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The result is a distinct boundary of very fine grain igneous rock along the border of the country rock. [3] The surrounding rock may be "baked" through contact metamorphism, resulting in non-foliated metamorphic rocks. [1] Rocks that were originally limestone, quartz sandstone, and shale become marble, quartzite, and hornfels, respectively.
In geology, texture or rock microstructure [1] refers to the relationship between the materials of which a rock is composed. [2] The broadest textural classes are crystalline (in which the components are intergrown and interlocking crystals), fragmental (in which there is an accumulation of fragments by some physical process), aphanitic (in which crystals are not visible to the unaided eye ...
In geology, a bed is a layer of sediment, sedimentary rock, or volcanic rock "bounded above and below by more or less well-defined bedding surfaces". [1] A bedding surface is three-dimensional surface , planar or curved, that visibly separates each successive bed (of the same or different lithology ) from the preceding or following bed.
At one time it was ascribed to the presence of thin scales of mica which were believed to permit a certain amount of motion between adjacent grains of quartz. More probably, however, it is due to the porous character of the rock together with the interlocking junctions between the individual quartz sand grains. The porosity allows interstitial ...
For example, sedimentary rocks may be interbedded if there were sea level variations in their sedimentary depositional environment. [ 2 ] Intercalation is a special case of interbedding where a layer is variably inserted into an already existing sequence; or where two separate depositional environments in close spatial proximity migrate ...
The Giant's Causeway (Irish: Clochán an Aifir) [1] is an area of approximately 40,000 interlocking basalt columns, the result of an ancient volcanic fissure eruption. [3] [4] It is located in County Antrim on the north coast of Northern Ireland, about three miles (4.8 km) northeast of the town of Bushmills.
The voids between the facing stones are carefully packed with smaller stones (filling, hearting). Construction work on dry stone. Illustration of the Valencian Museum of Ethnology. The final layer on the top of the wall also consists of large stones, called capstones, coping stones or copes. As with the tie stones, the capstones span the entire ...
Metamorphic rocks are formed by subjecting any rock type—sedimentary rock, igneous rock or another older metamorphic rock—to different temperature and pressure conditions than those in which the original rock was formed. This process is called metamorphism, meaning to "change in form". The result is a profound change in physical properties ...