S U M M A R YThe Dinar earthquake (M S = 6.1) of 1995 October 1 killed 90 people and destroyed more than 4000 buildings. Despite the moderate size of the earthquake, the level of damage was extremely high, which led to many studies that were carried out in the region. The majority of these studies concluded that the main reasons for the damage were the construction errors and the poor soil conditions. However, at that time no appropriate soil condition map based on extended, high density measurements was available.Shear wave velocity is an important parameter for evaluating the dynamic behaviour of soil in the shallow subsurface. Thus site characterization in calculating seismic hazards is usually based on the near surface shear wave velocity values. The average shear wave velocity for the top 30 m of soil is referred to as V S 30 . For earthquake engineering design purposes, both the Uniform Building Code (UBC) and Eurocode 8 (EC8) codes use V S 30 to classify sites according to the soil type.The V s 30 values calculated by using multichannel analysis of surface waves (MASW) were used to create a new soil classification map of the Dinar region. Surface seismic measurements were carried out at 50 locations mostly in Dinar city and its surroundings. The dispersion data of the recorded Rayleigh waves were inverted using a Genetic Algorithm (GA) method to obtain shear wave velocity profiles of the investigated sites. Thus the derived V s 30 map of the Dinar region was transformed to the UBC and EC8 standards.Soil classification results show that most parts of the region, located in alluvial basin, have low shear wave velocity values. These values are within the range of 160-240 m s −1 and thus fall into the S D and S E categories according to the UBC and the C and D categories according to EC8. Within the region, some parts located on the hill zone and the transition zone have better soil conditions [corresponding to S C (UBC) and B (EC8) categories] and have comparatively high shear wave velocities in the range of 500-740 m s −1 and 350-450 m s −1 , respectively. V S 30 and soil classification maps were compared with the damage distribution associated with the earthquake. In possession of a detailed shear wave velocity map of Dinar City, in general, the results show that there is a correlation between the V S 30 values and the damage distribution of the region. In addition to the low V S 30 values, the likely causes of the damage were investigated, and it is observed that one of the major factors for high levels of damage is 3-D variations of geological structures.

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On 1 October 1995, the Dinar earthquake (Mw 6.1) devastated the city of Dinar in southwestern Turkey. We investigated the effects of geological conditions on the localized damage patterns using microtremor survey and multichannel analysis of surface waves. The microtremor survey was carried out in and around the Dinar basin to determine the resonance frequencies and depths of the sedimentary layer at 38 different locations using a broadband seismometer. The shear-wave velocity profile of the basin sediments was estimated from the inversion of the microtremor horizontal-to-vertical spectrum based on surface waves from seismic noise at each site using a genetic algorithm. The average shear-wave velocities estimated from the multichannel analysis of surface waves experiments were given as constraints in the inversion. A new relationship between the thickness of basin sediment and the main peak frequency in the horizontal-to-vertical spectral ratios was derived. This relationship allows a zonation of the Dinar region, which is consistent with previous studies and can be importantly used for the seismic hazard evaluation of the region.

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Two archaeologically unexplored mounds were studied in the area of the central Great Hungarian Plain. The age of the construction of the mounds was clarified on the basis of radiocarbon (14C) age determination of buried soil layers. Different, later-building phases of the mounds were detected by pedological and geo-electric analyses of the human-made layers. The age of the buried soils was corrected for the reservoir age of the recent soils found in the surroundings of the mounds. Radiocarbon ages of the carbon extracted from the soils at temperatures 400 and 800ºC were almost completely the same. Based on the calibrated ages of cal BP 4830–5270 (Szálka Mound) and cal BP 4880–5290 (Vajda Mound) of the buried soil layers, the identified kurgans were built by people of the Copper Age Yamnaya Culture. On the basis of the pedological and geophysical analysis of the layers, Szálka Mound and Vajda Mound were built in two and in three phases respectively from the chernozem-like humus-rich topsoil layers of the surrounding area. The former shallow quarry sites have been almost completely filled and cannot be identified at the foot of the mounds even using geodetic methods.