Sunday, 15 July 2018

Football Rocks: World Cup Geology Tour...by Kirstin Lemon

The World Cup final day is finally here. It’s been a fantastic month of football with lots of surprises and of course, it’s also been a fantastic month of discovering a little bit about the geology of all 32 participating countries. In case you missed and of our World Cup Geology Tour we’ve put them all together in one handy blog.

Argentina: Argentina is famous around the world for its giant dinosaur fossils. These aren't just any old giant dinosaurs, these were the biggest dinosaurs to have ever lived! Discovered in 2013, fossils of Patagotitan mayorum, an extra-large titanosaur that lived during the Late Cretaceous period (100 million years ago) were found by a farmer in the Chubut Province. Over 200 bones have now been uncovered and these have been pieced together to get a true picture of what this dinosaur would have looked like, and we now know that it would have been 70m in length and 15m high.

Australia: We couldn't resist choosing one if its most famous, albeit predictable, geological icons, Uluru. At 3.6km long and 2.4km wide, this 348m high geological feature is made up of red/brown feldspathic sandstone. It is often described as a 'monolith' that literally means 'one stone' and can often be slightly ambiguos. Geologists much prefer to use the term 'inselberg' which is used to describe a prominent, isolated steep-sided residual upland surrounded by extensive flat plains. Uluru is part of the Uluru-Kata Tjuta National Park World Heritage Site, inscribed on the World Heritage List for both its cultural and geological significance.

Han-sur-Lesse caves, Belgium
Belgium: We've chosen the Lomme karst area located, near the city of Rochefort in the south of Belgium. The karst is located in a series of Middle Devonian limestones and is a major groundwater resource. The limestones display extensive cave development. Many of these have been developed as show caves included those at Han-sur-Lesse, a major Belgian tourist attraction. The Lomme karst area is located within the Famenne-Ardenne UNESCO Global Geopark, Belgium's first and only geopark.

Brazil: We’ve chosen the Paraná Plateau (or Paraná traps) a large igneous province that would have formed as flood basalts during the Early Cretaceous associated with rifting that would ultimately form the South Atlantic Ocean. The Paraná Plateau lies mostly in the states of Rio Grande do Sul and São Paulo in Brazil, it also appears in Uruguay, Argentina and Paraguay. A severed extension of the plateau is found in northwest Namibia and southwest Angola where it is known as the Etendeka traps. In Brazil where the Paraná Plateau is exposed at the surface it weathers to produce a fertile dark purple soil known as terra roxa that is famous as producing excellent coffee.

Costa Rica: Costa Rica is arguably best known for its volcanoes and in total there are nearly 70 active or extinct ones. Arenal is one of the best-known and most-visited volcanoes. It is located in the volcanic arc of Costa Rica that results from the subduction of the Cocos plate under the Caribbean plate.

Colombia:  One of the best known ‘geology’ tourist attractions is the Zipaquirá salt cathedral located in a disused salt mine in the town of Zipaquirá, 48km from Bogotá. The cathedral was carved by miners and sculptors in the mines out of the 70 million year old salt deposits found in the middle of the eastern Andean mountain range.

'Istrian stone', Croatia
Croatia: This time we’re not visiting a site but a building stone, specifically Istrian stone, or pietra d'Istria. This building stone is characteristic of the architecture of Dalmatia and perhaps more well-known as being used to build the foundations of Venice which had no building stone nearby. The limestone was quarried in Istria, between Portorož and Pula and is sometimes mistaken for marble which is actually metamorphosed limestone.

Denmark: The location this time is the Odsherred Peninsula, an iconic site for glacial geology in Northern Europe. Groundbreaking scientific research has been ongoing in the area since the early part of the 20th century when Odsherred’s hills were interpreted as being end moraines as opposed to eskers. This ‘new’ explanation was initially dismissed but since then, although more complex than initially thought, the glacial landforms are now accepted as being end moraines formed as a result of colliding ice streams that reached the fringes of the West Baltic Basin.

Egypt: Famous for its iconic pyramids, not many people really ever think about what they're actually made of. Many are constructed from Eocene limestone from the Giza Plateau. The limestone is known for its high content of Nummulites, a type of foraminifera, often used as a valuable index fossil. They can range in size from around 1cm in diameter to 5cm. The word 'Nummulite' is derived from the Latin word nummulus meaning 'little coin', with the ancient Egyptians actually using the shells for this purpose!

The White Cliffs of Dover, England
England: Out of all the amazing geological sites that we could have chosen we've gone for the White Cliffs of Dover which, together with Beachy Head and The Needles have welcomed many sea-faring travellers to southern England over the centuries. But there is more to the Cretaceous of southern Britain than magnificent chalk headlands for a wide variety of sandstones and mudstones occur in the Lower Cretaceous. It is these alternating hard and soft strata that weather into the hills and vales that perhaps epitomise the English landscape made famous by artists such as John Constable, Thomas Gainsborough and JS Cotman. Inland the chalk forms the rolling countryside of much of Dorset, the Hampshire Downs, Salisbury Plain, Marlborough Downs, the North and South Downs, the Chilterns and their north-eastwards continuation through Cambridgeshire and East Anglia. It underlies the Lincolnshire and Yorkshire wolds, and at Flamborough Head the chalk is carved into sea stacks, arches and wave-cut platforms.

France: With a country this size it was hard to choose one location but we’ve gone for the Rochechouart crater. Although the original crater morphology has disappeared this impact crater is part of the Réserve Naturelle Nationale de l’astroblème de Rochechouart-Chassenon because of its significant geological heritage value. The age of the Rochechouart impact is still the subject of debate but it is thought to have occurred between 207 and 203 million years ago. Although the morphology of the impact crater can’t be seen, certain features are seen that are characteristic of this type of event including a rock called suevite (seen below). This unusual rock is a type of breccia made up of shocked and unshocked rock fragments together with partly melted material.

The Eyes of the Eifel, Germany
Germany: We’ve chosen Eifel highlands in the northwestern part of the ‘Rheinish Slate Mountains’. This area is famous for its volcanoes, with 350 known eruption centres. There were two volcanic phases: the first was active between 45 to 35 Ma; the second was around 1 Ma and ended with the most recent eruption 10900 years ago. This area is the international type locality of maar craters, broad, low-relief volcanic craters caused by eruptions that occurs when groundwater comes into contact with hot lava or magma. In some craters, bogs and lakes have formed, while others remain dry. This landscape is sometimes referred to as ‘The Eyes of Eifel’ and is one of the main features of the Vulkaneifel UNESCO Global Geopark.

Iceland: This was a tough choice as there are so many fantastic locations to choose from. Situated on the Mid-Atlantic Ridge, Iceland is located at the tectonic plate boundary between the North American plate and the Eurasian plate, something that probably every single secondary school pupil is taught as part of their geography lessons, albeit in an oversimplified way. For that reason we've gone for the 'Bridge Between Continents' located on the Reykjanes peninsula and not that far from Iceland's main airport at Keflavik. It is also part of the Reykjanes UNESCO Global Geopark. However, it should be pointed out that the rift between the two tectonic plates is actually a zone of sub-parallel fissure swarms, often tens of kilometres wide and not as straightforward as North America on one side and Europe on the other.

Iran: The southern part of Iran is known for its numerous salt domes, many of which have been eroded into fine salt karst landscapes as well as containing the world's longest and largest salt caves. One such cave is located in Qeshm Island, in the Persian Gulf, where the 6.5km long Namakdan salt caves are thought to be the longest. There are numerous salt karst features associated with the cave including a salt spring resurgence where the stream channel is floored with crystalline salt.

Mount Fuji (or Fujisan), Japan
Japan: One of its most famous landmarks is undoubtedly Mount Fuji, the highest mountain in Japan at 3776m. Fuji is also a large composite stratavolcano that consists of alternating lava flows and pyroclastics. It is actually composed of three cones; Komitake, Older Fuji and Younger Fuji, put in order of decreasing age. Mount Fuji (or Fujisan) was inscribed on the World Heritage List in 2013 but as a site of cultural heritage significance and not because of its geological heritage.

South Korea: The Jeju Volcanic Island and Lava Tubes is a World Heritage Site and a UNESCO Global Geopark. Its central feature is Hallasan, the tallest mountain in South Korea and also a volcano. In addition to this feature there are 360 satellite volcanoes. But what the area is perhaps best known for is its extensive network of lava tubes. These are natural conduits through which lava travels beneath the surface of a lava flow. The tubes form by the crusting over of lava channels.

Mexico: We’ve chosen the Yucatán Peninsula and its karst landscape, particularly the features that are referred to 'cenotes'. Derived from the Yucatec-Mayan word 'ts'onot', it was a term used to describe any location with accessible groundwater. Cenotes are a type of sinkhole and formed by dissolution of rock (typically limestone) and the resulting subsurface void, which may or may not be linked to an active cave system. They are commonly found in low latitude areas, typically on islands and coastlines with post-Palaeozoic limestone. In the Yucatán Peninsula of Mexico, cenotes were sometimes used by the ancient Maya for sacrificial offerings.

Atlas Mountains, Morocco
Morocco: Mount Toubkal in Morocco is the highest peak in the Atlas Mountains, that stretch for 2500 km through Morocco, Algeria and Tunisia. The Atlas Mountains are divided into a number of subranges and formed as a result of several phases of tectonic activity that began during the Palaeozoic era and ended during the Neogene period.

Panama: For this one we're not focusing on a particular site but an event. In this case it's the formation of the Isthmus of Panama believed to be one of the most important geological events to happen on Earth in the last 60 million years. The Isthmus of Panama is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North and South America. But even though it is only a tiny sliver of land, its formation 2.8 million years ago as the Cocos plate slid under the Caribbean plate, had a huge impact on our climate and environment as it shut down the flow of water between the Atlantic and Pacific Oceans.

Peru: We've chosen Vinicunca, or the Rainbow Mountain located in the Peruvian Andes. It gets its name from the mineral rich layers of Permian sedimentary rocks that have weathered to give the vivid colours of ochre, red, yellow, and sometimes even turquoise.

Poland: Salt deposits are making another appearance on our tour and this time its the turn of the Wieliczka Salt Mine located in the town of Wieliczka within the Kraków metropolitan area. The mines were opened in the 13th century, and produced table salt continuously until 2007. The salt deposits formed during the Miocene period and stretch for about 10km beneath Wieliczka, with the salt being between 500 and 1500m thick. The salt mines have now been developed as a tourist attraction are have been inscribed on the UNESCO World Heritage List since 1978.

'Giant' trilobite, Portugal
Portugal: We’ve chosen Arouca UNESCO Global Geopark, famous for, amongst other things, fossils of 'giant' trilobites. Often found in large quarrying surfaces of roofing slates, this otherwise waste material has yielded several of the world's largest trilobite specimens, with some reaching up to 70cm.

Russia: Russia is home to Mount Elbrus, the highest peak in Europe. It has two peaks, one of which is 5642m and the other is 5621, both of which are volcanic domes. Mount Elbrus formed more than 2.5 million years ago and its last eruption took place about AD 50. The area also contains numerous hotsprings.

Saudi Arabia: We've chosen Mada'in Saleh an archaeological site located in the the Al Madinah Region.. The fabulous rock-cut architecture dates back to the 1st century and is characteristic of the Nabatean kingdom which also included Petra, in modern day Jordan. The settlement is carved out of the Ordovician Quweira sandstone, perfect for creating monuments and sculptures.
Serbia: We're off to the Djerdap National Park and more specifically the Djerdap Gorge, also known as The Iron Gate and is one of the longest river gorges in Europe. This complex river gorge comprises four smaller ones: Gornja Klisura, Gospodjin Vir, Kazan and Sipska Klisura and is over 100 km long.

Senegal: We’ve gone for the Senogambian stone circles found in Senegal and Gambia. These monuments are found at four large sites are believed to have been constructed between the third century BC and the sixteenth century. The stone circles consist of upright blocks or pillars made mostly of laterite a rock that is rich in iron and aluminium and formed due to intense weathering, such as that common in hot and wet tropical climates, of underlying parent rock. The laterite for the stone circles would have been quarried locally and worked using iron tools. The stone circles are part of the Senogambian stone circle World Heritage Site and are the largest group o megalithic complexes recorded in any region of the world.

Flysch deposits, Basque Coast, Spain
Spain: We're heading to the Basque Coast UNESCO Global Geopark where a 5000m thick flysch deposit reveals a practically continuous record of 60 million years of Earth history. Within this sequence is evidence of the last of the five mass extinctions to have taken place over the course of the Earth’s history. This event (also known as the K/Pg extinction event), which was probably caused by a large asteroid striking the Earth some 65 million years ago in Chicxulub (Mexico), also led to the demise of the dinosaurs.

Sweden: Fossils of Orthoceras, an exitinct genus of nautiloid cephalopod are common in the many quarries on the Baltic island of Öland off the southern coast of Sweden. Quarries from Öland have supplied Europe with material for floors, stairs and gravestones for centuries as the hard limestone in which the fossils are found is very durable and the fossil inclusions make it even more desirable.

Switzerland: Switzerland is located right in the centre of the Alps, a mountain range that formed due to orogenic activity, and put very simply as a result of the collision of the African plate with the Eurasian plate. The Alps span France, Germany, Switzerland, Liechtenstein, Italy, Austria and Slovenia, but Switzerland is often described as being the most spectacular part!

Tunisia: We’ve chosen the Sidi Bouhlel Canyon, made famous in Star Wars . It was used during Episode IV and is where Luke Skywalker meets Obi-Wan Kenobi for the first time. The canyon is carved out of Middle Miocene sandstone and contains fossils of a number of vertebrates including crocodiles that provide vital evidence for changing palaeoclimate in the region.

Uruguay: The site we’ve chosen is the Grutas del Palacio or the Palace Caves. These unusual caves have been formed out of Late Cretaceous sandstone and get their name from the nearly 100 columns, each around 2m high that resemble those of a palace. The caves are part of the Grutas del Palacio UNESCO Global Geopark, located in the Flores Department near Trinidad in Uruguay.

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