Escuain Valley
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Geo route ESCUAIN PN1010 VALLEY TELLA, REVILLA & ESCUAIN c Sobrarbe Geopark Texts: The Geo-Routes PN are taken from the Geological Guide Ordesa and Monte Perdido National Park" from the Collection of Geological guides of the National Parks (IGME-OAPN, Roberto Rodríguez Fernández, dir and coord.) The texts of these Geo-routes have been developed by Alejandro Robador Moreno, Luis Carcavilla Urquí, Josep Maria Samsó Escolá and Ánchel Belmonte Ribas (Scientific Coordinator Sobrarbe Geopark). Figures and illustrations, by Albert Martinez Ríus, and photographs by Josep María Samsó Escolá, Luis Carcavilla Urquí, Alejandro Robador Moreno and Ángel Salazar Rincón Translation into French and English: Trades Services, S.L. Design and layout: Pirinei, S.C. CBC project Pyrenees-Monte Perdido, World Heritage (PMPPM) GEO- of the 2007-2013 POCTEFA Program. ROUTE NETWORK OBRARBE GEOPARK GEO-ROUTE S NETWORK The Sobrarbe Geopark is located in the north of the province of Huesca and coincides with the district of the same name. This area is noted for its many cultural and natural values, most notably its spectacular geology. j` Indeed, the Geo-Route network of the Sobrarbe Geopark was created to learn about and Taken together, these routes will enable visitors to enjoy the most beautiful parts of the Sobrarbe district and also obtain further information on its long geological history dating back over 500 million years. THE SOBRARBE GEOPARK In 2006 the Sobrarbe District was declared a Geopark and became part of the European Geopark Network, sponsored by UNESCO. A Geopark is a district with unique geological features for which a sustainable development strategy has been developed. Consequently, the key objective is to preserve its natural and cultural heritage and promote development through the appropriate management of the geological environment. There are currently 60 Geoparks in Europe and 100 in the word. The Sobrarbe Geopark features an exceptional geological environment, with over 100 places of geological interest that have been inventoried; many of which can be visited on the Geo-Route network. More info: www. geoparquepirineos.com 1 AP OF THE SOBRARBE GEOPARK M GEO-ROUTE NETWORK Gèdre Aragnouet Gavarnie Bujaruelo Pineta Monte Viadós Perdido Río Cinca A-138 Bielsa PARQUE Víu Torla P.N. DE ORDESA Y NATURAL MONTE PERDIDO DE Broto POSETS- Escuaín MALADETA Fanlo Gistaín San Juan de Plan Ara Saravillo Nerín Plan Río Puértolas Lafortunada Fiscal Laspuña N-260 Ascaso Escalona Labuerda San San Juan de Toledo Boltaña Victorián Foradada Aínsa N-260 Campo Las Bellostas Embalse de Tierrantona Mediano PARQUE NATURAL Arcusa DE LA SIERRA Y Palo LOS CAÑONES DE Paúles Samitier GUARA de Sarsa Río Esera Bárcabo Abizanda Lecina Embalse de A-138 El Grado GEO 1 Geo-Route PN 1 Geo-Route in National Park of Ordesa and Monte Perdido The various Sobrarbe geo-routes vary in length, difficulty, theme and duration. Consequently, almost everyone will be able to find a route that suites them. 2 Nº GEO-ROUTE TRAVEL DIFFICULTY DURATION THEME* 1 Geopark Interpretation Centre Geopark area - 1 hour All Aínsa: a town between two rivers. 2 Urban geology Aínsa Low Short R T F Samitier castle and 3 Low Medium TF Geology: A bird's eye view hermitages 4 Inside the canyon Congosto de Entremón Medium Short TR Vero River canyon 5 Breath-taking landscapes of water Low Medium RF and rock viewpoints 6 Sobrarbe at your feet Ascaso- Nabaín Medium Medium TF 7 Crossing the Jánovas Gully Near Jánovas Medium Short TR 8 Iron Age Elements Viu-Fragén-Broto Low Short GR Medium- 9 Long Whims of water for lonely mountaineers Ordiso Valley High GKR A lake among the oldest rocks in 10 Sobrarbe Lake Pinara and Puerto Viejo Low Medium GR 11 The hidden lake Lake Bernatuara Medium Long RGT 12 A road with tradition Bujaruelo Pass Medium Medium RGT Fiscal-Gradatiello- High 13 A privileged vantagepoint Peña Canciás Long RT 14 Secrets of the Guara Mountains Las Bellostas-Sta. Marina Low Long FRT Low 15 Geology for the Saint Espelunga de San Victorián Short RT 16 A passage between two worlds Collado del Santo Medium Long RFT Low 17 Water inside the Earth Badaín-Chorro de Fornos Medium KR Basa de la Mora Low 18 The Jewel of Cotiella (Ibón de Plan) Short GR 19 Treasures of the Posets-Maladeta Viadós-Ibones de Millars Medium Long GR Nature Park GEO-ROUTE IN NATIONAL PARK OF ORDESA AND Nº MONTE PERDIDO TRAVEL DIFFICULTY DURATION THEME* Torla-Cola de Caballo- Low- RGF PN1 Ordesa Valley Góriz Shelter Medium** Medium Góriz Shelter-Mount Perdido PN2 Mount Perdido High Long TRKGF PN3 The Roland Gap Góriz Shelter - Roland Gap High Long TRKGF PN4 Cutas Viewpoints Torla-Viewpoints-Nerín Low** Medium KRGFT Low** PN5 La Larri Bielsa-La Larri Valley Medium RGT High PN6 Balcon de Pineta Pineta-Balcón de Pineta Long FTG Medium PN7 Añisclo Canyon (lower part) San Urbez-Fuen Blanca Long RGT PN8 Añisclo Canyon (upper part) Fuen Blanca-Añisclo Pass High Long RGTF Escalona-Puyarruego PN9 Circuit Añisclo Canyon Low** Medium RTK Tella, Revilla-Escuaín PN10 Escuaín Valley Low** Medium TK Broto -Bujaruelo- PN11 Otal Valley Otal Valley Low** Medium GTK * Theme: T- Tectonics; F- Fossils;K- Karst; R- Rocks; E- Stratigraphy; G- Glaciarism ** Combining vehicle and hiking 3 GEOLOGICAL HISTORY OF THE SOBRARBE GEOPARK The geological history of the Sobrarbe Geopark goes back over 500 million years. Many geological events that have affected the current landscape and relief took place over that vast period of time. The geological history of Sobrarbe can be divided into 6 different episodes, each of which includes significant moments that led to today's geological landscape. THE REMOTEST PAST 1 (between 500 and 250 million years ago) Over a long period of the Palaeozoic, the land now occupied by Sobrarbe was a seabed where silt, mud, clay and sand accumulated. Today these sediments have become the shale, sandstone, limestone and quartzite that form the northern mountains and valleys of the District. These rocks were intensely altered by the Variscan orogeny: an episode of intense tectonic activity that affected much of Europe and resulted in a huge mountain range. Numerous folds and faults attest to this past together with granite that was also formed in that era. Folds in Palaeozoic rocks TROPICAL MARINE SEDIMENTATION 2 (between 250 and 50 million years ago) The giant mountain range formed in the previous stage was heavily eroded and almost disappeared. Once erosion has almost swept away the mountain range, the resulting flat land was covered by a shallow tropical sea. Coral reefs appeared and the calcareous mud we see today in the shape of limestone, dolomite and marl, containing abundant marine fossils, accumulated. The sea fluctuated several times and there were many time when its depth increased and decreased; however, it practically covered the area throughout this episode. Fossils of marine organisms in the Cretaceous limestone THE FORMATION OF THE PYRENEES 3 (between 50 and 40 million years ago) The marine sedimentation process continued during this episode, but under very different conditions to previous episodes. The sea, which separated what is today the Iberian Peninsula from the rest of Europe, gradually dried up. About 45 million years ago, as this sea became narrower and sedimentation occurred on the seabed, thousands of Typical landscape of turbidites outcrops metres below the surface, on land, the Pyrenees began to develop. I In Sobrarbe we can find exceptional examples of turbidites, rocks formed in that sea as it accumulated huge amounts of sediments resulting from the development of the mountain range, while the mountains continued to develop. PALAEOZOIC 542 m.a. 488 m.a. 443 m.a. 416 m.a. 359 m.a. 299 m.a. 251 m.a. 199 m.a. 145 m.a. 65 m.a. 23 m.a. 2,5 m.a. Cambrian Ordovician Silurian Devonian Carboniferous Permian Tria Jurassic Cretaceous Palaeogene Neogene Quaternary EPISODES: 1 4 SOBRARBE GEOPARK THE SOBRARBE DELTAS (between 40 and 25 million years ago) 4 The formation of the mountain range caused the gradual disappearance of the sea, which was becoming shallower and elongated. About 40 million years ago, a system of deltas marked the transition between the area that had emerged and later stages of this marine gulf. Although this period was relatively short, huge amounts of sediment accumulated, which can be found today in the southern part of the District converted into marl, limestone and sandstone. Once the sea had retreated definitely from Sobrarbe, the relentless effects of erosion became all the more intense if possible. About 25 million years ago, active and dynamic torrents accumulated huge amounts of gravel that, over time, became conglomerates, such as those that form the bulk of Conglomerates: rocks formed from rounded Peña Canciás. fragments of other rocks THE ICE AGES 5 (last 2,5 million years) Once the mountain range and its foothills had formed, erosion began to transform it. The river valleys widened and the present river network began to be formed. On several occasions during the Quaternary, mainly over the last two and a half million years, various cold spells occurred, covering the mountains with snow and ice. The last major ice age reached its peak about 65,000 years ago. Huge glaciers covered the valleys and mountains and shaped the landscape, effectively eroding some places and accumulating sediment in others. The landscape of the entire northern section of the District was shaped by those ancient glaciers. Glaciers like the ones we see today in the Alps covered the Pyrenees at that time 6 TODAY Today, erosion processes are slowly and gradually wearing away the mountain range. This erosion occurs in many ways: through the action of rivers, erosion on the slopes, karst dissolution, etc.