Resonance frequencies of unconsolidated sediments of the Iška alluvial fan (Ljubljana Moor basin) were derived using microtremor method. Free-field measurements were conducted in a grid with point spacing of approximately 250 m. The sediments frequency-thickness relationship, h = 202.97 f -1.139, was obtained on the basis of 107 microtremor measurements, six existing boreholes that reached the Pre-Quaternary basement and two seismic reflection profiles. The reliance of the obtained relationship was evaluated with the R2 coefficient, which shows a very good level of determination. The resonance frequency map reveals the existence of an N-S oriented deeper buried valley (maximum depth 119 m) in the Western part of the alluvial fan. The microtremor HVSR amplitude map does not show any specific spatial distribution pattern, with the exception of a relatively narrow band of low amplitudes located north of Iška vas. This is probably related to an area of severely fractured bedrock along the Mišji Dol fault. Map of the Quaternary sediment thickness and map of the Pre-Quaternary basement topography were constructed on the basis of the established relationship. The basement topography map shows rather steep western slopes of the buried valley down to deepest part, followed by a gradually ascending basement towards the Eastern part of the fan. The comparison of the obtained parameters a and b in frequency-thickness relationship with other sedimentary basins around the world reveals a small variation of b values, and a rather large range of a values, which implies that the parameter a is characteristic for certain geological areas. The results of this research will find use in constructing more accurate hydrogeological models and for assessment of possible sediments-structure resonance effects in seismic microzonation., Lovro Rupar and Andrej Gosar., and Obsahuje bibliografii
At the end of 2010 seven TM 71 extensometers, installed at or near the active faults in Slovenia, were in operation. Three of them are on the surface and four inside karst caves. The highest rates with stable sense of movements were observed on the Idrija fault. Average horizontal displacement rate was 0.24 mm/year. Short term rates were even greater and reached 0.54 mm/year. The Raša fault first experienced an uplift of the SW block of 0.16 mm/year, which was followed by a short-term down-slip of the same block at the rate of 0.37 mm/year. Later the sense of movement returned to uplift with a rate of 0.05 mm/year. The average horizontal displacement was 0.07 mm/year. The Kneža fault experienced very small average displacements (y=0.035 mm/year, z=0.03 mm/year and x=0.02 mm/year). Similar rates were observed in nearby Polog cave (y=0.015 mm/year, z=0.027 mm/year and x=0.016 mm/year), which is located close to the seismically active Ravne fault. For Kostanjevica cave, located near the Brežice fault, small average rates are characteristic (y=0.006 mm/year, z=0.017 mm/year and x=0.012 mm/year). In Postojna cave, located close to the Predjama fault, two monitoring sites are very stable with small tectonic movements, including general dextral horizontal movement of 0.05 mm from 2004 to 2010 (Postojna 1) and two significant short-term peaks of 0.08 mm (Postojna 1-y and Postojna 2-z)., Andrej Gosar, Stanka Šebela, Blahoslav Košťák and Josef Stemberk., and Obsahuje bibliografii