Camp dels Ninots

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Coordinates: 41 ° 50 ′ 7 "  N , 2 ° 47 ′ 54"  E

Map: Spain
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Camp dels Ninots​
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Spain
Excavations at Camp dels Ninots

Camp dels Ninots ( Catalan for "Field of Puppets") is a former maar and today an important fossil deposit in northeastern Spain . Numerous complete skeletons of large mammals, but also of small vertebrates and plant remains have been discovered here that lived on the banks of a former lake in the mid- Pliocene 3.2 million years ago. Investigations have been taking place since 2003.

location

Camp dels Ninots is an old maar in northeast Spain and is located near the town of Caldes de Malavella , the nearest town is Girona in the Selva administrative unit . The entire area is part of the La Selva Depression , which is bounded by the Paleozoic rock massifs of the Catalan Coastal Mountains, which blocks the way to the Mediterranean coast in the south, about 18 km away . The name of the maar comes from the occurrence of opal minerals , which are reminiscent of small dolls in their shape. There are other maars in the area that belong to the Catalan volcanic complex. Volcanism began here around 15 million years ago and has been dormant since the beginning of the Holocene . However, the main period of activity was during the Pliocene and led to the formation of extensive olivine basalt flows . The volcanic eruptions were both explosive and effusive in nature.

Geological structure

The Maar Camp dels Ninots has an approximately oval shape and extends over 900 m in the north-south direction and 800 m in the east-west direction. It reaches a depth of at least 90 m, the floor being embedded in granite . In the upper part it shows an asymmetrical structure, since in the southern area the crater wall is formed by soft sand, in the north by hard granite. In the surface, the edges of the maar are formed from volcanic pyroclasts , the basin itself was originally filled with water. This lake expanded to 650 by 400 m and silted up over time. Today the depression is filled with clays and muds , which represent the sediment residue of the formerly water-filled maar. The relatively uniform filling of the maar suggests a unique eruptive event, in the course of which the depression was created. The upper areas are exposed to a depth of up to 8 m. Here the clays and mudden have a predominantly grayish-white or greenish color. In these layers of clay and mud there are isolated layers of sandstone . The geologists differentiate between a total of four deposit units, of which unit 2 (counting from the bottom) is most clearly pronounced with a thickness of over 5 m. This in turn is divided into four sub-units. Fossil finds were found scattered throughout the layer package, from the deposit unit 3, which can be assigned to the Pleistocene , some tools made of flint , which refer to the presence of early humans at the Maar Camp dels Ninots. However, the important fossils and complete skeletons were discovered in the third section of Unit 2, which is around 2.5 to 3.5 m below today's surface and consists predominantly of greenish-gray clays overlaid by a sandstone block.

Finds

All finds are characterized by excellent preservation, showing no signs of weathering . Large mammals generally appear as articulated skeletons and lie in a sideways position. Since they show no signs of gnawing or eating by small mammals or predators , they must have sunk into the water very quickly and become too sedimented . Changes to the skeleton were largely due to tectonic processes in the sense of the formation of cracks and sediment slippage during the settlement process of the deposits.

flora

Large plant debris includes imprints of leaves , trapped twigs, and pips . The leaves mostly come from the laurel family , but also from the oak and Daphnogene polymorpha , the pips are mostly from the alder . In addition, remains of spruce , pine , fir , birch , cypress and hazelnut have come down to us. Other plants are heather , strawberry trees , heather or mugwort represented. Also, fungi and protists were found.

fauna

So far, the remains of the animals include freshwater fish, amphibians, reptiles and mammals and are of exceptional conservation quality. Notably, no mollusc shells were found, which is relatively unusual for sea debris. This may be related to special abiotic processes during sediment formation. Water in volcanic maars is often acidic to slightly basic, which leads to the dissolution of calcite , the main component of the mussel and snail shells, and to the precipitation of silicates .

Among the mammals has been so far to the Horn carriers belonging Alephis tigneresi was detected most frequently, complete with three skeletons. This species is related to Parabos and is possibly close to today's Nilgau antelope . With a suspected body weight of around 500 kg, it is the largest bovid in Europe that does not belong to the actual cattle . Furthermore, the tapir Tapirus arvernensis was excavated with several complete skeletons, including four full-grown and nearly full-grown individuals and a newborn baby first complete this kind. this medium Tapirvertreter connected to the Malayan tapir is closely related, is a typical European faunal of the Miocene and Pliocene and has worked with Camp dels Ninots be southernmost occurrence on this continent. Stephanorhinus jeanvireti , which is closely related to the Sumatran rhinoceros , is another odd ungulate , a large representative of this rhino genus, possibly weighing up to 3 t. Here, too, there is an almost complete skeleton, which is only missing the front legs because of a sediment disturbance. So far only the wood mouse relative Apodemus atavus has been found in small mammals .

The birds have so far been occupied with ducks of the genus Aythya and with cormorants , and also with pheasant-like species . The finds consist largely of only remnants of wing and leg bones. Among the reptiles, two complete skeletons of the Spanish water turtle ( Mauremys leprosa ) are to be mentioned, the shell of which is between 12 and 25 cm long. The remains of the shell of Chelydropsis , an extinct representative of the alligator turtles , can be seen as unusual . They are among the youngest and most western European finds. Amphibians include tailed amphibians and frogs . The tail amphibians are represented by the large genus Pleurodeles and the small form Lissotriton . Individual bones are available from both genera, and from Lissotriton there is also a complete skeleton about 6 cm long. The frog Pelophylax , on the other hand, is proven by four well-preserved skeletons. The fish have only been partially examined, but at least three cyprinid forms have been identified, including the genera Barbus and Leuciscus .

Age position

The horn-bearer Alephis tigneresi and the rhinoceros Stephanorhinus jeanvireti are particularly important for dating . The bovid occurs mainly in the early Pliocene , later it is replaced by Leptobos . Camp dels Ninots belongs to the last appearance of this horned species. Stephanorhinus jeanvireti, on the other hand, appears here for the first time and replaces the more primitive Stephanorhinus megarhinus . According to this, the deposits leading to the found should belong to the transition period of the units MN 15 to MN 16 determined by mammalian stratigraphy and, according to today's standards, should be around 3.2 million years old. All other fossils are so far less informative.

Paleomagnetic investigations on the deposits of Camp dels Ninots revealed a change in the orientation of the ferromagnetic minerals from normal (as today) to reverse (reverse) polarization , which took place with the reversal of the earth's magnetic field and the associated change from the north to the south. This happened several times in the history of the earth. Due to the presumed age of the deposits, two possibilities are possible from a magnetostratigraphic point of view, on the one hand the Kaena event (3.04 to 3.11 million years) or the Mammoth event (3.22 to 3.33 million years) during the Gauss - Era, each of which showed a brief reversal from the predominantly normally polarized state at that time to a reverse.

Landscape reconstruction

Based on the plant remains, an evergreen subtropical forest with a high proportion of laurel plants can be reconstructed, which was inhabited by herbivores adapted to soft plant food such as Tapirus arvernensis and Stephanorhinus jeanvireti . Today's tapirs prefer a humid climate with only minor seasonal fluctuations. Since tapirs are generally a very conservative group of mammals that have only undergone few changes in their tribal history , such a climate adaptation is also assumed by the fossil representatives. The presence of the bovid Alephis tigneresi also suggests a certain proportion of open landscapes, but the species was not a highly specialized herbivore because of its teeth. The tailed amphibian Pleurodeles indicates that the maar lake must have been quite deep. These views are confirmed by pollen analyzes on the maar deposits, according to which there was a very diverse flora, which was composed of subtropical, Mediterranean and temperate plants. The vegetation existed under relatively humid, subtropical conditions. However, in the course of the 200,000 years that passed before the Maarsee was filled, the climate dried up significantly.

research

The first investigations in Camp dels Ninots took place in 1882 by Lluís M. Vidal, whose focus was on the origin of the sediments. In the period that followed, there was little work, but the first fossil of an extinct horned bear was described in the mid-1980s . More intensive investigations began in 1999 after members of the Asociación Arqueológica de Gerona had made the first discoveries made of flint. From 2003 interdisciplinary research on archeology and palaeontology began under the leadership of the Institut Català de Paleoecologia Humana i Evolució Social of the Universitat Rovira i Virgili of Tarragona , with annual excavation campaigns. The researchers penetrate to a depth of 5 m.

literature

  • Gómesz de Soler, Campeny Vall-Llosera, Jan van der Made, O. Oms, J. Augustí, R. Sala, H.-A. Blain, F. Burjachs, J. Claude, S. García Catalán, D. Riba, R. Rosillo: A new key locality for the Pliocene vertebrate record of Europe: the Camp dels Ninots maar (NE Spain). In: Geologica Acta 10 (2), 2012, pp. 1-17.
  • Gerard Campeny Vall-Llosera, Bruno Gómez de Soler, Jordi Agustí, Robert Sala, Oriol Oms, Jan van der Made, Francesc Burjachs, Gonzalo Jiménez, Hugues-Alexandre Blain, Julien Claude, Tomáš Pˇrikryl, Isabel Expósito, Juan José Villalaín, Ángel Carrancho, Eduardo Barrón, Souhila Roubach, Lucía López-Polín, Xavier Bolós, Gala Gómez Merino, Núria Ibáñez, Lluís García, Pablo Mateos, David Riba, Rafel Rosillo, Alfonso Díaz i Sergio García: El Camp dels Ninots (Caldes de Malavella, la Selva): balanç de deu anys d'intervencions arqueopaleontològiques. In: Tribuna d'Arqueologia , 2012/2013, pp. 141-163 ( [1] ).

Individual evidence

  1. ↑ a b c d e f g h i j Gómesz de Soler, Campeny Vall-Llosera, Jan van der Made, O. Oms, J. Augustí, R. Sala, H.-A. Blain, F. Burjachs, J. Claude, S. García Catalán, D. Riba and R. Rosillo: A new key locality for the Pliocene vertebrate record of Europe: the Camp dels Ninots maar (NE Spain). In: Geologica Acta 10 (2), 2012, pp. 1-17.
  2. ↑ Gala Gómez-Merino, Nuria Ibáñez, Gerard Campeny and Bruno Gómez de Soler: Actuaciones de conservación-restauración y almacenaje de un cráneo de bóvido del yacimiento paleontológico del Camp dels Ninots (Caldes de Malavella)., In: C. Cancelo Fernández, S. Val Molina, J. Marigó Cortés and L. Celià Gelabert (Eds.): I Consevation Workshop: Finding Global Solutions for Natural History Collections. Sabadell, Servei de Publicacions de la Universitat Autònoma de Barcelona. In: Memòria especial 4, 2009, pp. 201–202.
  3. ↑ O. Oms, X. Bolós, S. Barde-Cabusson, J. Martí, A. Casas, R. Lovera, M. Himi, B. Gómez de Soler, G. Campeny Vall-Llosera, D. Pedrazzi and J. Agustí: Structure of the Pliocene Camp dels Ninots maar-diatreme (Catalan Volcanic Zone, NE Spain). In: Bulletin of Vulcanology 77, 2015, p. 98.
  4. ↑ Esteban Meseguer-Despons, Bruno Gómez de Soler, Gerard Campeny, Jordi Augustí and Joan Madurell Malapeira: Early Villafranchian tapirs from the Camp dels Ninots Maar (La Selva Basin, NE Iberian Peninsula). In: Bienvenido Martínez-Navarro, Paul Palmqvist, M. Patrocinio Espigares and Sergio Ros-Montoya (eds.): Libro de Resúmenes de las XXXV Jornadas de Paleontología. Sociedad Española de Paleontología, Baza, 2 - 5 de octubre 2019. Baza, 2019, pp. 193–196.
  5. ↑ a b IPHES: Camp dels Ninots. ( online ), El Camp dels Ninots, la Pompeia del pliocè. ( PDF ), Institut Català Paleontologia Humana i Evolucié Social.
  6. ↑ Gerard Campeny Vall-Llosera, Bruno Gómez de Soler, Jordi Agustí, Robert Sala, Oriol Oms, Jan van der Made, Francesc Burjachs, Gonzalo Jiménez, Hugues-Alexandre Blain, Julien Claude, Tomáš Pˇrikryl, Isabel Expósito, Juan José Villalaín, Ángel Carrancho, Eduardo Barrón, Souhila Roubach, Lucía López-Polín, Xavier Bolós, Gala Gómez Merino, Núria Ibáñez, Lluís García, Pablo Mateos, David Riba, Rafel Rosillo, Alfonso Díaz and Sergio García: El Camp dels de Malavella (Caldes , la Selva): balanç de deu anys d'intervencions arqueopaleontològiques. In: Tribuna d'Arqueologia , 2012/2013, pp. 141-163.
  7. ↑ Tomáš Přikryl, Bruno Gómez de Soler, Gerard Campeny, Oriol Oms, Souhila Roubach, Hugues-Alexandre Blain and Jordi Agustí: Fish fauna of the Camp dels Ninots locality (Pliocene; Caldes de Malavella, province of Girona, Spain) - first results with notes on palaeoecology and taphonomy. In: Histiorical Biology 26, 2014, doi: 10.1080 / 08912963.2014.934820 .
  8. ↑ Ángel Carrancho Alonso, Juan José Villalaín, Bruno Gómez de Soler, Gerard Campeny Vall-llosera, Manuel Calvo-Rathert, Oriol Oms, Jan van der Made and Jordi Agustí: Estudio Magnetostratigrafico en dos Sondeos del Maar del Camp dels Ninots, Caldes de Malavella (Girona, NE-España). In: Latinmag Letters 1, 2011, pp. 1-5.
  9. ↑ Gonzalo Jiménez-Moreno, Francesc Burjachs, Isabel Expósito, Oriol Oms, Ángel Carrancho, Juan José Villalaín, Jordi Agustí, Gerard Campeny, Bruno Gómez de Soler and Jan van der Made: Late Pliocene vegetation and orbital-scale climate changes from the western Mediterranean area. In: Global and Planetary Change 108, 2013, pp. 15–28.