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 Harzer Urgesteine - Torfhaus, Germany
N 51° 48.165 E 010° 32.239
32U E 605998 N 5740217
A display of the three primary rock types of the Harz Mountains
Waymark Code: WMPYQP
Location: Niedersachsen, Germany
Date Posted: 11/12/2015
Views: 52
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The Harz Mountains are the highest mountain range in North Germany. At its base there are three kind of rock, Granite, Diabase and Gabbro.
This display is at the Visitor's Center of Harz National Park, located in the German state of Niedersachsen.
In 2000, the EXPO World Fair was held in Niedersachsen's capital Hannover, and as part of the EXPO, the monument Harz Primary Rock was erected. |
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Our pictures were taken at at foggy, rainy day. You can see a better picture at the site of the
Earth Cache at this location.
The earth cash is loaded with information. We borrowed the descriptions of the rock formations from that site.
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Granite is a common and widely occurring type of intrusive, felsic, igneous rock with usually a medium- to coarse-grained texture. They can be pink to gray in color, depending on their chemistry and mineralogy. By definition, granite is an igneous rock with at least 20% quartz by volume. Outcrops of granite tend to form tors and rounded massifs. Granites sometimes occur in circular depressions surrounded by a range of hills, formed by the metamorphic aureole or hornfels.
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Diabase or dolerite is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. In North American usage, the term diabase refers to the fresh rock, whilst elsewhere the term dolerite is used for the fresh rock and diabase refers to altered material. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine grained to aphanitic chilled margins which may contain tachylite (dark mafic glass). Diabase has a characteristic greenish color.
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Gabbro is a compact, coarse-graine rock of plutonic origin. It was formed deep under the Earth's surface when molten magma was trapped beneath the Earth's surface and cools into a crystalline mass. The color of gabbro is grey-black, sometimes blue-green, due to the high proportion of dark minerals like pyroxen and olivin which are teh main component of this rock.
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Type of Display: Geological
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Visit Instructions:
When posting a visit, please provide at least one photo - including yourself in one of of the photos, your GPSr, or a photo different than the default photo.
Also, please provide your impression of the specimen or display.
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