Microtremor HVSR Study of Site Effects in the Ilirska Bistrica Town Area (S. Slovenia)

The region of Ilirska Bistrica is one of the most seismically active areas of Slovenia, where 15 damaging earthquakes with maximum intensity equal or greater than V EMS-98 have occurred in the last 100 years. These earthquakes have shown that strong site effects are characteristic of the parts of the town that are built on soft Pliocene clay and sand overlain by Quaternary alluvium. Since there is a lack of boreholes and geophysical and earthquake data, the microtremor horizontal-to-vertical spectral ratio (HVSR) method was applied to a 250 m dense grid of free-field measurements over an extended area and to a 200 m dense grid in the town area in order to assess the fundamental frequency of the sediments. Measurements were additionally performed in ten characteristic houses to assess the main building frequencies. The effects of wind and artificial noise on the reliability of the results were analyzed. The map of the fundamental frequencies of sediments shows a distribution in a range of 1–20 Hz. The lower frequency range (below 10 Hz) corresponds to the extent of Pliocene clays and sand overlain by alluvium, which form a small basin, and the higher frequencies to flysch rocks, but variations within short distances are considerable. The measurements inside the buildings of various heights (2–6 stories) showed main longitudinal and transverse frequencies in the range 3.8–8.8 Hz. Since this range overlaps with the fundamental frequency range for Pliocene and Quaternary sediments (2–10 Hz), the danger of soil-structure resonance is considerable, especially in the northern part of the town. Soil-structure resonance is less probable in the central and southern part of the town, where higher free-field frequencies prevail. These observations are in agreement with the distribution of damage caused by the 1995 earthquake (M_L?=?4.7, I_max?=?VI EMS-98), for which a detailed damage survey data is available.     

Vernacular museum: communal bonding and ritual memory transfer among displaced communities

Eclectically curated and largely ignored by the mainstream museum sector, vernacular museums sit at the interstices between the nostalgic and the future-oriented, the private and the public, the personal and the communal. Eluding the danger of becoming trivialised or commercialised, they serve as powerful conduits of memory, which strengthen communal bonds in the face of the ‘flattening’ effects of globalisation. The museum this paper deals with, a vernacular museum in Vanjärvi in southern Finland, differs from the dominant type of the house museum, which celebrates masculinity and social elites. Rather, it aligns itself with the small amateur museums of everyday life called by Angela Jannelli Wild Museums (2012), by analogy with Lévi-Strauss’ concept of ‘pensée sauvage’. The paper argues that, despite the present-day flurry of technologies of remembering and lavishly funded memory institutions, there is no doubt that the seemingly ‘ephemeral’ institutions such as the vernacular museum, dependent so much on performance, oral storytelling, living bodies and intimate interaction, nevertheless play an important role in maintaining and invigorating memory communities.