Marisia - Maros Megyei Múzeum Évkönyve 31/1. (2011)
Articles
294 К. László-A. Péntek-L. Lenkey ever existed, disappeared probably because of landslide. This burnt red earth stripe from the western side continued until the southern corner. In the inner part of the fort fragments of a stone based surface construction were identified (Horedt 1957,176-179). The 90 x 60 m fort is limited on its eastern and western side by steep slopes, probably with this can be explained the fact that on the western side, only the burnt earth stripe appears, while on the eastern side, only the stone pavement was found. The research in 1956 concentrated on the plateau outside the fort and with this the six-year long excavations ended for quite a long time. After the processing of the finds, the results of the excavations were published by K. Horedt in two separate volumes (Horedt 1979; Horedt 1984). The excavation done by D. Protase in 1985-1986 and 1989-1991 in Moresti did not affect the hillfort (Protase Et Al. 1988, 287-297; Protase 1999,265-272). Geophysical methods The most frequently used geophysical method in archaeological research is the magnetic surveying (David 1995; Schmidt 2007). In general, magnetic measurements aim to determine the location and depth of buried magnetic objects (Telford Et Al. 1990). The materials most suitable for magnetic prospecting are the volcanic rocks, brick, potteries and other types of burned clay, and of course iron. The soil also contains magnetic minerals, and if the structure of soil is disturbed, then it results in the change of its magnetic properties. Therefore, trenches, graves, foundations of walls can also be detected by magnetic measurements. The magnetic field of an object has simultaneously a positive and a negative part, both belonging to the same object, similarly to a magnetic compass (PI. 1/3). Very often the vertical gradient of the magnetic field is measured. The vertical gradient gives the rate of the change of the magnetic field in vertical direction. The vertical gradient is more sensitive to the field of near surface objects, and it results in a sharper picture than the magnetic field itself. The magnetic anomaly field or the vertical gradient is shown in maps. In many cases it is worth to apply different geophysical methods, because they are sensitive to different material properties. The results can support each other and help the interpretation. The geoelectric methods aim to determine the electric resistivity or conductivity of the subsurface materials (Telford Et Al. 1990). In Moresti we applied the direct current geolectric method to obtain the resistivity distribution along a vertical section. This method is more time consuming than the magnetic method, therefore it is mainly applied after the magnetic survey in order to clarify some details. Its other advantage is that it provides the depth of the objects in a more direct way than the magnetic method. Field work The survey area was delineated based on the map of K. Horedt (1957) showing the structure of the fort (Fig. 2). We did not know the exact position of the fort; therefore a larger area was prospected. We were not able to measure until the edge of the slopes, because these sides were covered by dense bushes. The survey area was restricted to the open areas, which are still under use. Therefore the tip of the hill, where the centre of the fort was located, was left out of the survey. We used Overhauser magnetometers to measure the vertical gradient of the magnetic field in a rectangular grid with spacing of 1 m. Based on the results of the magnetic survey one geoelectric section was measured. Its location was established to cross the main structures visible in the magnetic map (PI. 1/3).
