Updated Saturday 20/09/2008 20:09 (CET ) OSHIMA TANA MADRID .-
A Franco-English team draws the first geological map of the mountain.
The mapping includes the first map of recent climate events in the area.
Undress the mountains and outline the silhouette of the rocks that form, it is not easy. And much less reconstruct climatic conditions around the mountains during the Quaternary, the immediate past, although geologic immediately began 2.5 million years ago. Therefore, French and English geologists have thought it of interest to provide the first map of the Pyrenees to include this data.
bare mountains, and a glance.
The first comprehensive geological map of the Pyrenees, just delivered from the hand of French and English geologists, who have managed to compile existing data to draw for the first time a comprehensive topographical view of the mountain. The cartography, drawn up by the Geological and Mining Institute of Spain (IGME) and the Centre for Geological and Mining Research of France (BRGM), was presented Saturday at the University of Pau (France).
"We want to be useful also for the fans, because The items displayed are easily identifiable, "he told elmundo.es Cecilio Quesada, chief of staff's technical support unit to the general direction of IGME and secretary of the National Committee of Geology. To make it easier for users unless experts, the map is plotted on a shaded digital elevation model, taken by a NASA satellite. Through the shadows is possible to identify the physical geography, topography. "Until now the problem was to make a single map," he added Quesada. "There was no topographic support for it. There was one from France, one from Spain, but there was no common element. "
actually are two maps.
The first radiograph the mountains, outlining the silhouette of the rocks that form them and describing their nature and their age. Some are young and old, from which date back to the end of the Precambrian, about 600 million years ago (the Earth is about 4,500 million years), long before they formed their own mountain range (in the Tertiary, about 60 million years), to the most recent being the moraines (deposits associated with glaciers), about 15,000 years ago. And there are all types: granites and shales at the top, limestone, sandstone, clays and conglomerates in marginal areas.
the Pyrenees during the Quaternary
The second play how were the Pyrenees during the Quaternary (specifically, until about 250,000 or 300,000 years), the mountain was covered of glaciers, which moved mostly during the Pleistocene to go back later in warmer periods, and re-expansion during the Little Ice Age, between the seventeenth and eighteenth centuries.
The second play how were the Pyrenees during the Quaternary (specifically, until about 250,000 or 300,000 years), the mountain was covered of glaciers, which moved mostly during the Pleistocene to go back later in warmer periods, and re-expansion during the Little Ice Age, between the seventeenth and eighteenth centuries.
weather episodes of the immediate past (just a flicker on a geological scale) are accompanied by some cultures of both our ancestors and the most characteristic fauna of that period. For example, the arrival of Homo sapiens 50,000 years ago coincides with the largest expansion of ice in the Pyrenees. The mapping information also reflects other paleontological data, as the presence of mammoth in the mountainous region to 13,000 years ago. The glaciers in the recent past was the one who set the current form of the Franco-chain, as glaciers, which expand and recede depending on weather conditions, act as river erosion and help to sculpt the mountains at times of thaw. Now, with warming Overall, the large majority of these glaciers has disappeared or is disappearing. Hence the interest to know how were the Pyrenees in the past, says Quesada. "The dimensions of the Pyrenean glaciers during the Pleistocene were similar to those of the largest glaciers in the present can be found in the Alps, ie several tens of kilometers. The modeling of the Pyrenees and responds to higher erosive work carried out by glaciers during the Pleistocene last glacial maximum, "explains Juan José González Trueba, Department of Geography, University of Cantabria and English glaciologist.
The map scale 1:400.000, has been carried out under the International Year of Planet Earth 2008 , dedicated to the Earth Sciences.
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