CIPA 2003 XIX th International Symposium, 30 September - 04 October, 2003, Antalya, Turkey 
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from aerial photographs, the standard method for medium scale 
map production, often focuses the problem that the physical 
earth surface is not visible because it is covered by vegetation. 
That is why digital elevation models sometimes reflect the 
vegetation surface instead of the physical ground surface. 
Having all these shortcuts, either proved or suspected, in mind 
the coincidence of the different TIN’s within a 1 to 2 metres 
range on average is very well in coincidence with the quality of 
the available data sets. 
Figure 5. Spatial distribution of height difference 
TIN 1/500-TIN 1/5000 
Figure 6 shows an overlay of contour lines in the area around 
the two major hillocks Biiyukkale and Kuciikkale in a zoomed 
view. The smooth dashed lines are generated from the paper 
map TIN, the more jittery solid lines are the result of the highly 
detailed TIN generated from ground survey. 
Figure 6. Overlay of contour lines generated from 1/5000 scale 
TIN (dashed lines) and from 1/500 scale TIN (solid lines). 
Digital terrain models can also be used to generate cross 
sections. Figure 7 shows the presentation of such a cross 
section, again from both digital elevation models. As can be 
seen the top of the local elevation appears to be cut in the paper 
map DEM, but otherwise both curves fit well. 
Figure 7. Overlay of cross sections generated from 1/5000 scale 
TIN (solid line) and from 1/500 scale TIN (dashed line) 
4.4 Applications in Archaeological Field Research 
As an extract of the wide range of DEM applications, this 
section describes some examples of how digital elevation 
models can support archaeological research activities. 
4.4.1 Volume Calculations: The historical theatre which 
was discovered in the research area is one of the most important 
archaeological remains which are currently known in the 
Tavium archaeological site. The volume of the earth mass 
which had to be moved during the excavation of the theatre 
could be easily calculated from the DEM. All points actually 
located in the theatre area were removed from the DEM. 
Another DEM was calculated from the reduced data set. In that 
way, the present surface of the theatre area was replaced by 
another surface which was calculated from the surrounding 
points located in the slope surface (see Figure 7). 
Figure 7. Detailed TIN of terrain surface in the theatre area: 
current terrain surface with cavity (left), 
simulated surface without cavity (right) 
By performing a so-called cut fill operation between both 
DEM’s, namely the DEM not containing and the DEM 
containing the theatre cavity, the earth volume which had to be 
removed to construct the theatre was estimated to be about 
2.000 cubic metres. 
4.4.2 Visibility Analysis: This is another DEM application 
which can support the archaeological research in many ways. 
Figure 8 shows how one can detect from a DEM if a terrain 
point is visible for an observer or not once both points, the 
terrain point and the observers point of view are known. With