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Lherz Massif
Lherz Massif is an upper mantle peridotite body in the French Pyrenees. The mineral lherzolite Lherzolite is a type of ultramafic igneous rock. It is a coarse-grained rock consisting of 40 to 90% olivine along with significant orthopyroxene and lesser amounts of calcic chromium-rich clinopyroxene. Minor minerals include chromium and alu ... takes its name from this rock body. References Geology of France Ophiolites Pyrenees {{geology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Mantle Body
An upper mantle body is a geological region where upper mantle rocks (peridotite) outcrop on the surface of the Earth (including the ocean floor). Upper mantle outcrops include: * upper mantle made at constructive plate boundaries, but preserved in ophiolites, for example Isabela ophiolite in the Philippines * upper mantle above subduction zones, so called suprasubduction ophiolites (Example Troodos Ophiolite, Cyprus ) * upper mantle exposed by thinning of continental crust by extension to continental crust removal (Ligurian "Ophiolites" and conjugate margin of Iberia and Newfoundland) *upper mantle exposures on earth's surface above sea-water level in Oceans (whose ocean floor is covered with oceanic crust). Examples are Macquarie Island in Pacific and St. Peter and Paul island in Atlantic. *upper mantle exposures on earth's surface on the ocean floor. Examples is Gakkel Ridge The Gakkel Ridge (formerly known as the Nansen Cordillera and Arctic Mid-Ocean Ridge) is a mid-oce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrenees
The Pyrenees (; es, Pirineos ; french: Pyrénées ; ca, Pirineu ; eu, Pirinioak ; oc, Pirenèus ; an, Pirineus) is a mountain range straddling the border of France and Spain. It extends nearly from its union with the Cantabrian Mountains to Cap de Creus on the Mediterranean Sea, Mediterranean coast. It reaches a maximum altitude of at the peak of Aneto. For the most part, the main crest forms a divide between Spain and France, with the microstate of Andorra sandwiched in between. Historically, the Crown of Aragon and the Kingdom of Navarre extended on both sides of the mountain range. Etymology In Greek mythology, Pyrene (mythology), Pyrene is a princess who eponym, gave her name to the Pyrenees. The Greek historiography, Greek historian Herodotus says Pyrene is the name of a town in Celts, Celtic Europe. According to Silius Italicus, she was the virgin daughter of Bebryx, a king in Narbonensis, Mediterranean Gaul by whom the hero Hercules was given hospitality during his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lherzolite
Lherzolite is a type of ultramafic igneous rock. It is a coarse-grained rock consisting of 40 to 90% olivine along with significant orthopyroxene and lesser amounts of calcic chromium-rich clinopyroxene. Minor minerals include chromium and aluminium spinels and garnets. Plagioclase can occur in lherzolites and other peridotites that crystallize at relatively shallow depths (20 – 30 km). At greater depth plagioclase is unstable and is replaced by spinel. At approximately 90 km depth, pyrope garnet becomes the stable aluminous phase. Garnet lherzolite is a major constituent of the Earth's upper mantle (extending to ~300 km depth). Lherzolite is known from the lower ultramafic part of ophiolite complexes (although harzburgite is more common in this setting), from alpine-type peridotite massifs, from fracture zones adjacent to mid-oceanic ridges, and as xenoliths in kimberlite pipes and alkali basalts. Partial melting of spinel lherzolite is one of the primary sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of France
The regional geology of France is commonly divided into the Paris Basin, the Armorican Massif, the Massif Central, the Aquitaine Basin, the Pyrenees, the Alps, the Côte languedocienne, the Sillon rhodanien, the Massif des Vosges, the Massif Ardennais, the Alsace graben (Rhine graben) and Flanders Basin. Alpine orogen The regions Alsace, Franche-Comté, Rhône-Alpes and Provence-Alpes-Côte d'Azur are part of the Western Alps. Sediment from the Valais ocean crop out in the Versoyen unit. The basement of the Briançonnais microcontinent crop out at Gran Paradiso, Dora Maira, Ambine, Vanoise and Ruitor. The Briançonnais cover sequences crop out in the Zone Houillère. External massifs include the Belledonne massif, Mont Blanc massif, Pelvoux-Écrins massif and the Argentera massif. Sediments from the Piemont-Liguria Ocean crop out in Embrunais and Ubaye. The Jura mountains are part of the Helvetic nappes, that represent deposits from the European margin that were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiolites
An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle that has been uplifted and exposed above sea level and often emplaced onto continental crustal rocks. The Greek word ὄφις, ''ophis'' (''snake'') is found in the name of ophiolites, because of the superficial texture of some of them. Serpentinite especially evokes a snakeskin. The suffix ''lite'' from the Greek ''lithos'' means "stone". Some ophiolites have a green color. The origin of these rocks, present in many mountainous massifs, remained uncertain until the advent of plate tectonic theory. Their great significance relates to their occurrence within mountain belts such as the Alps and the Himalayas, where they document the existence of former ocean basins that have now been consumed by subduction. This insight was one of the founding pillars of plate tectonics, and ophiolites have always played a central role in plate tectonic theory and the interpretation of ancient mountain belts. Pse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
