Mallorca's Caves and Coves

MONOGRAPH The Enchanted Cove MALLORCA’S CAVES AND COVES THE GENETIC AND HYDROLOGICAL RELATIONSHIP BETWEEN COVES AND CAVES FRANCESC GRÀCIA, BERNAT CLAMOR, PERE GAMUNDÍ, JOAN J. FORNÓS AND DAMIÀ VICENS The exploration and documentation of the coastal caves in Migjorn, Mallorca –many of which have large underwater galleries– would suggest a genetic and hydrological relationship between these coves and endokarst. These caves are an essential part of Mallorca’s natural heritage. To begin with we should point out, as Rosselló stated for these caves, which considers the formation of (2005), that if we move from the toponymic –or primordial voids, caused by dissolution in the water popular– ambit to the scientifi c one, not all coves table due to the aggressiveness of the mixture of are calas (coves) strictly speaking, nor all those fresh inland waters and marine waters within highly called so. On the one hand, authors such as Gràcia permeable rock, given signifi cant primary porosity. et al. (2011) deduced from the collapse of the roof Many of the galleries and chambers forming these of a cave forming a more or less narrow and long cavities are now located below sea level and have kind of inlet called a caló. On the other hand, many been invaded by water. It is very interesting that coastal cavities are related to seawater fl ooding of there are different levels of cavities, corresponding to varying proportions. Rosselló et al. (2002) discuss different periods of speleogenesis. The planimetric the complexity at the average pattern of caves like these would scale of the east coast of indicate the somewhat random Mallorca and southern Menorca, coalescence of more or less «COASTAL KARST CAVITIES precisely by the concurrence independent units, which have of coves and caves in Upper APPEAL TO TRAVELLERS AND grown three-dimensionally, Miocene limestone, which NATURALISTS, ESPECIALLY connecting with each other are very sensitive to karst- AFTER THE DISCOVERY OF to give rise to a branching driven evolution. The coves are THE CURRENT TOURIST formation. associated with the mouths of Besides the aforementioned ATTRACTION COVES DEL river courses, but their shapes caves resulting from marine may have been affected by DRAC» abrasion –non-karst– a type subsidence, driven by fracture of cavity abounds on the and karstic dissolution processes coast, which is the result of that have occurred at different levels. the caves being captured within the coastal mixing zone, namely, karstic processes, due to the eating away of cliffs by sea-driven mechanical erosion. ■ COASTAL NOTCHES IN MIGDIA DE MALLORCA Given the combination of processes, these caves are Notches and hollows generated by coastal erosion known as karstic-marine captures. Quite complex processes, namely caves related to marine abrasion, sedimentary deposits abound, which are interspersed abound along the coast, although they are often by speleothems (mineral deposits) with ossiferous rather modest in size. Moreover, the most important deposits of terrestrial vertebrates and marine detritus, coastal karst cavities belong to the type of caves in which provide chronological records of great interest. the coastal mixing zone. Indeed, these are the type These deposits depend entirely on Quaternary appealing to travellers and naturalists, especially variations in sea level, due to glacio-eustatic factors. following explorations carried out for over a century The current Mediterranean sea level is also a factor in the tourist attraction Coves del Drac, namely determining the existence of underground lakes of «Dragon’s caves», in the Manacor municipality. In brackish groundwater, which fi ll lower reaches of the recent decades, a genetic model has been put forward caves. 2013 MÈTODE Annual Review 97 MONOGRAPH The Enchanted Cove During the Pleistocene, glacio-eustatic sea level declines precipitated the collapse of cave walls and vaults, while later extreme phases of speleothem deposition contributed to masking the 2 characteristics of primeval cavities and collapsed matter. It should be noted that the magnitude of the rock fall and mechanical alteration of the rock mass largely determines the appearance of most galleries and cavities, while also being responsible 4 for the formation of exterior openings due to surface subsidence. In Mallorca these formations are known as abisaments in the Manacor region and esfondrats in Ses Salines. Meanwhile other galleries, usually found in less permeable rock dating to the Upper Miocene, are hardly affected by subsidence and here water corrosion morphology dominates, as in the case of external lagoon facies. 3 ■ THE PLAY BETWEEN COVES AND LITTORAL CAVES In Manacor harbour, the Genovesa cave is just over a hundred metres from the sea at the end of the Cala Anguila beach. The cove mouth measures 140 m in width, and it is 250 m in length (main polygonal axis of the cove) with an average width of 95 m. The cavity, a cave in the coastal mixing zone, runs 2,415 m and penetrates just over 500 inland, measuring © Grup Nord de Mallorca from the beach. Although a degree of protection is The Felanitx region (Mallorca) has a very rugged coastline, forming afforded by its classifi cation as an EU landmark of many bays and headlands, like Cala Sa Nau, which opens onto a community interest and as a site of cultural interest 100-metre gorge and Cala Mitjana. Yellow indicates the location of by the Council of Mallorca, wastewater from the the underwater cave in Cala sa Nau (1), the Ses Barraques cave (2), villegiatura pours directly into the cavity. This is a Cala Mitjana cave (3) and En Bassol cave (4). good example of how coastal fragility is facing the onslaught further inland and could reach of coastal urbanisation, not only «THE ONSLAUGHT OF almost another 50 metres. on the surface but also below Further south is Falcó cove, COASTAL URBANISATION ground with the pollution of 300 m wide and 175 m long. groundwater and –via drainage– NOT ONLY AFFECTS THE It presents several karstic- of the sea. SURFACE BUT ALSO BELOW marine captures of considerable The cave known as Cova del GROUND WITH POLLUTION importance, such as the Es Pilar, also on Manacor coast, OF GROUNDWATER AND –VIA Coloms cave in Falcó cove and is a cave of great beauty with the Cala Falcó cave, along with its grand entrance and large DRAINAGE– OF THE SEA» other associated cavities. The columns or pillars, covered with Cala Falcó cave is believed to be blue seaweed stirred up by the related to the well-known Pirata- waves during bad weather, visible from ships sailing Pont-Piqueta underground system, measuring 3,091 along the coast. It is a good example of karstic-marine m in length, which less than 200 m away and runs capture with large speleothems that are eaten away 700 m inland. The subsidence of ancient galleries by erosion wrought by waves, and is a paradigmatic has separated this cave from the endokarstic system. example of the sea penetrating inland as the cavity Moreover, the encroachment of Es Coloms cave by recedes. At present, the sea inlet, besides the roof the sea has visibly shifted the line of cliffs inland, and of the cave, measures about 40 m, but the sea goes left layers of quaternary loamy sediments hanging on 98 Annual Review MÈTODE 2013 MONOGRAPH The Enchanted Cove the sea cliff, which cling to the walls of the huge sea Marina de Pont cave. Of all these, the Cala Varques inlet. In addition to the beautiful lakes, this cave is B cave is the largest, running 1,068 m and with a notable for the presence of marine sands at the bottom maximum depth below sea level of more than 30 m. of a large dry gallery. Its location, at the back of the beach, is an indication 1 Just a short distance away and heading south, still of how the cave and Varques cove might eventually within the Manacor region, we fi nd Cala Varques. The evolve in the event that the roof of the gallery, which mouth measures some 200 m is located at an altitude much in width, 320 in length and is below sea level, collapses. an average of 160 m wide. The In Felanitx harbour, the cave «COVA GRAN HAS RECEDED caves lining the cove shoreline known as Cova Gran, is a large and in direct or near contact MORE THAN 70 METRES FROM hollow cavity formed by marine Magnetic with the sea are: Cala Varques B THE COAST LINE, FORCING abrasion, which has retreated North cave, Cala Varques ACD or Es URBAN GROWTH PLANS TO BE over 70 m with respect to the Xuetes cave, Es Genet cave, Es CHANGED» coastline and whose entire roof ➞ Coloms cave in Cala Varques or is susceptible to collapsing and the Es Coloms II cave and the forming a recess measuring more than 120 m. This has forced the change of urban planning near the cave. Cala Sa Nau and Cala Mitjana are located between Portocolom and Cala Herrera, although closer to the latter, and about 5 km from the town of S’Horta. They are part of the Felanitx bay, lined by Neogene calcareous rock measuring up to 4 km wide. It is a very rugged area of coastline forming many bays and sharp headlands. Cala Sa Nau opens onto a 100-m gorge, measuring 500 m in length and with an average width of 55 m. An outstanding landmark in the area is the En Bassol cavern, located in the coastal mixing zone, lying in a NE-SW direction and measuring 1,491 m in length. It was found by chance during water prospection, and has no natural entrance. The abundance and beauty of the speleothems and the size of the galleries make it a major attraction.

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