The proposed site includes two protected areas: the Provincial Reserves Llancanelo Lake and Payunia
The first has 90,000 ha. of protected reserve, of which 65,000 ha., have been declared a Ramsar site in 1996. It is one of the few areas in the country with a participatory management plan, developed jointly with the residents, and is unique in the world with volumetric limits (600 m high and 600 meters deep), and so the conservation takes into account both, the air and its underground water reservoirs.
The reserve occupies a large depression (endorheic basin) modeled by volcanic processes and is fed by groundwater seepage (Menuco, Cari-lauquen, Carapacho) and surface contributions coming from the Andes (Malargüe River). Its size varies according to season but generally the lagoon is 50 km long from north to south and about 10-12 km wide east-west with a depth less than the meter.
In its environment highlights the Cerro Carapacho an ancient volcano and two other volcanoes known as Trapal and Coral. The most prominent feature are the aquatic birds, highlighting the concentrations of flamingo austral that nest regularly in the area, and the big and small threatened parinas that nest occasionally. It also highlights more than 10 species of waterfowl anatidae such as black-necked swan and coscoroba. It is also migratory route for many species of plovers, sandpipers and terns.
The Payunia Reserve covers 192.000 ha and is reserve since 1982, in the future will be expanded to 450,000 ha using available public land and other private lands with owners arrangement. In this part the volcanic territory reaches its peak focusing in its greater variety of volcanic landforms and creating a stunning landscape.
As distinctive features stand out in the relief the Payún Matru volcano with a huge caldera of 8 km in diameter which includes a semi-permanent lake inside the volcano and the Payún Liso volcano with a crater 400 m in diameter and 90 m deep. In addition, there are steppes with very low coverage among which we highlight the black solupe, jarillas, pichanilla, melosa and grass as the tupe and flechillas. Its concentrations of more than 11,000 individuals of guanacos, are remarkable as the density and diversity of fauna with two species of fox, Patagonian piche, puma, grassland cat, wild and the Andean cat, and the chinchillón occupies the edges of the plateaus. Among reptiles, various kinds of lizards are able to be seen and is where have been detected totally exclusive species or endemic in the site.
The flora and fauna have adapted to the volcanic soil and arid climate.
Justification of Outstanding Universal Value
Payún Matru and Llancanelo Volcanic fields are situated in the south of Mendoza province in the La Payunia recently described by Martínez Carretero (2004). They form a continuous area, with exclusively volcanic landforms, framed on the west by the Andes.
The diversity of volcanic forms is unique in the world, because of the coexistence of efusive and explosive eruptions, uncommon scenario on our planet. Volcanoes show a striking scenic beauty of outstanding aesthetic importance. In Llancanelo Volcanic Field there are more than hundred monogenetic basaltic cones, responsible to have closed the drainage network of the Malargue river hydrological complex, generating the Llancanelo lake endoreic basin, wetland that provides an outstanding biodiversity for the region. Morover, the Payún Matru Volcanic Field is dominated by the occurrence of two giants volcanoes: Payun Matru, 3.350 masl and Payun Liso, 3.680 masl.
The beauty of this area is unique because of the major extensión of volcanic area, the wide variety of landforms and the contrast of its landscapes, from the wetlands of Llancanelo lake to the highlands moore of Payún Matru volcano. Thus, the diversity of environments for flora and fauna is remarkable ranging from lake habitat of flamingos in a depressed area to the domains of the condor in the high peaks.
The volcanic activity of selected Site occurred during the Pleistocene-Superior and the Holocene. Because of the extreme youth of last eruptions (less than 10.000 years) volcanoes, their lavas and ashes are slightly eroded, maintain the landscape as it existed when the violent eruptions occurred. The preservation of this landscape brings us back to the time when the intensity of volcanic activity changed the geographical scene.
The diversity of eruptive styles conditioned forms of volcanoes: monogenetic cones, decapitated volcanoes due by gigantic volcanic explosions, stratocones with edifices of more than 2000 meters, huge calderas, variable morphology of lavas, from tens of kilometers long and a few meters thick to very short and thicknesses of over 200 m, some totally glassy, of singular beauty. This variety of volcanic landforms occur in very few places in the world because in volcanic fields worldwide the volcanism is always dominated by a single style eruption, either effusive or explosive. That is why we consider the site selected as unique in the world.
Satements of authenticity and/or integrity
The nominated property to be included on the Tentative List, covers an area of 8,000 km2 (approximately), and has all the necessary elements to express its outstanding universal value, being the most representative area of the Llancanelo and Payún Matru volcanic fields, containing all the varieties of volcanic landforms in this large district of 36,000 km2 and being the only place where are concentrated the younger eruptions, of less than ten thousand years old.
From a volcanology point of view it can be found all varieties of products and types of eruptions, frequent in volcanic fields of our planet. The eruptive styles range from effusive eruptions, called Hawaiian, to the explosive or plinian and sub-plinian style. Intermediate eruptive styles like Strombolian and Vulcanian are also frequent in the nominated property. The rocks composition range from olivine basalts, which magmas rise quickly from generation zone in the base of the lithosphere, about 100 kilometers deep, to trachytes, from magma chambers located very near the surface, within 1and 5 kilometers deep.
Small monogenetic volcanic cones, resulting from Strombolian eruptive phases, alternate with large stratovolcanoes (like Payún Liso) and giant shield volcanoes, such as Payún Matru. The lava flows range from low viscosity, eg., basalt, a few meters thick, to the highly viscous, such as trachyte, with thickness of more than 200 m. Consequently given all varieties of lava flows, from coulées, blocky lava, pahoehoe (smooth surface) and aa (rough surface) (both terms of Hawaiian origin.) The volcanoes are aligned along fissures of several kilometers in length. There are also many volcanoes whose morphology is caused by powerful explosions, known as phreatomagmatic volcanism, where the magma rises to reach the surface and interact with groundwater or surface water, and as a result of the rapid heating occurs a huge explosion (volcanoes Carapacho, Malacara, located in the Llancanelo volcanic field).
As detailed earlier, the property it is emphasized proposed to be incorporated into the Tentative List, is of adequate size, which allows a complete representation of the characteristics and of the eruptive processes, thus guaranteeing the integrity of the nominated site. He already has two cores inside formed by the two provincial reserves located a short distance and with a high potential to join in the future as one large unit, in addition to other planned extensions that become even more important and effective. In addition they allow the development and seasonal movements of many species represented since the depression of the Llancanelo Lake to the highest peaks of Andean influence, including territories of several and unique species worldwide
The site is one of the world areas that presents minimal human activity and most of the volcanic area is well preserved even today. In some areas there are small flocks of goats belonging to the few people who live there (0.05 inhabitants per km2). In the Payún Matru volcano and surrounding areas there are no permanent rivers and water is a limiting factor, these features make it into an almost uninhabited region, and so the landscape, flora and fauna remain unchanged. Furthermore it is noteworthy that the Secretary of Environment through the Dirección de Recursos Naturales Renovables of Mendoza province permanent handles the area through the rangers, and in this case, are effective reservations with management plans, facilitating the integrated management of the whole proposed as World Heritage.
Comparison with other similar properties
The proposed site has a wide range of eruptive styles, ranging from the extreme effusive to the extreme explosive, which can not be compared with other volcanic sites on the list of World Heritage Sites of UNESCO.
A comparison of the salient features that distinguish Payún Matrú and Llancanelo Volcanic Field with other volcanic sites known worldwide.
a) Teide National Park is a volcanic district which includes a large stratovolcano and several minor volcanic centers, located in the Island of Tenerife (Canary Islands, Spain). It´s a World Heritage Site since July 28, 2007. The Teide stratocone, with a height of 3,718 m above sea level, is the largest volcano on this site. Its height is similar to those of Payún Matru and Payún Liso, the volcanic features of this site are dominated by the active volcano Mount Teide, as well as lava and pyroclastic products. The big difference is that the island of Tenerife is inhabited, however Llancanelo and Payunia have no anthropogenic modifications due to the sparse population that inhabits keeping a pristine state such in morphological and geological aspects as in those of an environmental nature.
b) The Hawaii Volcanoes National Park, located in the Hawaii Archipelago, is characterized by an effusive basaltic volcanism, with a great variety of pahoehoe and aa lavas, lava lakes and lava tunnels, covered by a dense vegetation, this situation does not occur in Llancanelo and Payunia where the volcanic forms are very clearly exposed enhancing the scenic beauty of the Site.
For all these reasons, we hold that the Site proposed is unique in the world in terms of volcanic diversity in the same area.