Shear wave velocity estimation in the metropolitan area of Málaga (S Spain)

We carry out a seismic noise study based on array measurements at three sites in the Málaga basin, South Spain, for the further estimation of shear wave velocity profiles. For this purpose, we use both the H/V method and the f–k technique in order to characterize the different materials present in the zone, i.e., Quaternary sediments and Pliocene sedimentary rocks above the bedrock. The H/V analysis shows frequency peaks going from 1 Hz, in areas close to the border of the basin, to 0.3 Hz in places located toward the center of the formation. The f–k analysis allows obtaining the dispersion curves associated with each site and subsequently, estimating the Vs profiles by inversion of the respective group velocities. In this way, the basin basement can be characterized by S-wave velocities greater than 2000 m/s. Regarding the basin fill, it is divided into three layers defined by different wave velocity intervals. The shallowest one is featured by velocities ranging from 150 to 400 m/s and comprises the Quaternary sediments, while velocities going from 550–700 to1200–1600 m/s characterize the two underlying layers composed by Pliocene sediments. Finally, the information provided by the three Vs profiles is integrated in a 2D cross-section of the basin to have a spatial view of its sedimentary structure. The results obtained here, in addition to providing useful information about the infill of the basin near the metropolitan area of Málaga, will be very helpful for future seismic zonation studies in the region.

New York, April 1990: A Photographic Record

Aquestes fotografies de Nova York i de Boston, totes en blanc i negre, es van fer en abril del 1990, amb una cambra rèflex Asahi Pentax Spotmatic II amb objectiu de 50 mm, tot fent servir negatius Kodak Safety Film 5063. El Museu de la Universitat d’Alacant en conserva una col·lecció completa; vuitanta-set còpies fotogràfiques de 32 x 24 cm amb tintes Ultrachrome sobre paper Ilford Gold Fibre Silk de 310 gr/m² realitzades al “Estudio Paco Mora” de València l’any 2015, amb digitalització prèvia a partir dels negatius originals mitjançant un escàner Haselblad Flextight X 1 a una resolució de 3.200 punts per polzada.