Qualità di alcuni acquiferi dell\'altopiano carbonatico dei monti lessini veronesi (VR)

ItVengono esposti i risultati di un’indagine sulla qualità degli acquiferi, prevalentemente carsici, di un’ampia porzione centromeridionale dei Monti Lessini Veronesi. Nell’arco di 5 mesi (autunno-inverno 2000 ed inverno-primavera 2001) sono stati prelevati n° 130 campioni d’acqua da 16 sorgenti distribuite a varie quote. Su ogni campione sono state eseguite analisi chimiche e/o microbiologiche che hanno permesso di valutare la qualità delle acque oggetto di studio. Inoltre, ad ogni prelievo sono stati registrati i principali parametri fisici. In tutti i campioni è stata rilevata la presenza, anche massiccia, di coliformi totali mentre i valori dei parametri chimico-fisici rientrano, per lo più, nei limiti stabiliti per le acque potabili.EnThis study presents the findings of a research about the quality of the aquifers mainly of karst nature in a large, Center-South area of the Lessini Mountains (Verona). The study has been realised jointly by the Civic Museum of Natural History, and the IPSIA "E. Fermi".The former has been studying the main springs and their hydrogeological asset of the Veronese plateau since 1997. Over a period of five months (Fall-Winter 2000, and Winter-Spring 2001), one hundred and thirty (130) samples of water have been taken from sixteen (16) springs situated at different heights. Each sample has been chemically and microbiologically analysed in order to evaluate the quality of the waters

Tanella cave (Monte Baldo-Verona, Italy): a record of environmental data on the last glacial period

Since 2003, an extensive hydrogeological investigation has been carried out on Monte Baldo, in order to make a census of springs occurring along the west side of the mountain and to evaluate the quality of their water. The investigation included morphological and hydrogeological observations concerning the Tanella cave and interdisciplinary investigations performed on the deposits found in the cave. This paper shows the first data concerning the hydrogeology of the cave, as well as data on stratigraphy, pollen and micro-charcoals obtained from the analyses of a well preserved sequence located at ca. 80 m from the entrance (sequence A). The aim of the study was to reconstruct the environment of the area around the cave along the time span testified by the sequence. The sequence is 60 cm thick and was built up by fluvioglacial sediments followed by lacustrine sediments. Five samples taken along the sequence plus three recent control samples (mosses), collected in places assumed as origins of the pollen input, were studied for pollen and micro-charcoals. Pollen preservation was good and concentration varied from 101 to 103 p/g. Pollen spectra from the cave showed the evolution from a landscape of alpine grassland above the timberline, likely of glacial age, to a more forested Holocene landscape similar in flora to the current one testified by the control samples. Pollen probably arrived in the cave by air, water and animals and from plants growing near the cave. It appears to have been continuously underwater after its deposition due to its very good state of preservation. Micro-charcoals suggested that fires were sometimes lit near the cave

A Synoptic Review of the Eocene (Ypresian) Cartilaginous Fishes (Chondrichthyes: Holocephali, Elasmobranchii) of the Bolca Konservat-Lagerstätte, Italy

Here, we review and discuss the records and taxonomy of the Ypresian (Eocene) chondrichthyans from the famous Bolca Konservat-Lagerstätte in northeastern Italy. Despite the outstanding diversity and the numerous studies focusing on the actinopterygian faunas from Pesciara and Monte Postale, the current knowledge about the systematics, taxonomy and phylogenetic relationships of the cartilaginous fishes from these Eocene sites remains elusive and largely inadequate. The celebrated Eocene Bolca Lagerstätte has yielded several exquisitely preserved articulated remains of chondrichthyan fishes in which delicate structures and soft tissues are preserved, as well as isolated teeth. The cartilaginous fish assemblage of Bolca comprises at least 17 species-level taxa belonging to 10 families in 6 orders, including selachians (Carcharhiniformes, Lamniformes), batoids (Torpediniformes, Myliobatiformes, Rajiformes) and holocephalans (Chimaeriformes). The occurrence of holocephalans represented by an isolated fin-spine of the chimeroid Ischyodus in the Bolca assemblage is reported here for the first time and represents the first record of chimeroids in the Eocene of Italy and also southern Europe. The Bolca chondrichthyan assemblage is remarkably different from those of other contemporaneous Boreal or Tethyan deposits, suggesting that its taxonomic composition is largely influenced by the palaeoenvironmental context. However, this synoptic review also highlights the importance of detailed revisions of all chondrichthyan remains from the Bolca Konservat-Lagerstätten

Le lave a cuscino di Alcenago. Evidenze di attività magmatica sottomarina in Valpantena

A partire dal Paleocene superiore (circa 60 milioni di anni fa) fino all’Oligocene (circa 30 milioni di anni fa), gran parte del Veneto occidentale, compresi i Monti Lessini Veronesi, fu interessato da una intensa attività magmatica prevalentemente sottomarina, che si manifestò in modo intermittente con numerose fasi vulcaniche (Piccoli 1965). Le lave a cuscino, note anche come “pillow lave” si formano in concomitanza di eruzioni subacquee per contatto tra la lava e l’acqua, in ambiente prevalentemente marino, ma anche per eruzioni subglaciali. Le lave a cuscino di Alcenago (Valpantena, Verona), oggetto della presente nota, sono ben esposte per una cinquantina di metri in lunghezza lungo la direzione NNO-SSE in prossimità del secondo tornante di Via Chiesa, la strada che conduce al paese. Si tratta, certamente, di uno dei pochi affioramenti del Veronese in cui si distinguono molto bene i singoli cuscini e i rapporti tra gli stessi e il substrato sedimentario sul quale si sono deposti