Kyanitic eclogite (Late Cretaceous, 90-95 Ma; near Fost, Slovenska Bistrica Municipality, Slovenia) 6 : 無料・フリー素材/写真
Kyanitic eclogite (Late Cretaceous, 90-95 Ma; near Fost, Slovenska Bistrica Municipality, Slovenia) 6 / James St. John
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
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| 説明 | Kyanitic eclogite from the Cretaceous of Slovenia. (~8.0 centimeters across at its widest)Eclogite is an attractive, scarce, crystalline-textured, very high-grade metamorphic rock. It is dominated by green and red minerals. The red is pyrope or almandine garnet. The green is omphacite pyroxene. Eclogite appears to be moderately common in portions of the upper mantle, but it occurs in very few places at the Earth’s surface. They have the same chemistry as basalts and gabbros (= oceanic crustal rocks), but have different mineralogies. Eclogites form by very high grade metamorphism of oceanic crust at mantle depths along subduction zones. Uplift of eclogites back to the surface often involves some retrograde metamorphism and the formation of new minerals, resulting in retrograde eclogites.The eclogite seen here is from the Eastern Alps in Slovenia. It has a kyanite component. Kyanite is a bluish to bluish-gray aluminum silicate mineral - Al2SiO5. (See: www.flickr.com/photos/jsjgeology/albums/72157677871157642) The resulting rock is red and green and blue - a remarkable color combination. Click on the photo to zoom in to see the bluish kyanite.Age: eclogite-facies metamorphism in the early Late Cretaceous, ~90 to 95 MaLocality: unrecorded/undisclosed site near the town of Fošt, Pohorje Mountains, southeastern margin of the Eastern Alps, Slovenska Bistrica Municipality, northeastern Slovenia |
| 撮影日 | 2019-12-09 17:18:19 |
| 撮影者 | James St. John |
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