The Stavelot Massif is a
geological massif in the
Belgian Ardenne
The Ardennes (french: Ardenne ; nl, Ardennen ; german: Ardennen; wa, Årdene ; lb, Ardennen ), also known as the Ardennes Forest or Forest of Ardennes, is a region of extensive forests, rough terrain, rolling hills and ridges primarily in Be ...
(geologically a part of the
Rhenish Massif
The Rhenish Massif, Rhine Massif or Rhenish Uplands (german: Rheinisches Schiefergebirge, : 'Rhenish Slate Uplands') is a geologic massif in western Germany, eastern Belgium, Luxembourg and northeastern France. It is drained centrally, south to n ...
). 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 is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
.
The massif consists of early
Paleozoic
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon.
The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838
by combining the Greek words ''palaiós'' (, "old") and ' ...
(late
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...
and
Ordovician 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, causin ...
s, mostly
quartzite
Quartzite is a hard, non- foliated metamorphic rock which 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 tect ...
s and
phyllites. In other parts of the Ardennes they form a
basement
A basement or cellar is one or more floors of a building that are completely or partly below the ground floor. It generally is used as a utility space for a building, where such items as the furnace, water heater, breaker panel or fuse box, ...
which is covered by only slightly
metamorphosed late Paleozoic
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
s and
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates) ...
s, that only saw a low degree of
metamorphism
Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chem ...
. On the other hand, the early Paleozoic rocks were deformed and metamorphosed to a higher degree during the
Caledonian orogeny (about 450 million years ago).
Both the Caledonian
basement
A basement or cellar is one or more floors of a building that are completely or partly below the ground floor. It generally is used as a utility space for a building, where such items as the furnace, water heater, breaker panel or fuse box, ...
and the low grade cover rocks were
deformed again during the
Hercynian orogeny (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 mathematic ...
of deformation created a large northeast-southwest oriented
anticline
In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is the ...
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
Competence may refer to:
*Competence (geology), the resistance of a rock against deformation or plastic flow.
*Competence (human resources), a standardized requirement for an individual to properly perform a specific job
*Competence (law), the me ...
of the Caledonian basement rocks made them more resistant to
erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is distin ...
. The massif therefore forms a
plateau
In geology and physical geography, a plateau (; ; ), 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. Often one or more sides ha ...
in the
topography
Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms 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 (german: Hohes Venn; french: Hautes Fagnes; nl, Hoge Venen), which were declared a nature reserve in 1957, are an upland area, a plateau region in Liège Province, in the east of Belgium and adjoining parts of Germany, between the ...
and encompasses the highest summits of Belgium.
References
Ardennes
Geology of Belgium
Landforms of Liège Province
Stavelot
{{regional-geology-stub