How archaeologists study the past. Archaeology is the only branch of human study, which relies more on material human remains than on direct observations on human behaviour or on written evidence. This focus on material evidence makes archaeologists refine the methods and techniques for gathering and analyzing data, which provide maximum extraction of information from available sources (Greene, 77).
Typically, archaeologist divides his time between work in the library, in the field and in the laboratory. He begins with exploring predecessors’ research, and then he is for the field to collect data for his own research. The value of these data often remains unclear until archaeologist returns to the lab and analyses them. The collection of materials is carried out mainly during field works. The important stages here are a discovery of archaeological sites, field survey, excavation, floatation and others.
If fieldwork is the main way to detect archaeological materials, laboratory studies are the primary means of obtaining information necessary for the interpretation of these materials. A significant part of the laboratory work is cleaning finds, their certification and cataloguing. However, only carried out tests allow you to understand their nature and importance. Methods in the truest sense of the word are logical arguments to justify recourse to those or other analytical procedures, whereas techniques are complementary methods of practical operation. Hundreds of methods and techniques are used in archaeological laboratory practice, but archaeologists choose only those that are most suitable for solving problems under the work plan or its subsequent modifications. The important methods on this stage are dating, seriation, reconstruction and others.
Computer technologies are actively used in any modern science. Archaeology is not an exception. The range of computer technologies’ application is extremely wide, ranging from such universal programs like Office packages and financial management systems to highly specialized ones, intended, for example, for the virtual reconstruction of ancient cities (Lock, 44).
Using database management systems (DBMS) and geographical information systems (GIS) in archaeology. The task of structuring the archaeological data with the aim of finding and analyzing information has been existed since the advent of archaeology as a science. At some stage paper files gave way to electronic databases. DBMS enabled to operate with large volumes of information, to search and sort the data on a large number of criteria. This, in turn, led to the creation of databases in different fields: administrative and research registers of monuments, museum catalogues, databases for excavations (findings with attributes, mutual arrangements in layers), the inscriptions, analysis findings, bibliographic and library directories, etc.
The binding of archaeological data to sites stimulates involvement of geoinformation systems (GIS). In fact, GIS is an automated system for spatiotemporal data, the basis of integration of which is provided by geographic information. GIS is a DBMS by its structure, which has geographical reference of data to a specific point on the ground and has integrated spatial analysis. GIS can create archaeological information systems of particular geographic regions, plans of excavation of archaeological sites, and it can explore ancient maps, etc.
GIS provides an opportunity not only to record the spatial location of archaeological findings, but also to predict the location of monuments on still unexplored territories, based on the trends of monuments’ diffusion.
An interesting example of the use of GIS in archaeology is a reconstruction of the landscape change based on ancient maps. To this end maps are scanned, digitized, transferred into a vector format and are superimposed on modern digital maps. After identifying certain objects present on maps the old map binds to the new one. Analysis of combined maps allows you to interpret the landscape change over time. Settlement structure on ancient maps often correlates with the structure of settlements on maps of the early medieval times. This means that you can get a map of the spread of ancient settlements without conducting archaeological excavations (Politis, 32).
Examples include the work of Swedish archaeologists. A unique collection of maps of the XV - XVI centuries, covering large areas of the country has been remained in Sweden. Fig. 1 shows a scanned map of XVIII century with ancient settlements, fields and meadows, and a modern economic map with images of old maps.
Figure 1. Computer analysis of maps of different periods allows you to trace the evolution of landscapes
Expert systems in archaeological studies. A very promising direction of computer applications in archaeology is to use various kinds of expert systems in the analysis of archaeological information. Most of these systems are intended to determine the type of an artefact or material. As an example, let's consider a very interesting project called “Numismatics and computer methods”.
The aim of this project is to create software for the analysis of ancient coins. The main purpose of the programmes is the classification of large quantities of coins to highlight the most interesting exhibits on several criteria (rarity, images of historical figures, etc.). Both archaeologists and experts in the field of computer image recognition techniques took part in the work of the project. The main objective was to identify the coins on the basis of recognition of the elements of the image on the coin.
The principle of work of the system is illustrated in fig. 2 and fig. 3.
Figure 2. Source image of the coins
Figure 3. Appling different filters to identify recognized picture
The first stage of processing is to use conventional filters that let you select a characteristic element of the pattern on the coin. Then algorithms for pattern elements are applied that allows you to allocate separate areas (primitives) that may relate to images of certain objects. Such primitives on the coin may be text, tiara, wheel, horse. Identification is based on the comparison of the image with a known database element primitives.
Computer recognition system is combined with an expert system that analyzes found primitives. For instance, the foregoing example with easily detectable tiara suggests that the coin features a portrait of the king. Therefore, the next step is to recognize the elements of face (eyes, nose, mouth, etc.). The fact that the coin depicts a king, tells the programme that it is probable that the text should recognize the name of the king (at this stage the database of the names of Kings is connected). The system easily reads profile horses and wheels on the other side of the coin. On the basis of these elements expert system reliably concludes that the coin depicts the chariot. Then you can go find the coins from the database that have a similar image of chariots and so on.
Computer-aided design (CAD) systems in archaeology. A customary area of CAD is to develop new products, but with the same success CAD-programs can be used to reconstruct archaeological sites, for example, ancient buildings. Archaeologists have very popular AutoCAD, MicroStation, Easy CAD, AutoCAD Map programmes, and many others. The main way to use such programs by archaeologists is preparing field drawings and three-dimensional reconstruction of the excavation sites, burial structures and settlements, as well as architectural monuments and archaeological finds (see fig. 4).
Figure 4. Computer-aided design as an element of archaeological reconstruction
Until recently most major architectural ensembles of the last were documented in the form of photographs and drawings of orthogonal projections of the surviving structures, and this information had a lot of inconsistencies and errors. Today 3D-reconstruction allows qualitatively changing the picture of documenting the ancient architectural structures.
When you build a 3D model, any discrepancy immediately turns clear. In the case of recreating the architectural ensembles of the past CAD are used to imagine how the structure once existed could look like and to accurately fit all of the items, which survived until our days. Moreover, CAD models can come not only from the geometric constructions, but also of the conditions of strength, stability, etc.
In addition, 3D models can display both the architectural constructions and other archaeological sites, access to which is restricted primarily to avoid their damage or destruction.
Powerful computational abilities of modern computers has led to the emergence of a new scientific discipline — virtual archaeology (Forte, Maurizio, and Alberto Siliotti, 17)
Having a set of 3D models of monuments, you can combine them into a virtual model and place an observer in this virtual archaeological exhibit. Such a model can be interactive, i.e. it allows the observer to navigate in the virtual space, viewing once prevailing architectural ensembles and the whole cities.
With that, all the associated information (archaeological, historical and architectural data, culture information) is available at the click of your mouse. Users will have a unique opportunity to see the architectural ensemble, as it looked in the past and immediately switch to the modern State model of the same architectural complex.
Data about once existing cities were gathered by means of field archaeology for many years. Ancient buildings were usually preserved in the form of ruined walls destroyed by wars, fires, natural disasters. And only with the advent of powerful computers the images of previous times have become be re-built in the former magnificence by means of virtual archaeology. In addition, the introduction of virtual reality technologies has brought archaeology to education and entertainment industries.
A dream of archaeologists to recreate everything that ever was built by our ancestors (Stonehenge, the Coliseum, Pompeii, the Acropolis of Athens) — is gradually becoming realistic. Many projects have already been implemented. Various groups have already done a lot of reconstructions. As a virtual model, one can see the the Flavian Amphitheatre, visit the virtual model of the Basilica of San Francesco in Assisi, see how Çatalhöyük (the oldest city in the world that once existed in South-Central Turkey) looked like.
Virtual reconstruction of Fatehpur Sikri. One of the most striking examples of a virtual reconstruction of the ancient city is a project to recreate the ancient Indian palace complex, Fatehpur Sikri. The project was implemented with the participation of the CAD and Graphics Department of the National Centre for Software Technology (Bombay, India) (Sharma, 38).
The work was carried out in several stages. First, an archaeological material was collected, which gave extensive information: detailed plans of various sections of buildings, photographs, archaeological research, etc. When using orthogonal projection (see fig. 5) it was revealed that most plans are not consistent among themselves, and that the drawings are made in different scales with errors, and the height of many objects is incorrect. All inconsistencies were studied by using field measurements and verified by photos of the terrain; some information was clarified on the basis of historical archives.
Figure 5. Orthogonal plans of Fatehpur Sikri complex
The next step is to choose the appropriate transfer of orthogonal projections into 3D-model. This program was the AutoCAD (see fig. 6), which allowed easily exporting the data in 3D Studio MAX. Wire model was exported in 3D Studio MAX and was optimized, i.e. extra polygons were folded (see fig. 7). An important task of this project was to determine the optimal balance between the power of computers and the details of the model.
Figure 6. Modeling architectural ensemble with AutoCAD
Figure 7. Image of textures fragment (left), built from a wire model (right)
Textures were prepared on the basis of preserved photographs. The data of outside and inside lighting were modelled programmatically. The textures turned out to be the most important and difficult part of the project, because they gave realism to the virtual city. Many patterns were reconstructed manually from the wreckage and were restored and retouched by designers (see fig. 8).
Figure 8. Textures edited and retouched by a designer
The resulting model parameters were quite impressive: around 600 thousand of triangles and about 44 MB of textures.
The results of the work are presented in (see fig. 9).
Figure 9. Various views on Fatehpur Sikri reconstruction
Conclusion. It is worth noting that the list of the aspects of using computers in archaeology is not exhaustive. For example, there is such an interesting direction, as system modelling: scientists are trying to solve archaeological problems by setting certain rules, restrictions, outgoing and incoming resources and to understand how there were such complex processes, such as the colonization of the Americas or the death of Maya civilization. The computerized technology and modern field studies, during which GPS system, electronic microscope, digital camera and other devices are applied, are also commonly used.
Works Cited
Forte, Maurizio, and Alberto Siliotti. Virtual Archaeology: Re-creating Ancient Worlds. New York: H.N. Abrams, 1997. Print.
Greene, Kevin. Archaeology, an Introduction: The History, Principles, and Methods of Modern Archaeology. Philadelphia: U of Pennsylvania, 1995. Print.
Lock, G. R. Using Computers in Archaeology: Towards Virtual Pasts. London: Routledge, 2003. Print.
Politis, Dionysios. E-learning Methodologies and Computer Applications in Archaeology. Hershey: Information Science Reference, 2008. Print.
Sharma, D. V. Archaeology of Fatehpur Sikri: New Discoveries. New Delhi: Aryan International, 2008. Print.