The Stavelot Massif is a
geological massif in the
Belgian Ardenne
The Ardennes ( ; ; ; ; ), also known as the Ardennes Forest or Forest of Ardennes, is a region of extensive forests, rough terrain, rolling hills and ridges primarily in Belgium and Luxembourg, extending into Germany and France.
Geological ...
(geologically a part of the
Rhenish Massif
The Rhenish Massif, Rhine Massif or Rhenish Uplands (, : 'Rhenish Slate Uplands') is a geologic massif in western Germany, eastern Belgium, Luxembourg and northeastern France. It is drained centrally, south to north by the river Rhine and a few ...
). Most of the massif crops out in Belgium, but a small part lies across the border with
Germany
Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...
.
The massif consists of early
Paleozoic
The Paleozoic ( , , ; or Palaeozoic) Era is the first of three Era (geology), geological eras of the Phanerozoic Eon. Beginning 538.8 million years ago (Ma), it succeeds the Neoproterozoic (the last era of the Proterozoic Eon) and ends 251.9 Ma a ...
(late
Cambrian
The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...
and
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...
in age)
metamorphic rock
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock ( protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, caus ...
s, mostly
quartzite
Quartzite is a hard, non- foliated metamorphic rock that was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tecton ...
s and
phyllite
Phyllite ( ) is a type of foliation (geology), foliated metamorphic rock formed from slate that is further metamorphosed so that very fine grained white mica achieves a preferred orientation.Stephen Marshak ''Essentials of Geology'', 3rd ed. I ...
s. In other parts of the Ardennes, they form a
basement
A basement is any Storey, floor of a building that is not above the grade plane. Especially in residential buildings, it often is used as a utility space for a building, where such items as the Furnace (house heating), furnace, water heating, ...
which is covered by only slightly
metamorphosed
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causi ...
late Paleozoic
limestone
Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...
s and
sandstone
Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...
s, that only saw a low degree of
metamorphism
Metamorphism is the transformation of existing Rock (geology), rock (the protolith) to rock with a different mineral composition or Texture (geology), texture. Metamorphism takes place at temperatures in excess of , and often also at elevated ...
. On the other hand, the early Paleozoic rocks were deformed and metamorphosed to a higher degree during the
Caledonian orogeny
The Caledonian orogeny was a mountain-building cycle recorded in the northern parts of the British Isles, the Scandinavian Caledonides, Svalbard, eastern Greenland and parts of north-central Europe. The Caledonian orogeny encompasses events tha ...
(about 450 million years ago).
Both the Caledonian
basement
A basement is any Storey, floor of a building that is not above the grade plane. Especially in residential buildings, it often is used as a utility space for a building, where such items as the Furnace (house heating), furnace, water heating, ...
and the low-grade cover rocks were
deformed again during the
Hercynian orogeny
The Variscan orogeny, or Hercynian orogeny, was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea.
Nomenclature
The name ''Variscan ...
(about 350-280 million years ago). This
phase
Phase or phases may refer to:
Science
*State of matter, or phase, one of the distinct forms in which matter can exist
*Phase (matter), a region of space throughout which all physical properties are essentially uniform
*Phase space, a mathematica ...
of deformation created a large northeast-southwest-oriented
anticline
In structural geology, an anticline is a type of Fold (geology), fold that is an arch-like shape and has its oldest Bed (geology), beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex curve, c ...
that runs across the Belgian part of the Rhenish Massif (the Ardennes anticline). In the core of this anticline a number of massifs of early Paleozoic rocks crop out. The Stavelot Massif is one of the larger, other Caledonian massifs are the Rocroi Massif, the Serpont Massif , and the Givonne Massif.
The higher
competence
Broad concept article:
*Competence (polyseme), capacity or ability to perform effectively
Competence or competency may also refer to:
*Competence (human resources), ability of a person to do a job properly
**Competence-based management, performa ...
of the Caledonian basement rocks made them more resistant to
erosion
Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, tran ...
. The massif therefore forms a
plateau
In geology and physical geography, a plateau (; ; : plateaus or plateaux), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. ...
in the
topography
Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the landforms and features themselves, or a description or depiction in maps.
Topography is a field of geoscience and planetary sci ...
. This plateau is called the
High Fens
The High Fens (; ; ), which were declared a Nature reserve, nature reserve in 1957, are an upland area, a Plateau, plateau region in Liège Province, in the east of Belgium and adjoining parts of northwestern Germany, between the Ardennes and the ...
and encompasses the highest summits of Belgium.
References
Ardennes
Geology of Belgium
Landforms of Liège Province
Stavelot
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