1.
Elba
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Elba is a Mediterranean island in Tuscany, Italy,10 kilometres from the coastal town of Piombino, the largest island of the Tuscan Archipelago. Elba is also part of the Arcipelago Toscano National Park, and it is located in the Tyrrhenian Sea, about 50 kilometres east of the French island of Corsica. The island is part of the province of Livorno and is divided into eight municipalities, with a population of about 30,000 inhabitants. The municipalities are Portoferraio, which is also the principal town, along with Campo nellElba, Capoliveri, Marciana, Marciana Marina, Porto Azzurro, Rio Marina. Elba is the largest remaining stretch of land from the ancient tract that connected the Italian peninsula to Corsica. The island itself is made up of slices of rocks which formed part of the ancient Tethyan seafloor. These rocks have been through at least two orogenies, the Alpine orogeny and the Apennine orogeny, the second of these two events was associated with subduction of the Tethyan oceanic crust underneath Italy and the obduction of parts of the ancient seafloor onto the continents. Later extension within the inner part of the Apennine mountains caused adiabatic melting and the intrusion of the Mount Capanne. These igneous bodies brought with them skarn fluids which dissolved and replaced some of the carbonate units, one of the iron-rich minerals, ilvaite, was first identified on the island and takes its name from the Latin word for Elba. More recently, high-angle faults formed within the pile, allowing for the migration of iron-rich fluids through the crust. The deposits left behind by these formed the islands rich seams of iron ore. The terrain is varied, and is thus divided into several areas based on geomorphology. The mountainous and most recent part of the island can be found to the west, the mountain is home to many animal species including the mouflon and wild boar, two species that flourish despite the continuous influx of tourists. The central part of the island is a flat section with the width being reduced to just four kilometres. It is where the major centres can be found, Portoferraio, to the east is the oldest part of the island, formed over 3 million years ago. In the hilly area, dominated by Monte Calamita, are the deposits of iron that made Elba famous, rivers rarely exceed 3 kilometres in length, and it is common for the shorter ones to dry up during the summer. The climate of the island is predominantly Mediterranean, except for Mount Capanne, precipitation is concentrated in autumn and comprises a normal rainfall. The island lies in the shadow of the large and mountainous island of Corsica
2.
Pianosa
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The small island of Pianosa, about 10.25 km2 in area, has a coastal perimeter of 26 km and forms part of Italys Tuscan Archipelago in the Tyrrhenian Sea. In Roman times the island was named Planasia because of its flatness - its highest point stands at 29 m above sea level and it is a triangular-shaped land mass 14 km south west of Elba, and is a frazione of the municipality of Campo nellElba. The vegetation consists mainly of Mediterranean species as lentisco, fennel, juniperus, rosemary and pinus halepensis, the island is a stopping place for migrating birds in their seasonal passage from North to South. The sea around Pianosa is rich in fish because the coast was unapproachable for a long time, grouper, dory, dentex, moray, crawfish and many other species of fish inhabit the seas around the island. Fishing tools and ceramic of the Mesolithic were found as well as artefacts in quartz, the ancient Romans Planasia had buildings and was extensively cultivated. It became noted in history when the princeps Augustus banished his grandson, Postumus remained there until his murder by an assassin sent by Tiberius, around the death of Augustus in 14 AD. In the 4th century a small Christian community lived in Pianosa and these are on two levels and are the largest north of Rome,700 catacombs were discovered, indicating a fair number of residents. Pisa had the island in custody after the victory in a battle in those waters occurred in 874. In the Middle Ages the islands ownership was disputed by Pisa, in 1238 Genoa sent troops on the island supposing the inhabitants exercised the piracy, destroyed the village and the fortifications built by the Pisans and made prisoners the 150 inhabitants. Pianosa returned shortly after to Pisa, but Genoa had the supremacy of the Tyrrhenian Sea after the Battle of Meloria, the island returned to Pisan control under an agreement that required the Pisans leave it uncultivated and uninhabited, but the pact was not honoured. The Appiano family, who ruled Pisa, gave the island on rent to the family De Leis then to the Landi in 1344. The Holy Roman Emperor Charles V of Spain on August 15,1552 consigned to Cosimo I de Medici the Principality of Piombino in exchange of a loan of 200,000 scudi. On April 9,1809 the Archipelago returned to Tuscany, which was ruled by the French, on 10 May British marines and sailors from HMS Seahorse and HMS Halcyon landed on Pianosa, the landing parties destroyed the forts and captured about 100 prisoners during four hours of fighting. British losses were one killed and one wounded. The landing party also sent the farmers back to Elba and left the island a desert, napoleon went to Pianosa from Elba twice, rebuilt the tower, emplaced a garrison to defend the island, and built some houses to settle farmers. The Congress of Vienna assigned Elba and the Tuscan Archipelago to the Grand Duke of Tuscany. In 1864 a structure able to contain 350 prisoners was built, the captives cultivated cereals, produced oil and wine as Sangiovese and Procanico, there were poultry, pigs, and cattle farms. From 1884 until 1965 Pianosa, because of its dry climate, hosted convicts, coming from all over Italy, at the beginning of the 1900s, the population on the island was 21 civilians,80 prison guards,40 soldiers, and 800 prisoners
3.
Montecristo
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Montecristo, formerly Oglasa, is an island in the Tyrrhenian Sea and part of the Tuscan Archipelago. Administratively it belongs to the municipality of Portoferraio in the province of Livorno, Italy. The island has an area of 10.39 km2, it is approximately 4.1 km wide at its widest point and is 3.4 km long, the coasts are steep, and extend for 16 km. The island is a nature reserve and forms part of the Tuscan Archipelago National Park. Much of the fame is derived from the fact that it provides the setting for part of the novel The Count of Monte Cristo. The history of the island begins with the Iron Age, the Etruscans exploited the forests of oak needed to fuel the bloomeries of the mainland where the iron ore of Elbas mines was melted. The Greeks gave Montecristo its oldest known name, Oglasa or Ocrasia, the Romans, however, knew it under the name Mons Jovis, and erected an altar to Iuppiter Optimus Maximus on the highest mountain, of which some traces remain. During the imperial age, the Romans opened some quarries to extract granite, perhaps used in the construction of villas on the islands of Giglio, Elba, and Giannutri. Around the middle of the fifth century AD, the caves of the island home to several hermits escaping from the Vandals of Genseric. They christened the island Mons Christi, from which the name is derived. At the beginning of the century, Pope Gregory the Great submitted them to the monastic rule of the Benedictines. In 1216, the joined the order of the Camaldolese. Thanks to the donations of several families, the monastery became powerful and rich. The island was once a possession of Pisa, but was acquired by the Principality of Piombino. In 1553, Ottoman pirate Dragut, heading for Elba, stormed the monastery, enslaved the monks, after that, the island was uninhabited. In the second half of the century, together with most of the Tuscan Archipelago, it became part of the Stato dei Presidi. The island was annexed to the French Empire under Napoleon, after his fall, the first attempts to colonise Monte Cristo, at the time owned by Charles Cambiagi, were made in 1840 by two German hermits, Augustin Eulhardt and Joseph Keim, who eventually abandoned the attempt. In 1843, other people arrived with the intention of cultivating the island, young Tyrolean Adolph Franz Obermüller, also during 1843, there were other attempts of colonisation by French agriculturalist George Guiboud, which ended with yet another failure
4.
Isola del Giglio
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Isola del Giglio is an Italian island and comune situated in the Tyrrhenian Sea, off the coast of Tuscany, and is part of the Province of Grosseto. The island is one of seven that form the Tuscan Archipelago, the island is separated by a 16-kilometre stretch of sea from the nearest point of the mainland, the promontory of Monte Argentario. Mainly mountainous, it consists almost entirely of granite, culminating in the Poggio della Pagana, ninety percent of its surface is covered by Mediterranean vegetation, alternating with large pine forests and numerous vineyards which allow the production of the local Ansonaco wine. The coast is 27 kilometres long, made up of rocks, smooth cliffs and several bays, Arenella, Cannelle, Caldane and Campese, the municipality is composed of the islands of Giglio and Giannutri. Three principal settlements are located on the island, Giglio Porto, located on the eastern coastal side. It is divided into the quarters of Chiesa, Moletto and Saraceno, Giglio Castello, located upon a hill between the two other localities and characterized by the majestic walls of a fortress. It is divided into the quarters of Casamatta, Centro, Cisterna, Giglio Campese, it is located on the north-western coastal side and is a modern sea resort. The modern island was formed probably 4.5 to 5 million years ago, later, it was probably an Etruscan military stronghold. Wondering, Igiliums wooded heights I view Afar, and must not cheat them of the praise Due to their fame. In 1241, the Sicilian and Pisan fleet of Emperor Frederick II destroyed a Genoese fleet in the Battle of Giglio, from 1264, Isola del Giglio was a Pisan dominion, from which it passed to the Medici family. It suffered several Saracen attacks, which ended only in 1799, on 14 June 1646, Grand Admiral Jean Armand de Maillé-Brézé was killed at the Battle of Orbetello, at sunset on his flagship the Grand Saint Louis. Alongside its history, the island was always renowned for its ore, many columns. The island houses the remains of a Roman villa of Domitius Ahenobarbus, no traces of the once existing Temple of Diana can be seen now. The church of San Pietro Apostolo in Giglio Castello has a crucifix attributed to the sculptor Giambologna. The island is also the site of an Etruscan shipwreck dating back to the early Iron age, the cargo of the ship included copper and lead ingots, iron spits, amphorae and a Corinthian helmet. Even a wooden writing tablet with stylus was preserved, the finds are almost completely lost now. Isola del Giglio is connected to Tuscany by ferries Toremar and Maregiglio, in 2012, the island received prolonged international media attention, following the 13 January 2012 running aground of the cruise liner Costa Concordia, just off the islands shore. Most of the more than 4,200 passengers and crew were rescued and taken to the island, at least 30 people died and 64 were injured, with 2 missing. The people of the rushed to help, providing hot drinks and blankets
5.
Giannutri
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The island has a coastal perimeter of 11 km, is stretched approximately 2.8 km from Punta del Capo Rosso to Punta Secca and 2 km from Punta San Francesco to Punta della Salvezza. The island landscape has three hills, Poggio del Cannone and Monte Mario in the part and Poggio Capel Rosso. The island’s flora is prevalently a high macchia mediterranea in the part which become garrigue in the southern. The mild climate has favoured the growth of such as euphorbia, palm trees. The marine flora is abundant in sponges, madreporaria, black coral, the island, as all that of the Tuscan Archipelago, is a place where the bird migration take a stop along their seasonal movement from North to South. The Audouins gull, Puffinus yelkouan, Black-eared wheatear, Marmoras warbler, Giannutri was mentioned by Pliny the Elder in his Naturalis Historiae and by the Latin geographer Pomporio Mela in his Dechorographia. The island was inhabited by Romans of which are the vestiges of a magnificent Roman villa, remained locked for almost 15 years, in 1806 a small military garrison was sent on the island. On 10 May 1809, a party from HMS Seahorse and HMS Halcyon landed on the Pianosa. The landing party destroyed the forts and captured about 100 prisoners during four hours of fighting. British losses were one killed and one wounded. The Minister of Finances Quintino Sella, with a Royal decree, in 1908 the Comune sold the island to the family Ruffo della Scaletta which remained the owner until the death of the Prince Rufo. In the 1960s and 1970s the real estate investing transformed radically the island, in a few years an holiday resort at Cala Spalmatoio and many houses scattered through the island were built. The Società Porto Romano declared bankruptcy and the owners of the houses were obliged to form a society, called Libero Consorzio Giannutri. Villa Domizia, also known as Villa Domitia was built probably in the 1st or 2nd century by the Gnaeus Domitius Ahenobarbus who was the owner of the island. The Villa is placed in the part of the island on an height, close to Punta Scaletta and Cala Maestra. The rooms employed as residence and the others were disposed on the highest level accessible by stairs, in the back of the residential quarter are the remains of a long building, with 8 rooms aligned, likely used by the monks as convent and since then called Conventaccio. The Villa is connected to Cala Maestra through a set of stairs, the Calidarium, formed by a rectangular room from whose walls passed the warm air, was placed halfway between the Villa and Cala Maestra and was richly adorned with marbles and mosaic floor. The Romans built a harbour and a wharf at Cala Maestra cutting the rock in order to have more space
6.
Italy
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Italy, officially the Italian Republic, is a unitary parliamentary republic in Europe. Located in the heart of the Mediterranean Sea, Italy shares open land borders with France, Switzerland, Austria, Slovenia, San Marino, Italy covers an area of 301,338 km2 and has a largely temperate seasonal climate and Mediterranean climate. Due to its shape, it is referred to in Italy as lo Stivale. With 61 million inhabitants, it is the fourth most populous EU member state, the Italic tribe known as the Latins formed the Roman Kingdom, which eventually became a republic that conquered and assimilated other nearby civilisations. The legacy of the Roman Empire is widespread and can be observed in the distribution of civilian law, republican governments, Christianity. The Renaissance began in Italy and spread to the rest of Europe, bringing a renewed interest in humanism, science, exploration, Italian culture flourished at this time, producing famous scholars, artists and polymaths such as Leonardo da Vinci, Galileo, Michelangelo and Machiavelli. The weakened sovereigns soon fell victim to conquest by European powers such as France, Spain and Austria. Despite being one of the victors in World War I, Italy entered a period of economic crisis and social turmoil. The subsequent participation in World War II on the Axis side ended in defeat, economic destruction. Today, Italy has the third largest economy in the Eurozone and it has a very high level of human development and is ranked sixth in the world for life expectancy. The country plays a prominent role in regional and global economic, military, cultural and diplomatic affairs, as a reflection of its cultural wealth, Italy is home to 51 World Heritage Sites, the most in the world, and is the fifth most visited country. The assumptions on the etymology of the name Italia are very numerous, according to one of the more common explanations, the term Italia, from Latin, Italia, was borrowed through Greek from the Oscan Víteliú, meaning land of young cattle. The bull was a symbol of the southern Italic tribes and was often depicted goring the Roman wolf as a defiant symbol of free Italy during the Social War. Greek historian Dionysius of Halicarnassus states this account together with the legend that Italy was named after Italus, mentioned also by Aristotle and Thucydides. The name Italia originally applied only to a part of what is now Southern Italy – according to Antiochus of Syracuse, but by his time Oenotria and Italy had become synonymous, and the name also applied to most of Lucania as well. The Greeks gradually came to apply the name Italia to a larger region, excavations throughout Italy revealed a Neanderthal presence dating back to the Palaeolithic period, some 200,000 years ago, modern Humans arrived about 40,000 years ago. Other ancient Italian peoples of undetermined language families but of possible origins include the Rhaetian people and Cammuni. Also the Phoenicians established colonies on the coasts of Sardinia and Sicily, the Roman legacy has deeply influenced the Western civilisation, shaping most of the modern world
7.
Tuscany
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Tuscany is a region in central Italy with an area of about 23,000 square kilometres and a population of about 3.8 million inhabitants. Tuscany is known for its landscapes, traditions, history, artistic legacy, Tuscany produces wines, including Chianti, Vino Nobile di Montepulciano, Morellino di Scansano and Brunello di Montalcino. Having a strong linguistic and cultural identity, it is considered a nation within a nation. Tuscany is traditionally a popular destination in Italy, and the main tourist destinations by number of tourist arrivals are Florence, Pisa, Montecatini Terme, Castiglione della Pescaia and Grosseto. The village of Castiglione della Pescaia is also the most visited destination in the region. Additionally, Siena, Lucca, the Chianti region, Versilia and Val dOrcia are also internationally renowned, Tuscany has over 120 protected nature reserves, making Tuscany and its capital Florence popular tourist destinations that attract millions of tourists every year. In 2012, the city of Florence was the worlds 89th most visited city, roughly triangular in shape, Tuscany borders the regions of Liguria to the northwest, Emilia-Romagna to the north and east, Umbria to the east and Lazio to the southeast. The comune of Badia Tedalda, in the Tuscan Province of Arezzo, has an exclave named Ca Raffaello within Emilia-Romagna, Tuscany has a western coastline on the Tyrrhenian Sea, containing the Tuscan Archipelago, of which the largest island is Elba. Tuscany has an area of approximately 22,993 square kilometres, surrounded and crossed by major mountain chains, and with few plains, the region has a relief that is dominated by hilly country used for agriculture. Hills make up nearly two-thirds of the total area, covering 15,292 square kilometres, and mountains. Plains occupy 8. 4% of the total area—1,930 square kilometres —mostly around the valley of the River Arno, many of Tuscanys largest cities lie on the banks of the Arno, including the capital Florence, Empoli and Pisa. The pre-Etruscan history of the area in the late Bronze and Iron Ages parallels that of the early Greeks, following this, the Villanovan culture saw Tuscany, and the rest of Etruria, taken over by chiefdoms. City-states developed in the late Villanovan before Orientalization occurred and the Etruscan civilization rose, the Etruscans created the first major civilization in this region, large enough to establish a transport infrastructure, to implement agriculture and mining and to produce vibrant art. The Etruscans lived in Etruria well into prehistory, throughout their existence, they lost territory to Magna Graecia, Carthage and Celts. Despite being seen as distinct in its manners and customs by contemporary Greeks, the cultures of Greece, one reason for its eventual demise was this increasing absorption by surrounding cultures, including the adoption of the Etruscan upper class by the Romans. Soon after absorbing Etruria, Rome established the cities of Lucca, Pisa, Siena, and Florence, endowed the area with new technologies and development, and ensured peace. These developments included extensions of existing roads, introduction of aqueducts and sewers, however, many of these structures have been destroyed by erosion due to weather. The Roman civilization in the West collapsed in the 5th century AD, in the years following 572, the Longobards arrived and designated Lucca the capital of their Duchy of Tuscia
8.
Portoferraio
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Portoferraio is a town and comune in the province of Livorno, on the edge of the eponymous harbour of the island of Elba. It is the islands largest city, because of its terrain, many of its buildings are situated on the slopes of a tiny hill surrounded on three sides by the sea. It was founded by Cosimo I de Medici, Grand Duke of Tuscany, in 1548, with the name of Cosmopoli and it had three forts and a massive line of walls, all still visible today. The city remained to the Grand Duchy of Tuscany until the 18th century, a British garrison withstood the Siege of Porto Ferrajo in 1801, but the 1802 Treaty of Amiens transferred the town to France. In 1814 it was handed over to Napoleon Bonaparte, as the seat of his first exile, in the 19th century, the city grew quickly, due to the construction of infrastructures and the exploitation of new iron mills in Rio Marina. Portoferraio then became the shipping port of the ore towards the mainland, whence the current name. After the end of the Napoleonic Era, Portoferraio returned to Tuscany, here brigand Carmine Crocco was imprisoned until his death for his revolution against the reign of Victor Emmanuel II and the anarchist Giovanni Passannante who attempted to kill king Umberto I. During World War II, Portoferraio became the scene of battle when Elba was occupied by German forces, in late June 1944, an Allied force composed mainly of Free French troops liberated the island in a fight which lasted two days. Portoferraio was taken by French troops on 18 June, but was damaged by the fighting, portoferraios economy suffered from the end of mining activities starting from the 1970s, but in the following decades it gained a status as an internationally renowned tourist resort. The town center is crowded around the small marina drawn in a natural cove and it was built by Leopod II Grand Duke of Tuscany in 1788, the stone tower is 25 metres high and has a double balcony and lantern. On the same tower is an additional light identified by the number 2072.2. E. F. that emits a red fixed light at 60 metres above sea level
9.
Corsica
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Corsica is an island in the Mediterranean Sea and one of the 13 regions of France. It is located west of the Italian Peninsula, southeast of the French mainland, a single chain of mountains make up two-thirds of the island. While being part of France, Corsica is also designated as a territorial collectivity by law, as a territorial collectivity, Corsica enjoys a greater degree of autonomy than other French regions, for example, the Corsican Assembly is able to exercise limited executive powers. The island formed a single department until it was split in 1975 into two departments, Haute-Corse and Corse-du-Sud, with its capital in Ajaccio, the prefecture city of Corse-du-Sud. Bastia, the city of Haute-Corse, is the second-largest settlement in Corsica. After being ruled by the Republic of Genoa since 1284, Corsica was briefly an independent Corsican Republic from 1755 until it was conquered by France in 1769. Due to Corsicas historical ties with the Italian peninsula, the island retains to this day many elements of the culture of Italy, the native Corsican language, whose northern variant is closely related to the Italian language, is recognised as a regional language by the French government. This Mediterranean island was ruled by various nations over the course of history but had several periods of independence. Napoleon was born in 1769 in the Corsican capital of Ajaccio and his ancestral home, Maison Bonaparte, is today used as a museum. The origin of the name Corsica is subject to much debate, to the Ancient Greeks it was known as Kalliste, Corsis, Cyrnos, Cernealis, or Cirné. Of these Cyrnos, Cernealis, or Cirné derive from a corruption of the most ancient Greek name of the island, Σειρηνούσσαι, the claim that latter Greek names are based on the Phoenician word for peninsula are highly unlikely. Corsica has been occupied continuously since the Mesolithic era and it acquired an indigenous population that was influential in the Mediterranean during its long prehistory. The Romans, who built a colony in Aléria, considered Corsica as one of the most backward regions of the Roman world, the island produced sheep, honey, resin and wax, and exported many slaves, not well considered because of their fierce and rebellious character. Moreover, it was known for its wines, exported to Rome. Administratively, the island was divided in pagi, which in the Middle Ages became the pievi, Corsica was integrated by Emperor Diocletian in Roman Italy. In the 5th century, the half of the Roman Empire collapsed, and the island was invaded by the Vandals. Briefly recovered by the Byzantines, it became part of the Kingdom of the Lombards—this made it a dependency of the March of Tuscany. Pepin the Short, king of the Franks and Charlemagnes father, expelled the Lombards, in the first quarter of the 11th century, Pisa and Genoa together freed the island from the threat of Arab invasion
10.
Sardinia
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Sardinia is the second largest island in the Mediterranean Sea and an autonomous region of Italy. It is located in the Western Mediterranean, just south of the French island of Corsica, the regions official name is Regione Autonoma della Sardegna / Regione Autònoma de Sardigna, and its capital and largest city is Cagliari. It is divided into four provinces and a metropolitan city and its indigenous language and the other minority languages spoken by the Sardinians enjoy equal dignity with Italian under regional law. The name Sardinia is from the pre-Roman noun *srd-, later romanised as sardus and it makes its first appearance on the Nora Stone, where the word Šrdn testifies to the names existence when the Phoenician merchants first arrived. According to Timaeus, one of Platos dialogues, Sardinia and its people as well might have named after Sardò. There has also been speculation that identifies the ancient Nuragic Sards with the Sherden, in Classical antiquity, Sardinia was called Ichnusa, Σανδάλιον Sandal, Sardinia and Sardó. Sardinia is the second-largest island in the Mediterranean Sea, with an area of 24,100 square kilometres and it is situated between 38°51 and 41°18 latitude north and 8°8 and 9°50 east longitude. To the west of Sardinia is the Sea of Sardinia, a unit of the Mediterranean Sea, to Sardinias east is the Tyrrhenian Sea, the nearest land masses are the island of Corsica, the Italian Peninsula, Sicily, Tunisia, the Balearic Islands, and Provence. The Tyrrhenian Sea portion of the Mediterranean Sea is directly to the east of Sardinia between the Sardinian east coast and the west coast of the Italian mainland peninsula, the Strait of Bonifacio is directly north of Sardinia and separates Sardinia from the French island of Corsica. The island has an ancient geoformation and, unlike Sicily and mainland Italy, is not earthquake-prone and its rocks date in fact from the Palaeozoic Era. Due to long erosion processes, the highlands, formed of granite, schist, trachyte, basalt, sandstone and dolomite limestone. The highest peak is Punta La Marmora, part of the Gennargentu Ranges in the centre of the island. The islands ranges and plateaux are separated by wide valleys and flatlands. Sardinia has few rivers, the largest being the Tirso,151 km long, which flows into the Sea of Sardinia, the Coghinas. There are 54 artificial lakes and dams that supply water and electricity, the main ones are Lake Omodeo and Lake Coghinas. The only natural lake is Lago di Baratz. A number of large, shallow, salt-water lagoons and pools are located along the 1,850 km of the coastline, the climate of the island is variable from area to area, due to several factors including the extension in latitude and the elevation. During the year there is a concentration of rainfall in the winter and autumn, some heavy showers in the spring
11.
Igneous rock
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Igneous rock, or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or lava, the magma can be derived from partial melts of existing rocks in either a planets mantle or crust. Typically, the melting is caused by one or more of three processes, an increase in temperature, a decrease in pressure, or a change in composition, solidification into rock occurs either below the surface as intrusive rocks or on the surface as extrusive rocks. Igneous rock may form with crystallization to form granular, crystalline rocks, Igneous and metamorphic rocks make up 90–95% of the top 16 km of the Earths crust by volume. Igneous rocks form about 15% of the Earths current land surface, most of the Earths oceanic crust is made of igneous rock. In terms of modes of occurrence, igneous rocks can be either intrusive or extrusive, the mineral grains in such rocks can generally be identified with the naked eye. Intrusive rocks can also be classified according to the shape and size of the intrusive body, typical intrusive formations are batholiths, stocks, laccoliths, sills and dikes. When the magma solidifies within the earths crust, it cools slowly forming coarse textured rocks, such as granite, gabbro, the central cores of major mountain ranges consist of intrusive igneous rocks, usually granite. When exposed by erosion, these cores may occupy huge areas of the Earths surface, intrusive igneous rocks that form at depth within the crust are termed plutonic rocks and are usually coarse-grained. Intrusive igneous rocks that form near the surface are termed subvolcanic or hypabyssal rocks, hypabyssal rocks are less common than plutonic or volcanic rocks and often form dikes, sills, laccoliths, lopoliths, or phacoliths. Extrusive igneous rocks, also known as rocks, are formed at the crusts surface as a result of the partial melting of rocks within the mantle. Extrusive igneous rocks cool and solidify quicker than intrusive igneous rocks and they are formed by the cooling of molten magma on the earths surface. The magma, which is brought to the surface through fissures or volcanic eruptions, hence such rocks are smooth, crystalline and fine-grained. Basalt is an extrusive igneous rock and forms lava flows, lava sheets. Some kinds of basalt solidify to form long polygonal columns, the Giants Causeway in Antrim, Northern Ireland is an example. The molten rock, with or without suspended crystals and gas bubbles, is called magma and it rises because it is less dense than the rock from which it was created. When magma reaches the surface from beneath water or air, it is called lava, eruptions of volcanoes into air are termed subaerial, whereas those occurring underneath the ocean are termed submarine. Black smokers and mid-ocean ridge basalt are examples of volcanic activity
12.
Sedimentary rock
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Sedimentary rocks are types of rock that are formed by the deposition and subsequent cementation of that material at the Earths surface and within bodies of water. Sedimentation is the name for processes that cause mineral and/or organic particles to settle in place. The particles that form a rock by accumulating are called sediment. Sedimentation may also occur as minerals precipitate from solution or shells of aquatic creatures settle out of suspension. The sedimentary rock cover of the continents of the Earths crust is extensive, sedimentary rocks are only a thin veneer over a crust consisting mainly of igneous and metamorphic rocks. Sedimentary rocks are deposited in layers as strata, forming a structure called bedding, sedimentary rocks are also important sources of natural resources like coal, fossil fuels, drinking water or ores. The study of the sequence of rock strata is the main source for an understanding of the Earths history, including palaeogeography, paleoclimatology. The scientific discipline that studies the properties and origin of rocks is called sedimentology. Sedimentology is part of both geology and physical geography and overlaps partly with other disciplines in the Earth sciences, such as pedology, geomorphology, geochemistry, sedimentary rocks have also been found on Mars. Clastic sedimentary rocks are composed of rock fragments that were cemented by silicate minerals. Clastic rocks are composed largely of quartz, feldspar, rock fragments, clay minerals, and mica, any type of mineral may be present, clastic sedimentary rocks, are subdivided according to the dominant particle size. Most geologists use the Udden-Wentworth grain size scale and divide unconsolidated sediment into three fractions, gravel, sand, and mud and this tripartite subdivision is mirrored by the broad categories of rudites, arenites, and lutites, respectively, in older literature. The subdivision of these three categories is based on differences in clast shape, conglomerates and breccias), composition. Conglomerates are dominantly composed of rounded gravel, while breccias are composed of dominantly angular gravel, composition of framework grains The relative abundance of sand-sized framework grains determines the first word in a sandstone name. Naming depends on the dominance of the three most abundant components quartz, feldspar, or the lithic fragments that originated from other rocks, all other minerals are considered accessories and not used in the naming of the rock, regardless of abundance. Clean sandstones with open space are called arenites. Muddy sandstones with abundant muddy matrix are called wackes, six sandstone names are possible using the descriptors for grain composition and the amount of matrix. Mudrocks are sedimentary rocks composed of at least 50% silt- and clay-sized particles and these relatively fine-grained particles are commonly transported by turbulent flow in water or air, and deposited as the flow calms and the particles settle out of suspension
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