Geology of Belgium

Last updated

The geology of Belgium encompasses rocks, minerals and tectonic events stretching back more than 500 million years. Belgium covers an area of about 30,507 square kilometers and was instrumental in the development of geology. The extensive outcrops in Belgium became the standard reference points in stratigraphy as early as the mid-19th century. Some of them are internationally recognized features related to the Carboniferous and the Devonian periods. These rocks were folded by two mountain building events: the Hercynian orogeny and Caledonian Orogeny. Paleozoic basement rocks cover much of the country and are overlain by Mesozoic and Cenozoic sediments. [1]

Contents

Physiography

Belgium is divided into three physiographic sections (lower, middle, and upper Belgium) extending from east to west. The middle part is composed Paleozoic rocks that are partially covered by Cenozoic sediments; while the upper part is made up of chains of rock related to the Caledonian orogeny and Hercynian orogeny. If the post-Paleozoic rock cover were to be removed from the basement complex, several other major rock groups would be exposed:

After the erosion of the Hercynian chain, there was a continuous intrusion of the basement rock by younger rocks and crustal warping. The evidence of Triassic and Permian sequences are visible in some of the boreholes in the Campine Belt, due to preservation by block faulting. The Jurassic outcrops found in the south-east of Ardennes are made up of littoral sandy facies of the Gaume (French Jurassic basin). In the Pays de Herve and Haine Gulf there are Cretaceous rocks found mainly in the gentle trough along the Condroz Fault.

Stratigraphy and Sedimentation

Paleozoic

The stratigraphic column includes a series of repeated subsidence events, interrupted by diastrophism, with occasional uplifts, volcanism, and flysch sedimentation. The only exception to this is pattern are Cambrian and Silurian sediments. During the Devonian period, deposition left sediments that increase in thickness from north to south. The location of the continental masses was in the northern part of Belgium up to the Carboniferous period. Troughs were connected to basins in what is now France and parts of the Paleozoic period are absent from the stratigraphic column due to erosion, particularly in Brabant and the Ardennes. Early Devonian rocks are miogeosynclinal, while the middle and the upper Devonian preserve unstable basin and shelf sequences. Abraded continental blocks did not supply much of the detrital sedimentary material; with the exception of Famennian rocks. Arenite formed in these rocks as a result of early Hercynian orogeny tectonic activity.

The Dinantian carbonate shelf was preceded by sedimentation with infrequent marine incursions, and numerous coal seams. This sedimentation was later interrupted in the latter part of the Westphalian by the thrusting of the Ardennes and Dinant Synclinorium. [2]

Mesozoic and Cenozoic

The Mesozoic is usually characterized by the stability and the peneplanation of the basement rock. The Germanic continental facies mark the Triassic, and a series of marine transgression events took place during the Albian, Maastrichtian, Hettangian and Bajocian. This peneplane was invaded from the northwest repeatedly by shallow seas in the Cenozoic period. This transgression rarely crossed the Condroz Fault system that acted as a hinge between the slightly elevated Dinant Synclinorium and the downwarped crust in northern Belgium.

Since the Quaternary was a period of extreme weather events, most of the geologic features (such as terraces and valleys) in Belgium developed during that time. For example, the Ardennes upland was mostly subjected to severe weathering related to glaciation. During the Holocene, and Flandrian, sections developed that were characterized by fluctuations in sea level that resulted in dunes and thin peat deposits. [3]

Economic geology

Due to the presence of the Westphalian coal deposits, the industrial revolution in Belgium paralleled that of England. The coal from the mines was used in the industries to produce steam. The main industries that were supported by coal include steel, cement, and glass industries. Most of these industries are found along the Hercynian axis. However, since the 1990s, the coal industry in Belgium has been depressed due to the unstable coal mines (caused by complicated tectonic movements) and struggled to compete with those in neighboring Germany and France. Steady production of coal, even from modern mines in Campine on the northern flank of the Brabant Massif, decreased from 30 million tons between 1930 and 1950 to about 10 million tons in 1970—a drop of about 20 million tonnes in a span of 20 years.

In Belgium, there are also quarries that produce Marbre Noir de Dinant, Red Frasnian Marble, and Bleu Belge, although most of them have closed due to the depletion of the mineral deposits. These marbles were exported to other parts of Europe as decorative and building stones as early as the Roman period. Operational mines produced three million tons of ornamental stone in the late 1990s. In the Hercynian rocks are hydrothermal veins and metasomatic replacements in carbonates there exist other mineral deposits such as fluorite, barite, sphalerite, galena pyrite, and smithsonite. However other mineral deposits were largely exhausted by the beginning of the 20th century.

Oil prospection has not been successful in Belgium due to the deformation and metamorphosis of the Paleozoic rocks. [4]

Related Research Articles

<span class="mw-page-title-main">Rhenohercynian Zone</span> Fold belt of west and central Europe, formed during the Hercynian orogeny

The Rhenohercynian Zone or Rheno-Hercynian zone in structural geology describes a fold belt of west and central Europe, formed during the Hercynian orogeny. The zone consists of folded and thrust Devonian and early Carboniferous sedimentary rocks that were deposited in a back-arc basin along the southern margin of the then existing paleocontinent Laurussia.

The geology of Malawi formed on extremely ancient crystalline basement rock, which was metamorphosed and intruded by igneous rocks during several orogeny mountain building events in the past one billion years. The rocks of the Karoo Supergroup and newer sedimentary units deposited across much of Malawi in the last 251 million years, in connection with a large rift basin on the supercontinent Gondwana and the more recent rifting that has created the East African Rift, which holds Lake Malawi. The country has extensive mineral reserves, many of them poorly understood or not exploited, including coal, vermiculite, rare earth elements and bauxite.

The geology of Niger comprises very ancient igneous and metamorphic crystalline basement rocks in the west, more than 2.2 billion years old formed in the late Archean and Proterozoic eons of the Precambrian. The Volta Basin, Air Massif and the Iullemeden Basin began to form in the Neoproterozoic and Paleozoic, along with numerous ring complexes, as the region experienced events such as glaciation and the Pan-African orogeny. Today, Niger has extensive mineral resources due to complex mineralization and laterite weathering including uranium, molybdenum, iron, coal, silver, nickel, cobalt and other resources.

The geology of Morocco formed beginning up to two billion years ago, in the Paleoproterozoic and potentially even earlier. It was affected by the Pan-African orogeny, although the later Hercynian orogeny produced fewer changes and left the Maseta Domain, a large area of remnant Paleozoic massifs. During the Paleozoic, extensive sedimentary deposits preserved marine fossils. Throughout the Mesozoic, the rifting apart of Pangaea to form the Atlantic Ocean created basins and fault blocks, which were blanketed in terrestrial and marine sediments—particularly as a major marine transgression flooded much of the region. In the Cenozoic, a microcontinent covered in sedimentary rocks from the Triassic and Cretaceous collided with northern Morocco, forming the Rif region. Morocco has extensive phosphate and salt reserves, as well as resources such as lead, zinc, copper and silver.

The geology of Estonia is the study of rocks, minerals, water, landforms and geologic history in Estonia. The crust is part of the East European Craton and formed beginning in the Paleoproterozoic nearly two billion years ago. Shallow marine environments predominated in Estonia, producing extensive natural resources from organic matter such as oil shale and phosphorite. The Mesozoic and much of the Cenozoic are not well-preserved in the rock record, although the glaciations during the Pleistocene buried deep valleys in sediment, rechanneled streams and left a landscape of extensive lakes and peat bogs.

The geology of Georgia is the study of rocks, minerals, water, landforms and geologic history in Georgia. The country is dominated by the Caucasus Mountains at the junction of the Eurasian Plate and the Afro-Arabian Plate, and rock units from the Mesozoic and Cenozoic are particularly prevalent. For much of its geologic history, until the uplift of the Caucasus, Georgia was submerged by marine transgression events. Geologic research for 150 years by Georgian and Russian geologists has shed significant light on the region and since the 1970s has been augmented with the understanding of plate tectonics.

The geology of Ukraine is the regional study of rocks, minerals, tectonics, natural resources and groundwater in Ukraine. The oldest rocks in the region are part of the Ukrainian Shield and formed more than 2.5 billion years ago in the Archean eon of the Precambrian. Extensive tectonic evolution and numerous orogeny mountain-building events fractured the crust into numerous block, horsts, grabens and depressions. Ukraine was intermittently flooded as the crust downwarped during much of the Paleozoic, Mesozoic and early Cenozoic, before the formation of the Alps and Carpathian Mountains defined much of its current topography and tectonics. Ukraine was impacted by the Pleistocene glaciations within the last several hundred thousand years. The country has numerous metal deposits as well as minerals, building stone and high-quality industrial sands.

<span class="mw-page-title-main">Geology of Moldova</span>

The geology of Moldova encompasses basement rocks from the Archean and Paleoproterozoic dating back more than 2.5 billion years, overlain by thick sequences of Neoproterozoic, Paleozoic, Mesozoic and Cenozoic sedimentary rocks.

<span class="mw-page-title-main">Geology of Luxembourg</span>

The geology of Luxembourg is divided into two geologic regions: Rheinisches Schiefergeblige in the north, extending into the Ardennes region in Belgium, and the Oesling Zone to the north of Ettelbruck. The country is underlain by the Hercynian orogeny related Givonne Anticlinorium, which mainly contains Early Devonian sandstone and shale. Rocks closer to the surface are primarily from the Cretaceous and are cut by the Sauer River and its tributaries.

The geology of Bhutan is less well studied than many countries in Asia, together with the broader Eastern Himalayas region. Older Paleozoic and Precambrian rocks often appear mixed together with younger sediments due to the Himalayan orogeny.

<span class="mw-page-title-main">Geology of New York (state)</span> Overview of the geology of the U.S. state of New York

The geology of the State of New York is made up of ancient Precambrian crystalline basement rock, forming the Adirondack Mountains and the bedrock of much of the state. These rocks experienced numerous deformations during mountain building events and much of the region was flooded by shallow seas depositing thick sequences of sedimentary rock during the Paleozoic. Fewer rocks have deposited since the Mesozoic as several kilometers of rock have eroded into the continental shelf and Atlantic coastal plain, although volcanic and sedimentary rocks in the Newark Basin are a prominent fossil-bearing feature near New York City from the Mesozoic rifting of the supercontinent Pangea.

The geology of Laos includes poorly defined oldest rocks. Marine conditions persisted for much of the Paleozoic and parts of the Mesozoic, followed by periods of uplift and erosion. The country has extensive salt, gypsum and potash, but very little hydrocarbons and limited base metals.

<span class="mw-page-title-main">Geology of South Korea</span>

The geology of South Korea includes rocks dating to the Archean and two large massifs of metamorphic rock as the crystalline basement, overlain by thick sedimentary sequences, younger metamorphic rocks and volcanic deposits. Despite the country's small size, its geology is diverse, containing rocks formed during the Precambrian to Cenozoic eras.

<span class="mw-page-title-main">Geology of Kyrgyzstan</span>

The geology of Kyrgyzstan began to form during the Proterozoic. The country has experienced long-running uplift events, forming the Tian Shan mountains and large, sediment filled basins.

The geology of Turkmenistan includes two different geological provinces: the Karakum, or South Turan Platform, and the Alpine Orogen.

<span class="mw-page-title-main">Geology of Bulgaria</span>

The geology of Bulgaria consists of two major structural features. The Rhodope Massif in southern Bulgaria is made up of Archean, Proterozoic and Cambrian rocks and is a sub-province of the Thracian-Anatolian polymetallic province. It has dropped down, faulted basins filled with Cenozoic sediments and volcanic rocks. The Moesian Platform to the north extends into Romania and has Paleozoic rocks covered by rocks from the Mesozoic, typically buried by thick Danube River valley Quaternary sediments. In places, the Moesian Platform has small oil and gas fields. Bulgaria is a country in southeastern Europe. It is bordered by Romania to the north, Serbia and North Macedonia to the west, Greece and Turkey to the south, and the Black Sea to the east.

<span class="mw-page-title-main">Geology of Slovakia</span> Overview of the geology of Slovakia

The geology of Slovakia is structurally complex, with a highly varied array of mountain ranges and belts largely formed during the Paleozoic, Mesozoic and Cenozoic eras.

The geology of Greece is highly structurally complex due to its position at the junction between the European and African tectonic plates.

<span class="mw-page-title-main">Geology of the Czech Republic</span>

The geology of the Czech Republic is very tectonically complex, split between the Western Carpathian Mountains and the Bohemian Massif.

The geology of Denmark includes 12 kilometers of unmetamorphosed sediments lying atop the Precambrian Fennoscandian Shield, the Norwegian-Scottish Caledonides and buried North German-Polish Caledonides. The stable Fennoscandian Shield formed from 1.45 billion years ago to 850 million years ago in the Proterozoic. The Fennoscandian Border Zone is a large fault, bounding the deep basement rock of the Danish Basin—a trough between the Border Zone and the Ringkobing-Fyn High. The Sorgenfrei-Tornquist Zone is a fault-bounded area displaying Cretaceous-Cenozoic inversion.

References

  1. ↑ Moores, E.M.; Fairbridge, Rhodes W. (1997). Encyclopedia of European & Asian Regional Geology. Springer. pp. 79–81.
  2. ↑ Moores & Fairbridge 1997, p. 80.
  3. ↑ Moores & Fairbridge 1997, pp. 80–81.
  4. ↑ Moores & Fairbridge 1997, p. 81.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.