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Onac B.P.,University of South Florida | Fornos J.J.,University of the Balearic Islands | Merino A.,Grup Espeleologic de Llubi | Gines J.,Federacio Balear dEspeleologia | Diehl J.,University of South Florida
International Journal of Speleology

Cova des Pas de Vallgornera (CPV) is the premier cave of the Balearic Archipelago. Over 74 km of passages develop within two carbonate lithofacies (reef front and back reef), which ultimately control the patterns of the cave and to some degree its mineral infilling. The diversity of speleothem-forming minerals is four times greater around or within hypogenerelated features (vents, rims, cupolas), compared to any other vadose passages in the cave. The mineralogy of speleothems (crusts, nodules, crystals, earthy masses) associated with hypogene features in the seaward upper maze of Sector F is characterized by the presence of aragonite, ankerite, huntite, clay minerals, and quartz. In the Tragus and Nord sectors, however, the dominant mineral is dolomite, along with aragonite, celestine, huntite, clay minerals, and quartz. Calcite is by far the most ubiquitous mineral throughout the cave. Detailed macroscopic and scanning electron microanalysis and imaging have permitted the investigation of textural relationships between the minerals associated with vents, rims, and vent's roof and walls. These studies along with morphological and stable isotope analyses confirm that not all minerals are connected with a hypogene stage in the cave evolution, and furthermore, none of them appears to be sulfuric acid by-products. Instead, the mineral assemblages documented in speleothems from CPV clearly support at least three speleogenetic pathways, namely seacoast mixing, ascending of warm groundwaters, and meteoric recharge (vadose). Thus, cave minerals in Cova des Pas de Vallgornera hold the keys to reconstruction and understanding of processes and conditions under which they precipitated, allowing to establish their relationship with various speleogenetic pathways. Source

Gines J.,Federacio Balear dEspeleologia | Fornos J.J.,University of the Balearic Islands | Gines A.,Federacio Balear dEspeleologia | Merino A.,Grup Espeleologic de Llubi | Gracia F.,Federacio Balear dEspeleologia
International Journal of Speleology

The flat areas of eastern and southern Mallorca host a remarkable coastal karst, where Cova des Pas de Vallgornera stands out due to its length (more than 74 km) and its special morphological suite. The pattern of the cave is quite heterogeneous showing sharp differences produced by the architecture of the Upper Miocene reef: spongework mazes and collapse chambers dominate in the reef front facies, whereas joint-guided conduits are the rule in the back reef carbonates. Regarding the speleogenesis of the system, a complex situation is envisaged involving three main agents: coastal mixing dissolution, drainage of meteoric diffuse recharge, and hypogene basal recharge related to local geothermal phenomena. The cave system is disposed in two main tiers of passages, of which geomorphologic interpretations are derived from their elevation data. The evolutionary trends as well as the chronology of the different cave sections are difficult to establish owing to the frequent shifting of the coastal base level during the Plio-Quaternary. In this respect, the genesis and evolution of the cave were fully controlled by sea-level fluctuations in the Western Mediterranean basin, with the main phases of cave formation, based on vertebrate paleontological data, going back to mid-Pliocene times. Source

Bover P.,CSIC - Mediterranean Institute for Advanced Studies | Bover P.,University of Adelaide | Bover P.,American Museum of Natural History | Valenzuela A.,CSIC - Mediterranean Institute for Advanced Studies | And 9 more authors.
International Journal of Speleology

The Cova des Pas de Vallgornera is the longest cave of Mallorca (Balearic Islands, Western Mediterranean) and one of the 30 longest caves in the world. The exploration of one of the galleries allowed the discovery of a fossiliferous deposit of vertebrate remains in a remarkable preservation state. The fossil faunal complex found in this gallery is composed of up to 5 mammalian species (Myotragus aff. kopperi, Hypnomys onicensis, Nesiotites aff. ponsi, Rhinolophus aff. mehelyi and Pipistrellus sp.), at least 14 bird species (among them two Mallorcan endemic taxa: Pica mourerae and Athene vallgornerensis), one reptile (Podarcis aff. lilfordi) and one amphibian (Discoglossus sp.). This faunal composition is similar to the one recorded in the Pedrera de s'Ònix, a well known deposit from the Early Pleistocene of Mallorca, and shared morphological characteristics between taxa of both deposits suggest that the chronology of the Cova des Pas de Vallgornera should be considered Early Pleistocene as well. Both taxonomical analysis and chronology of this fauna furnished information on some speleological aspects of the cave. Source

Merino A.,Grup Espeleologic de Llubi | Mulet A.,Grup Espeleologic de Llubi | Mulet G.,Grup Espeleologic de Llubi | Croix A.,Seccio dEspeleologia Voltors OJE | And 4 more authors.
International Journal of Speleology

The Cova des Pas de Vallgornera lies in the Llucmajor municipality, in southern Mallorca, and is the longest cave in the Balearic Islands. Currently its surveyed length is over 74,000 m, including more than 17,000 m of underwater extensions. The cave was discovered accidentally in 1968, but it was in 2004 when a major breakthrough shed light on its real extension and importance. The cave roughly shows two tiers of passages, apart from the underwater extensions, the first one is between 7 and 11 m above the mean sea level, the second one is about at the water table level. The importance of the cave is not only related to its extension, but also to the presence of a wide variety of speleothems and outstanding solutional morphologies that evidence a complex evolution. The cave is under the protection of Conselleria de Medi Ambient, Govern de les Illes Balears (the Regional Environmental Authority) and was declared Site of Community Importance, within the Natura 2000 Network. Source

Merino A.,Grup Espeleologic de Llubi | Gines J.,Federacio Balear dEspeleologia | Tuccimei P.,Third University of Rome | Soligo M.,Third University of Rome | Fornos J.J.,University of the Balearic Islands
International Journal of Speleology

The abundance and variety of speleothems are undoubtedly among the remarkable features of Cova des Pas de Vallgornera, the longest cave system in Mallorca Island developed in the eogenetic karst of its southern coast. Due to the monotonous carbonate lithology of the area, most of the speleothems are composed of calcite and in a few cases aragonite, although other minerals are also represented (e.g., gypsum, celestine, barite). However, in spite of the rather common mineralogy of the speleothems, its distribution results strongly mediated by the lithologic and textural variability linked to the architecture of the Upper Miocene reefal rocks. Apart from a vast majority of speleothem typologies that are ubiquitous all along the cave system, some particular types are restricted to specific sections of the cave. In its landward inner passages, formed in the low permeability back reef facies, a great variety of speleothems associated to perched freshwater accumulations stands out, as well as some non frequent crystallizations like for example cave rims. On the other hand, the seaward part of the cave (developed in the very porous reef front facies) hosts conspicuous phreatic overgrowths on speleothems (POS), which are discussed to show their applications to constrain sea level changes. The factors controlling the distribution of speleothems found in Cova des Pas de Vallgornera are discussed along the paper, focusing the attention on the lithologic, hydrogeologic, and speleogenetic conditionings; at the same time some uncommon speleothems, not found in any other cave in Mallorca, are also documented from this locality. Finally, a cognizant effort has been undertaken to illustrate with photographs the most remarkable speleothem types represented in the cave. Source

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