Europe geology
Europe's plate tectonic growth began in the
Precambrian and was far advanced when Europe and
Asia for approximately 300 million years ago by
collision in the Uralids was united into one large
continent, Eurasia. The plate movements in the
Precambrian and Paleozoic were for several periods
faster than today, and Europe was led from one
active plate boundary to another. During its
operation, Europe annexed several island arcs and
microcontinents and collided several times with
large continents; it resulted in repeated mountain
chain folds. When Europe seceded, it sometimes left
parts of its continental crust with the collision
partner, but in the long run, the continent grew to
the west and south.
A distinction is made between a pre-Cambrian core
area (Baltic Shields and the Eastern European
Platform), the Caledonian and Varisian growth belts
in Western and Central Europe, and the Cimmerian and
Alpine belts in SE and Southern Europe. Large parts
of Europe are covered by younger sediments deposited
on stable platforms or in subsidence basins and
burial depressions. Tertiary volcanic rocks form
scattered deposits on the continent and the British
Isles; The Faroe Islands and Iceland are made up of
plateau basalt. In Iceland, which lies on the
mid-Atlantic ridge, volcanism continued.
Mediterranean volcanoes are particularly associated
with young plate boundaries and active subduction
zones.
Precambrian Europe (3500-550 million years). The
continental crust in NE Europe consists of 3500-800
million years old bedrock rocks mainly formed and
collected during archaic and early Proto-Zero
mountain range folds within 1600 million years
before now. For approximately 1000 million years
ago, when the Sveconorvegian mountain range was
formed, the area collided with the continent
Laurentia (North America-Greenland) and became part
of a very large Proterozoic continent, which for
700-550 million years ago was broken up again. While
Europe drifted towards the South Pole, during the
Cadomic mountain range folding, an elongated folding
belt and arch system developed at an active plate
boundary off Eastern Europe, the so-called Pre-Uralids,
which build the Timan Mountains and form part of the
Ural Mountains.
Paleozoic Europe (550-250 million years). At the
break-up, Europe left large parts of its
pre-Cambrian crust in the southern hemisphere. The
rest, Baltica, formed the germ of contemporary
Europe. During the subsequent Caledonian mountain
range folds (approximately 500-400 million before
now), changing plate movements led small and large
areas of new and old continental crust to collision
with Baltica. When the microcontinent Avalonia
reached from the south, the Avalonean Caledonids
were folded up. Most of this folding belt is now
deeply buried under younger sediments, in northern
Germany and the southernmost part of Denmark. The
Caledonians in Scotland, Norway and Sweden
originated when Laurentia from the northwest
collided with Avalonia and Baltica. Before the
Caledonian folds were completed, new plates with
continental fragments and young island arcs were on
their way from the south; it heralded the varicose (hercynic)
mountain range folds that culminated in late Devon
to early Carboniferous when Gondwanathe continent
collided with Europe. This created an up to 1000 km
wide growth belt in southwestern, central and
central Europe. The meandering course of the
mountain ranges is due to the fact that two large
peninsulas in Gondwana and several microcontinents,
Armorica, was pushed into Europe. The intense
shooting caused relatively light crust to form deep
"roots" beneath the young mountains. When the
compression ceased, the folding chain rose so fast
that the mountains became unstable and "sank
together" along sliding planes. Transformations in
the depths gradually made the roots so heavy that
they broke off and sank into the asthenosphere,
while hot material from here and alkaline magma rose
up and spread out under the remaining, thinner
crust. The heat supply resulted in the melting of
many granites. As Europe late in Carbon lay close to
the equator, A sinking foreland basin was developed,
where in addition to sand and clay, plant material
was deposited from surrounding tropical swamp
forests. The coal deposits in the British Isles, in
Belgium, the Ruhr area and Śląsk (formerly Silesia)
arose from later heat conversion of these layers.
The dilapidated, varicose fold mountains are now
exposed in separate masses, The Armorican Massif,
the Central Massif and the Bohemian Massif. When
Europe collided with Asia late in Carbon to early
Permian, lively fault activity prevailed southwest
of Baltica; several fracture zones developed in
NW-SE and NS-going directions, and alkaline-acid to
alkaline magmas penetrated. This formed The Oslo
Rift, the Fennoscandian Border Zone and the fault
systems that, in later revival, led to the
development of the Tornquist zone between the North
Sea and the Black Sea. Early in Perm, two wide
east-west basins were formed, which were partly
separated by a barrier from northern England to
Ringkøbing-Fyn Højderyggen. When the Zechstein Sea
from the north penetrated and filled the basins,
these were located at approximately 20 °, and
desert-like climate caused such a strong evaporation
that several series of evaporites with thick layers
of rock salt precipitated. This so-called Zechstein
salt was buried during the Mesozoic and Tertiary
under kilometer-thick sediments and thereby flowed
together in cushion structures. Where the salt
penetrated the overlying layers, it rose up into
elongated salt ridges and like round salt thrushes.
Several oil and gas deposits in the North Sea, the
Norwegian Sea and the Barents Sea are linked to
these salt structures.
Young Europe (the last 250 million years). At the
beginning of the Mesozoic, Europe was part of the
supercontinent Pangea, but during the Triassic Jura,
Eurasia split from Africa, and at the opening of the
Atlantic Ocean, Europe was later also separated from
North America-Greenland. While this was going on,
two new crust growth belts were added to Europe's
active plate boundaries to the south and east; first
the cimmeric, then the alpine. The Cimmerian Growth
Belt from the Triassic-Old Cretaceous encompasses
the mountain ranges around the Black Sea. West of
this, a number of contiguous scattering oceans, the
so-called Mediterranean Tethys Sea, were opened in
the Jurassic-Early Cretaceous.. This sea was closed
again when Africa and the microcontinent Adria in
the Late Cretaceous-Tertiary collided with Europe.
This created the southern alpine mountain ranges of
southern Europe, The Betic Cordilleras, the
Pyrenees, the Alps and the Carpathians. At the end
of the period, decomposition materials from the
growing mountains were deposited as molasses in
sinking basins.
In the Paleogene and early in the Quaternary, the
processes in the depths below the alpine collision
belt remained active. In the western Mediterranean,
the rise of hot material from the asthenosphere led
to approximately 24-19 million years ago for local
seabed dispersal and opening of the Provencal
Ligurian Sea. Thereby, an elongated microplate with
Corsica and Sardinia, which lay close to the south
of France and northeastern Spain, was driven
counterclockwise and rotated 40-90 °Counterclockwise
to its current position closer to Italy. As the
subduction zone east of Corsica and Sardinia shifted
its slope so that it reached below the Apennines,
Tuscany's young volcanic province was formed; at the
same time, the upper plate was raised, causing young
sediment covers in the Apennines to slide towards
the sinking Adriatic below the Posletten and the
Adriatic Sea. The Tyrrhenian Sea was opened for
approximately 5-2 million years ago north of the
arcuate Calabrian-Sicilian folding belt, which has
developed in the upper plate over a subduction zone
where the African ocean floor plate from the Ionian
Sea has sunk into Sicily and southern Italy. The
eruptions of the volcanoes of the Aeolian Islands
testify to the magmatic processes in the deep parts
of this zone. The interplay of the deep processes
further caused the neogene Mediterranean to become
constricted, so that by evaporation thick layers of
salt precipitated. The alpine folding belts of
southeastern Greece, Crete, Rhodes and Cyprus now
belong, like the Taurus Mountains in Turkey, to the
seismically highly active Anatolian microplate,
which is being liberated from the Eurasian. At the
depths of the sea south of Crete and Cyprus, the
African ocean floor is slowly moving north and down
below the microplate, but the pressure from the
faster Arab plate in the east forces the Anatolian
to rotate counterclockwise. It causes displacements
in the curved fault zone in northern Turkey and
stretching of the crust under the Aegean Sea.
The alpine collisions propagated far north under
Western Europe. This led to the formation of the
Rhône, Bresse and Rhing graves and increased
subsidence in the Central Grave and the Viking Grave
in the North Sea. Worn-out massifs were transformed
into quarry mountains, and in the sediment basins
elongated ridges arose, along Tornquist zones. At
the same time, the Mesozoic layers on SV-Bornholm
were "alpine" folded.
During the Quaternary ice ages, large parts of
northern Europe as well as the Alps were several
times covered by ice caps and glaciers, which at the
time of the melting left a cover of moraine and
meltwater deposits. In front of the rim of the
northern European ice cap, the finest material,
clay, silt and fine sand, was deposited by the wind
as loess. South of the icy and loosely covered
areas, strongly reddish soils have been preserved in
many places, which were formed by weathering during
the warmer climate of the Tertiary period.
Europe's ore deposits
Europe has a very traditional mining industry
with numerous, early known ore deposits, such as
mining of tin in Cornwall in the Bronze Age, silver
in Kongsberg under Christian IV and copper in
southern Germany and in Cyprus. The vast majority of
the deposits are now depleted, which has created
major social problems in communities that have lived
off mining for generations. Known examples are the
closure of coal mines in the UK and Germany.
Deposits of iron ore and coal in Britain, Lorraine
and western Germany were important preconditions for
the breakthrough of industrialization in the 1800's.
Mineral deposits associated with granitic rocks
are known, among other things. from Cornwall, the
Harz Mountains, the Ore Mountains, France, the
Iberian Peninsula and from the North, from which
tungsten, molybdenum, cobalt and tin were previously
mined. Today, only a few granitic uranium deposits
are mined in France. Copper, lead, zinc and barium
deposits associated with volcanic rocks are mined in
the Nordic countries, Cyprus and the Iberian
Peninsula. Lead and zinc from sedimentary carbonate
rocks are mined in Ireland and the Alps, and copper
is mined from black shales in Poland. BIF (banded
iron ores), sedimentary manganese deposits and
uranium-containing shales are exploited in the
Iberian Peninsula, the Nordic countries, Russia and
Ukraine. Magmatic deposits with chromium, nickel and
copper are mined in the Balkans and in the Nordic
countries, Russia and Cyprus. Phosphorineral apatite
is mined from magmatic deposits in Finland and
Russia. In recent years, Europe has become
gold-producing from small deposits in The Nordic
countries, France, Spain and Eastern Europe.
Source:
https://www.countryaah.com/european-countries/ |