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In Sardinia, no active hypogenic caves have yet been discovered or described. Although there are a few thermal springs, mostly correlated to Quaternary volcanic activity, none of these thermal waters have interacted with carbonate rocks. Nevertheless, in the SW of the Island many metal ore deposits hosted in Cambrian limestones have been exploited over the last two centuries, allowing the discovery of so-called mine caves, some of which are clearly of hypogenic origin. These caves formed by thermal waters in a phreatic setting and are now located far above the water table and are no longer active, apart from some recent dripstone formation. The mine tunnels in Mount San Giovanni, near Iglesias and Gonnesa towns, have cut most of these caves: among them the well-known Santa Barbara cave, covered with barite crystals, Santa Barbara 2 cave, with its unique oxidation vents, and Crovassa Ricchi in Argento. Other hypogenic caves have been discovered in the mines of Campo Pisano and Monteponi (Iglesias), Mount Onixeddu (Gonnesa), and especially Masua (Iglesias). A very special case of hypogenic cave is the Corona ’e Sa Craba quartzite system, known for its barite crystals and rich in many mineral species. This chapter summarizes these known inactive hydrothermal and sulfuric acid caves.

In the era of networks, it is clear that the idea of local environmental protections also cannot be considered apart from the global dynamics. With this consideration it becomes more vital the necessity for adapting politics for the governance of protected natural areas. Wise plans are the first experiments in Europe to create the energy sustainable communities through energy saving and implementation of renewable energies. The project constitutes Italy, Spain, Galles and Sweden with a common effort to elaborate the guidelines of a base on a further elaboration for local energy plans. This essay analysed the first conclusions of the case study for Italy.: the Community of the Regional Park of Ticino., Ri-Vista, Vol 8 No 2 (2007)

Introduzione al volume Grotte di Miniera

This note presents a preliminary mineralogical study of the skarn-hosted Monte Guisi Cave in SW Sardinia (Italy). X-ray diffraction (XRD) and environmental scanning electron microscope (including energy dispersive X-ray spectroscopy microanalysis; EDS) analyses allowed us to identify some uncommon cave minerals such as: cerussite PbCO3, rosasite (Cu,Zn)2(CO3)(OH)2, dundasite PbAl2(CO3)2(OH)4·H2O), brochantite Cu4SO4(OH)6, cuprite Cu2O, hemimorphite Zn4Si2O7(OH)2·H2O, chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O, shattuckite Cu5(SiO3)4(OH)2, and plancheite Cu8(Si4O11)2(OH)4·H2O. Dundasite and plancheite are for the first time reported as cave minerals. All these species appear to represent oxidation/hydrolysis products of the primarily Pb-Zn and Cu-rich ore mineralization that impregnates the carbonate bedrock.

In the past few years the systematic study of caves intercepted by mine workings in southwest Sardinia has permitted us to observe morphologies due to rare speleogenetic and minerogenetic processes related to ancient hydrothermal activity. These relic morphologies are slowly being overprinted by recent speleogenetic processes that tend to obscure the hypogene origin of these caves. A combined geomorphological and mineralogical investigation has permitted a fairly detailed reconstruction of the various phases of evolution of these caves. Cave formation had already started in Cambrian times, but culminated in the Carboniferous, when most of the large voids still accessible today were formed. A key role in carbonate dissolution was played by sulphuric acid formed by the oxidation of the polymetallic ores present in the rocks since the Cambrian. During the Quaternary a variety of minerals formed inside the caves: calcite and aragonite, that yielded sequences of palaeo-environmental interest, and also barite, phosgenite, hydrozincite, hemimorphite and many others. These minerals are in part due to a phreatic thermal hypogenic cave forming phase, and in part to later epigene overprinting in an oxidizing environment rich in polymetallic ores. Massive gypsum deposits, elsewhere typical of this kind of caves, are entirely absent due to dissolution during both the phreatic cave formation and the later epigenic stage.

In the past few years the systematic study of caves intercepted by mine workings in southwest Sardinia has permitted us to observe morphologies due to rare speleogenetic and minerogenetic processes related to ancient hydrothermal activity. These relic morphologies are slowly being overprinted by recent speleogenetic processes that tend to obscure the hypogene origin of these caves. A combined geomorphological and mineralogical investigation has permitted a fairly detailed reconstruction of the various phases of evolution of these caves. Cave formation had already started in Cambrian times, but culminated in the Carboniferous, when most of the large voids still accessible today were formed. A key role in carbonate dissolution was played by sulphuric acid formed by the oxidation of the polymetallic ores present in the rocks since the Cambrian. During the Quaternary a variety of minerals formed inside the caves: calcite and aragonite, that yielded sequences of palaeo-environmental interest, and also barite, phosgenite, hydrozincite, hemimorphite and many others. These minerals are in part due to a phreatic thermal hypogenic cave forming phase, and in part to later epigene overprinting in an oxidizing environment rich in polymetallic ores. Massive gypsum deposits, elsewhere typical of this kind of caves, are entirely absent due to dissolution during both the phreatic cave formation and the later epigenic stage. Copyright © 2013 John Wiley & Sons, Ltd.

The morphological knowledge of the territory, bothin its surface and subterranean aspects, is the main premise to all decision-making procedures as well as all planning and management activities. Knowledge takes shape into reliable precise and complete thematic cartography and databases, whichare necessary for anybody dealing withunderground contexts: speleologists, scientists, public administrations, managing authorities etc. Surveys in caves are normally carried out withtraditional techniques and instruments, whichare essential for a first representation but not enoughfor a pragmatic effective topographic approach. Laser scanning technique can be an alternative to the traditional systems. Laser scanning quickly acquires the shape of cavities as “point clouds” (x, y, z coordinates and colour values) and produces a highprecision database of the surveyed object. Laser scanning technology is therefore a feasible way to document caves in a precise exhaustive way, limiting risks relating to lack and/or inadequacy of data. The present paper explains the laser scanning survey carried out in San Giovanni mine near Iglesias (Sardinia, Italy), particularly in Santa Barbara and Santa Barbara 2 caves, the data post-processing and three-dimensional modelling of “point clouds” (operations performed witha dedicated software), and the use of the obtained digital model. Moreover, the paper describes the advantages of laser scanning for the hypogean survey in comparison to traditional methods and the future potentialities of a broad application of laser scanning instruments in caves.

The research has been examining the ancient but still current reports from standard and economy with particular reference to the Italian labor law. The crisis in which the labor law is entered the lawyer poses new problems: the need for business flexibility competes hard against the achieved stability of the protection of worker. The dialogue between standard and economy plays a vital role in the mechanisms of regulation of social relations seconds patterns do not always equal, in which prevails on the traditional concept of the effectiveness of the right economic strength of the law. What effect will produce on traditional labor law? What may be the result of training is not always clear In this chaotic context, in which the rules are produced as if they were goods, shows the need for tools capable of giving certainty to the subjective circumstances of workers. No surprise then that during the decoding can be applied to the old general clauses of good faith and fair, able to attract in the contract, increasing instrument for regulating the relations between individuals, the values of the time change and protect the rights of workers against the many manifestations of distorted power business.

This study compares minor and trace element variation in two speleothems from two caves of southwestern Sardinia (Italy), in order to verify the role of some elements in calcite growth inhibition and aragonite precipitation. The first sample is a drapery from a cave hosted in dolostones. The second is a flowstone from a natural cave intercepted by a gallery of a mixed sulphide mine. In the first sample, Mg concentration in the calcite layer is high just above the underlying aragonite, it shows a minimum in the middle of the calcite, and it increases to a maximum just below the overlying aragonite. The Mg variation in this depositional sequence suggests that aragonite forms when calcite growth is inhibited by Mg because of a greater Mg/Ca ratio in solution. We infer that climatic conditions evolved from drier to wetter for the transition aragonite-calcite, and then from wetter to drier for the transition calcite-aragonite. This hypothesis is supported by inverse correlation of P with Mg in the calcite layer. In the second sample from a mine cave, the inhibitory effect of Mg on calcite deposition cannot explain the appearance of aragonite, because Mg concentration is small in the calcite layer and even decreases in the upper part, nearest the overlying aragonite. Zinc concentration, which is greater than that of Mg, increases abruptly in calcite toward the aragonite layer, reaching its maximum just below the aragonite. Thus, in this case, calcite inhibition seems to be induced by Zn. An increase of the Zn/Ca ratio in calcite can be simply explained by an increase of dissolved Zn in the fresh (not residual) feeding water, due to greater oxidation of sulphides in wetter periods. This hypothesis is supported by positive correlation of Zn with P, Pb and Cd. If the presence of aragonite in the mine cave is truly controlled by the Zn/Ca ratio rather than the Mg/Ca ratio, aragonite could reflect wetter conditions rather than drier ones, counter to conventional understandings from caves where Zn is less abundant.

Karst in Emilia Romagna region (N-Italy) is mainly developed in Messinian gypsum rocks that outcrop on less than 1% of the regional territory. The numerous epigenic caves that have been discovered in these rocks are believed to have formed in the last ten thousands of years, with some having started developing before the LGM. Remnants of intra-Messinian karst cycles have been discovered in both open pit and underground quarries, at Monticino (Vena del Gesso) and Zola Predosa (West of Bologna) respectively. At Monticino karstified fissures are filled with Upper Messinian sediments containing a rich association of vertebrates. These animals lived on the emerged and karstified gypsum outcrops. At Zola Predosa, instead, a rather extensive cave system, now completely filled with sediments, confirms that this karst cycle has lasted long enough to enable the formation of well-developed underground karst networks. The Intra-Messinian karst cycle was active at the beginning of the major tectonic events that have brought the gypsum ridges of Zola Predosa to incline for over 40º.

Many quarries for the extraction of gypsum are located in the hills of the Monferrato area (central eastern Piedmont). Close to the village of Moncalvo, Asti Province, a subterranean quarry of more than 20 km long is present. During the excavations a fracture from which water gushed at a pressure of 3 atm has been intercepted in 2005. The underground works have been suspended immediately and, after only a few hours a water flow comprised between 3000 and 4000 L s-1 has flooded the quarry tunnels filling a volume of over 60,000 m3. After more than one month of pumping the flooded areas have been made accessible again, revealing a thin rock diaphragm that separated the quarry tunnel from a natural cave, which failed under the high hydraulic pressure. Through this small gap it has been possible to access an extensive karst network that previously was completely submerged. During the following quarry operations a second natural cave has been encountered, belonging to the same system but physically divided from the first cave by some metres of physical sediments. The total development of this cave system is around 1 km. The exploration of these caves has allowed to gather an interesting set of observations that have contributed to elaborating a speleogenetic model. The first information regards the impressive amount of snottites present along the walls of the caves, and the overall thickness of gypsum rock subdued to weathering, reaching up to 30 cm. There are many morphologies that clearly demonstrate the caves being formed in phreatic conditions, such as pendants and corrosion cupola, but also flat corrosion bevels and V-shaped cross-sections, further evidences of formation in saturate conditions. The stratigraphic asset of the area surely has played a fundamental role in the formation of these karst systems. From bottom to top there is a thick shale sequence, and a thin discontinuous and extremely well karstified marly limestone bed that seemed to have enhanced the hydrological flow in the above lying gypsum beds. The principal cave systems are formed in between the first and second bed of gypsum, along a shaly finely stratified interbed rich in organic material. On the floor of the main passage there are many rather small subvertical conduits that develop up to the underlying limestone bed thus favoring the upward movement of water and the dissolution of the gypsum rocks. The subterranean excavations also have intercepted other caves, most of them of much smaller size, often reaching some cubic metres in size and partially filled with large gypsum crystals, grown by the continuous but slow feeding of slightly supersaturated waters.

Nell’ambito del PRIN 2001-2003 “Studio morfologico e genetico di speleotemi di particolari ambienti carsici italiani e dell’America centro-meridionale” sono stati effettuati alcuni campionamenti di acque all’interno del Monte San Giovanni (Iglesias-Gonnesa), che racchiude l’omonima miniera di Pb e Zn, oggi dismessa, e che custodisce una delle più belle grotte di miniera che si conoscano, la grotta di Santa Barbara, attualmente aperta al pubblico grazie agli sforzi ed all’impegno profusi dall’IGEA (Interventi Geo-Ambientali) S.p.A. di Iglesias. Il principale scopo dello studio era fornire i primi dati sulla composizione chimica delle acque di stillicidio, in relazione ai depositi chimici attualmente in formazione ed a quelli antichi. Oltre al chimismo di base ed ai principali parametri chimico-fisici, è stato determinato il contenuto in soluzione di numerosi elementi minori ed in tracce, prestando particolare attenzione ai metalli (p.es. Pb, Zn) contenuti nella mineralizzazione, ed a quegli elementi (p.es. Mg, Sr, Ba) che possono influenzare la tipologia del deposito chimico in formazione. La determinazione dello stato termodinamico delle acque, attraverso calcoli di speciazione e saturazione eseguiti al computer col programma PHREEQC, ha consentito di modellizzare i processi di interazione acqua-roccia in atto, e di simulare le condizioni geochimiche che nel passato hanno portato alla formazione di depositi chimici di grotta peculiari, come quelli costituiti da idrozincite.

Il Parco Geominerario Storico ed Ambientale della Sardegna mette sotto tutela e valorizza il grande patrimonio ed il caratteristico paesaggio minerario dell'Isola. Molte delle più importanti miniere della Sardegna sono ubicate nelle rocce carbonatiche cambriane dell’Iglesiente. In quest’area il grande sviluppo delle gallerie minerarie ha permesso di intersecare importanti fenomeni carsici profondi con nessuna naturale connessione con l’esterno: le cosiddette “Grotte di Miniera”. Queste presentano elementi di eccezionale interesse speleologico e minerogenetico, come evidenziato anche dagli studi effettuati nell’ambito del COFIN 2001-2003. Sebbene le grotte di miniera in Sardegna siano state oggetto di esplorazioni speleologiche per oltre un ventennio, soltanto in questi ultimi dieci anni sono state intensificate le esplorazioni speleologiche che hanno consentito di scoprire o “riscoprire” oltre 100 cavità naturali accessibili esclusivamente grazie alle gallerie minerarie. La più importante e rinomata grotta di miniera è senz’altro la Grotta di Santa Barbara nel Monte San Giovanni presso Iglesias, oggi aperta al pubblico e gestita dall’IGEA S.p.A. (Interventi Geo-Ambientali) di Iglesias. Vengono qui illustrati gli aspetti scientifici più interessanti di queste particolari grotte che meritano di essere adeguatamente studiate e salvaguardate. Alcune di queste, inoltre, possono divenire delle attrattive per un turismo culturale e scientifico che ben si inserisce nell’ambito delle attività del Parco Geominerario.