Geophysical Investigation of the Depression System of a Carbonate Terrain

The study area is located at the transition zone between the Alps and Carpathian basin. Structurally it is a foothill of the Eastern Alps where the chrystallin rocks of Sopron Mountains are covered by Badenian and Sarmathian sediments. Its central part is composed of Lajta limestone. This plateau-like carbonate terrain is called Balf-block. Detailed geomorphological mapping explored unusual, active depression systems. The characteristic curved edge depressions-like forms reminding of collapse dolinas are grouped in depression systems. The origin of these landforms could not be clarified purely on the basis of the surface, field observation and morphological analysis. The geological structure of the area, the relations between geological structure and the location of depression systems were in detail examined. Subsurface conditions were also investigated by different geophysical methods. Considering the physical properties of the limestone and possibilities offered by the terrain geoelectric, electromagnetic and geomagnetic methods were applied. In lack of final geological and geophysical evidences industrial archaeology records were also searched for. Beside the clarification of the origin and expected future development of morphological forms the further aim of this study is to provide methodological aspects for characterisation of landforms, detection of underground cavities and buried objects in similar environment.