.2 Stratigraphic excavation
• 2.3 German and English excavation

• 3.1 Preparation of the surface
• 3.2 Findings processing and documentation

Basics

Fund and findings

In the excavation technique ( moving objects, usually artifacts) and findings ( immovable structures, usually soil consistencies, usually a delimited context) distinction between finds.

Doing all visible structures (walls, waste pits, ditches, post holes, layers ) are described findings, where in principle also to be referred to the excavation is not immediately visible structures as findings are ( for example Fund concentrations, patterns of Fund distribution, heavy metal pollution of soil, phosphate content of the soil ). Nothing to find archaeologically relevant counts as a negative finding.

Excavation types

There are the following types of excavations:

• Research excavation: The finding has the highest priority. There are enough time and resources for a comprehensive scientific excavation available.

• Rescue excavation or emergency excavation: The finding has been acutely threatened by imminent construction or already damaged or exposed by erosion and is now documented as possible under great time pressure. The transitions between emergency and rescue excavation route and archeology are often blurred.
• Teaching excavation: The finding is part of a course, excavated in most cases an archaeological University Institute, with students so that they gain an insight into the practical excavation techniques. Subsequently, an excavation work up ( material and report evaluations ) takes place in one or more other courses. In general, participation in a training excavation in the course of studying archaeological subjects required.

The excavation technique has three basic processes:

• The exploratory excavation: This is a small area dug to gain first insights into the floor and finding situations: It is performed as: To sift point excavation, a study in a location to recover about a single Fund or obtained from a measurement feature
• Sondierschnitt or search interface: An interface exposes a local profile by finding a location. General extent of the excavation site and expected Fund layers can be read to him. The best-known is probably the Sondierschnitt Schliemann trench that runs through the hills of Hisarlık ( Troy), then a revolutionary and pioneering approach, today the method is viewed critically

Almost all excavations are based on the stratigraphy of the findings. This is the observable in a vertical layer profile sequence of more or less horizontally extending Straten. The lower limit of an excavation is to achieve the natural, created without human influence soil layers or the grown rock in the ideal case tried in research excavations. In emergency excavations at least the depth to be excavated, which is also reached by the construction project itself.

Be distinguished from scientific excavations are illegal excavations, which left in its focus on special finds in the findings on devastating damage - apart from legal and moral aspects.

Excavation Technology

Principle, be in archeology excavation techniques distinguish two different ( in many variants in the plant of the cuts and the documentation ):

• Excavation for artificial layers (better: according to arbitrary layers) Planagrabung.
• Excavation by natural layers (better: according evident layers) layers excavation or Stratagrabung.

After the horizontal expression is differentiated:

• German excavation ( better surface excavation )
• English excavation ( Wheeler - Kenyon method)

Excavating comprising many more layers at a location are referred to as low- cut. For them, special safety regulations apply as a result of exposure to slipping.

Planagrabung

It is an artificial excavation by (arbitrarily chosen by the excavators ) layers.

When Planagrabung Plana ( Latin planum " level " ) or taps of regular strength are removed, regardless of the course of the individual layers of culture and calibrated on these flat surfaces the findings. The excavation is carried out in horizontal Abträgen arbitrarily fixed strength (eg, 5 cm). The assignment of the finds made ​​via Einzeleinmessung or the Abträgen. The system of profiles is of central importance.

Stratigraphic excavation

It is evident after an excavation (naturally given ) layers

In the stratigraphic excavation or excavation layers each authentic culture layer is exposed minutely. The thickness of the layer is not important, it is at best a working technical problem. This is removed with the recent findings starting findings for detection. There is no direct flat excavation areas, but the assignment of the finds for finding unique.

This excavation technique is based the Harris matrix.

German and English excavation

The German excavation method or surface excavation, the individual results are marked on the ground level and dug it. The German excavation or Wheeler - Kenyon method, however, divides the subgrade into regular squares and is therefore also called the quadrant method. These squares are then excavated and only narrow ridges, so-called control lands to stop, because in them the course of the strata remains verifiable. The advantage of the English Grabungsart the accuracy, disadvantage is the immense amount of work. The term "English excavation " is misleading because today predominantly surface excavations are being carried out in British archeology.

Course of an excavation

Preparation of the surface

After the excavation area is set, the first thing is lifted with the help of an excavator, the plow layer. Retrieved from " plow layer " ( in the true sense of removing the topsoil ) best one can speak in unüberbauten areas. As part of the medieval town center archeology the plow layer may well consist of meter-thick packages of World War rubble.

The thus created rectangular pit, whose initial depth depends on the degree of destruction of the surface top layer, called the excavation trench. Each section now gets a sequential number and is a section leader, usually an experienced fieldworkers or a budding site technician, assumed the lead with its own documentation folder. First, then the edges are by spade just tapped to gain profile and the surface smooth gross pushed himself by shovel to get a first Planum. In fine plaster then the entire area of ​​the section is freed with archaeologists Kellen last remnants of the plow layer.

Then first results can already be seen as they color from that of the surrounding soil on the ground so exposed. Before they are marked, but a network of coordinates is placed over the area first using a total station or theodolite, which is based on the longitude and latitude. Subsequently, the findings can be highlighted and the area to be photographed. After the outline of the cut will be drawn at a scale of 1:100. In this drawing, a part sheet system is entered. The leaves themselves are the part surface at a scale of 1:20, with special findings sometimes even in 1:10 scale dar. order later to be able to understand the differences in height, is leveled the area and entered the Niv - points on the part leaves.

Findings processing and documentation

During the excavation begins the archaeological documentation, which is at the same time even a first form of interpretation, and which will ultimately often only published several years after the excavation. Today, the documentation is usually largely supported by IT.

Example of the sequence of finding processing: The first marked on the exposed subgrade findings initially get consecutive numbers and are located in the part leaves usually at a scale of 1:20. Then, each individual finding is leveled and described as follows: form, alignment, size, location, composition, and putative function. This is the initial contact. If at the end of a finding an additional finding discovered or border several findings together, it is a finding complex which has its own number and initial contact.

Thereafter, the results will be cut in order to obtain a profile. First, a profile string over the finding is curious that divides it into two halves. One half is then removed with a trowel to a new layer. If it is in the new layer to an inserted layer, an intermediate layer which is lined subgrade, leveled again, and then removed down to the underlying. Along the line profile, the profile is perpendicular tapped and photographed. Before now, the profile is drawn at a scale of 1:10, the line profile using the leveling must be stretched horizontally. Thus it can be accurately represented on the drawing of the course of the profile later.

Having done this, the second half of the finding is excavated and the entire findings, the so-called negative Planum photographed. This negative Planum is now again leveled, registered in the part leaves and its composition shown in color. Finally, the overall findings, as in the initial contact again described by the same criteria and found the actual function ( Endansprache ). Also the respective Planum receives a consecutive number, and will be documented in writing, photographs and drawings.

Normal finds ( pottery shards, burnt clay, bone, coal) are bagged, stating the defect code. Special finds, however, such as coins, weapons, etc. are individually calibrated and leveled. Larger findings, such as walls, stoves and the like, photographed, leveled and documented in a scale of 1:10 in a separate drawing.

Thereafter, the entire surface is worn down to the underlying newly created, second Planum, and the sequence begins again. The data thus obtained are presented as excavation report and published.