The Jurassic is a geologic period and system that spans 56.3 million years from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period 145 Mya. The Jurassic constitutes the middle period of the Mesozoic Era, known as the Age of Reptiles, the start of the period is marked by the major Triassic–Jurassic extinction event. The Jurassic is named after the Jura Mountains within the European Alps, by the beginning of the Jurassic, the supercontinent Pangaea had begun rifting into two landmasses, Laurasia to the north and Gondwana to the south. This created more coastlines and shifted the continental climate from dry to humid, on land, the fauna transitioned from the Triassic fauna, dominated by both dinosauromorph and crocodylomorph archosaurs, to one dominated by dinosaurs alone. The first birds appeared during the Jurassic, having evolved from a branch of theropod dinosaurs, other major events include the appearance of the earliest lizards, and the evolution of therian mammals, including primitive placentals.
Crocodilians made the transition from a terrestrial to a mode of life. The oceans were inhabited by marine reptiles such as ichthyosaurs and plesiosaurs, the chronostratigraphic term Jurassic is directly linked to the Jura Mountains. The name Jura is derived from the Celtic root jor, which was Latinised into juria, the Jurassic period is divided into the Early Jurassic and Late Jurassic epochs. The Jurassic System, in stratigraphy, is divided into the Lower Jurassic, the separation of the term Jurassic into three sections goes back to Leopold von Buch. The Jurassic North Atlantic Ocean was relatively narrow, while the South Atlantic did not open until the following Cretaceous period, the Tethys Sea closed, and the Neotethys basin appeared. Climates were warm, with no evidence of glaciation, as in the Triassic, there was apparently no land over either pole, and no extensive ice caps existed. In contrast, the North American Jurassic record is the poorest of the Mesozoic, the Jurassic was a time of calcite sea geochemistry in which low-magnesium calcite was the primary inorganic marine precipitate of calcium carbonate.
Carbonate hardgrounds were thus very common, along with calcitic ooids, calcitic cements, the first of several massive batholiths were emplaced in the northern American cordillera beginning in the mid-Jurassic, marking the Nevadan orogeny. Important Jurassic exposures are found in Russia, South America, Australasia. As the Jurassic proceeded and more groups of dinosaurs like sauropods and ornithopods proliferated in Africa. Middle Jurassic strata are well represented nor well studied in Africa. Late Jurassic strata are poorly represented apart from the spectacular Tendaguru fauna in Tanzania, the Late Jurassic life of Tendaguru is very similar to that found in western North Americas Morrison Formation. During the Jurassic period, the primary living in the sea were fish
The Molasse basin is a foreland basin north of the Alps which formed during the Oligocene and Miocene epochs. The basin formed as a result of the flexure of the European plate under the weight of the wedge of the Alps that was forming to the south. In geology, the molasse basin is sometimes used in a general sense for a synorogenic foreland basin of the type north of the Alps. The Molasse basin stretches over a length of 1000 kilometers along the axis of the Alps, in France, Germany. The western end is at Lake Geneva, where the outcrop is just 20 km wide. Further to the northeast the basin becomes wider and it forms the subsurface of the Swiss Mittelland and reaches its largest width in the Bavarian foreland of the Alps. From Amstetten to Sankt Pölten the basin forms a narrow band, after that it widens again to the east. North of the Danube River it connects with the Vienna basin, the region where the molasse crops out is divided into two. The Subalpine Molasse zone along the Alps and the Foreland Molasse zone further into the foreland, in the Foreland Molasse zone the molasse sediments are relatively undisturbed, in the Subalpine Molasse zone the beds are often tilted and thrust over each other.
Before the development of the Molasse basin, in the Mesozoic era, the weight of the orogenic wedge made the European plate bend downward, resulting in the formation of a deep marine foredeep. In the Eocene epoch the basin became deeper until it formed a small oceanic trench north of the developing orogen, due to the huge amounts of sediments that were eroded from the forming mountain chain the basin was filled up and got shallower. During the Oligocene and Miocene epochs, undeep marine to continental molasse was deposited in the basin, around 10 to 5 million years ago, tectonic uplift had raised the basin to such a height that netto sedimentation stopped. From the south, the deposits were overthrust about 10 kilometers by the Helvetic nappes. The Jura mountains, a fold and thrust belt along the present Swiss-French border, in some places in the Jura mountains, molasse deposits were folded together with older Mesozoic limestones. Deformation instead localized further north, thus forming the relatively flat Swiss Mittelland between the Alps and the Jura Mountains, the Swiss part of the Molasse basin is now located in between the Alps and the Jura mountains, as a large piggy-back basin.
In the Eastern Alps an external mountain range such as the Jura Mountains never developed, the total thickness of molasse deposits in the basin can be up to 6 kilometers. Lithostratigraphically, this molasse is treated as a group that is divided into four formations and this division is made on whether the sedimentary facies is continental or marine. The lowermost formation is the Lower Marine Molasse and its age is Rupelian and it consists of shallow marine sand and marl
The Cretaceous is a geologic period and system that spans 79 million years from the end of the Jurassic Period 145 million years ago to the beginning of the Paleogene Period 66 Mya. It is the last period of the Mesozoic Era, the Cretaceous Period is usually abbreviated K, for its German translation Kreide. The Cretaceous was a period with a warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now-extinct marine reptiles and rudists, during this time, new groups of mammals and birds, as well as flowering plants, appeared. The Cretaceous ended with a mass extinction, the Cretaceous–Paleogene extinction event, in which many groups, including non-avian dinosaurs, pterosaurs. The end of the Cretaceous is defined by the abrupt Cretaceous–Paleogene boundary, the name Cretaceous was derived from Latin creta, meaning chalk. The Cretaceous is divided into Early and Late Cretaceous epochs, or Lower and Upper Cretaceous series, in older literature the Cretaceous is sometimes divided into three series, Neocomian and Senonian.
A subdivision in eleven stages, all originating from European stratigraphy, is now used worldwide, in many parts of the world, alternative local subdivisions are still in use. As with other geologic periods, the rock beds of the Cretaceous are well identified. No great extinction or burst of diversity separates the Cretaceous from the Jurassic and this layer has been dated at 66.043 Ma. A140 Ma age for the Jurassic-Cretaceous boundary instead of the usually accepted 145 Ma was proposed in 2014 based on a study of Vaca Muerta Formation in Neuquén Basin. Víctor Ramos, one of the authors of the study proposing the 140 Ma boundary age sees the study as a first step toward formally changing the age in the International Union of Geological Sciences, due to the high sea level there was extensive space for such sedimentation. Because of the young age and great thickness of the system. Chalk is a type characteristic for the Cretaceous. It consists of coccoliths, microscopically small calcite skeletons of coccolithophores, the group is found in England, northern France, the low countries, northern Germany, Denmark and in the subsurface of the southern part of the North Sea.
Chalk is not easily consolidated and the Chalk Group still consists of sediments in many places. The group has other limestones and arenites, among the fossils it contains are sea urchins, belemnites and sea reptiles such as Mosasaurus. In southern Europe, the Cretaceous is usually a marine system consisting of competent limestone beds or incompetent marls
Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, yet the non-oceanic borders of Europe—a concept dating back to classical antiquity—are arbitrary. Europe covers about 10,180,000 square kilometres, or 2% of the Earths surface, Europe is divided into about fifty sovereign states of which the Russian Federation is the largest and most populous, spanning 39% of the continent and comprising 15% of its population. Europe had a population of about 740 million as of 2015. Further from the sea, seasonal differences are more noticeable than close to the coast, Europe, in particular ancient Greece, was the birthplace of Western civilization. The fall of the Western Roman Empire, during the period, marked the end of ancient history. Renaissance humanism, exploration and science led to the modern era, from the Age of Discovery onwards, Europe played a predominant role in global affairs. Between the 16th and 20th centuries, European powers controlled at times the Americas, most of Africa, Oceania.
The Industrial Revolution, which began in Great Britain at the end of the 18th century, gave rise to economic and social change in Western Europe. During the Cold War, Europe was divided along the Iron Curtain between NATO in the west and the Warsaw Pact in the east, until the revolutions of 1989 and fall of the Berlin Wall. In 1955, the Council of Europe was formed following a speech by Sir Winston Churchill and it includes all states except for Belarus and Vatican City. Further European integration by some states led to the formation of the European Union, the EU originated in Western Europe but has been expanding eastward since the fall of the Soviet Union in 1991. The European Anthem is Ode to Joy and states celebrate peace, in classical Greek mythology, Europa is the name of either a Phoenician princess or of a queen of Crete. The name contains the elements εὐρύς, broad and ὤψ eye, broad has been an epithet of Earth herself in the reconstructed Proto-Indo-European religion and the poetry devoted to it.
For the second part the divine attributes of grey-eyed Athena or ox-eyed Hera. The same naming motive according to cartographic convention appears in Greek Ανατολή, Martin Litchfield West stated that phonologically, the match between Europas name and any form of the Semitic word is very poor. Next to these there is a Proto-Indo-European root *h1regʷos, meaning darkness. Most major world languages use words derived from Eurṓpē or Europa to refer to the continent, in some Turkic languages the originally Persian name Frangistan is used casually in referring to much of Europe, besides official names such as Avrupa or Evropa
In paleogeography, Gondwanaland, is the name given to an ancient supercontinent. It is believed to have sutured about 600 to 530 million years ago, Gondwana formed prior to Pangaea, and became part of it. Around 335 to 250 million years ago Gondwana and Laurasia joined together to form the supercontinent Pangaea, Gondwana separated from Laurasia in the breakup of Pangaea, drifting farther south after the split. Gondwana itself also broke apart, the continent of Gondwana was named by Austrian scientist Eduard Suess, after the Gondwana region of central northern India which is derived from Sanskrit for forest of the Gonds. The name had previously used in a geological context, first by H. B. From which the Gondwana sedimentary sequences are described, for example, the plant family Proteaceae, known only from southern South America, South Africa and New Zealand, is considered to have a Gondwanan distribution. This pattern is considered to indicate an archaic, or relict. The assembly of Gondwana was a protracted process, several orogenies led to its final amalgamation 550 to 500 million years ago at the end of the Ediacaran, and into the Cambrian.
These include the Brasiliano Orogeny, the East African Orogeny, the Malagasy Orogeny, the final stages of Gondwanan assembly overlapped with the opening of the Iapetus Ocean between Laurentia and western Gondwana. During this interval, the Cambrian explosion occurred and this is the Famatinian block and it formerly continued the line of the Appalachians southwards. One of the sites of Gondwanan amalgamation was the East African Orogeny. The East African Orogeny at about 650–630 Mya affected a part of Arabia, north-eastern Africa, East Africa. Collins and Windley propose that in this orogeny, Azania collided with the Congo–Tanzania–Bangweulu Block, the Malagasy orogeny at about 550–515 Mya affected Madagascar, eastern East Africa and southern India. In it, Neoproterozoic India collided with the already combined Azania and Congo–Tanzania–Bangweulu Block, at the same time, in the Kunga Orogeny Neoproterozoic India collided with the Australia/Mawson continent. Other large continental masses, including the core cratons of North America, when Pangaea broke up, two large masses and Laurasia, were formed.
During the late Paleozoic, Gondwana extended from a point at or near the South Pole to near the Equator, across much of Gondwana, the climate was mild. During the Mesozoic, the world was on average warmer than it is today. Gondwana was host to a variety of flora and fauna for many millions of years
Geology of Europe
The geology of Europe is varied and complex, and gives rise to the wide variety of landscapes found across the continent, from the Scottish Highlands to the rolling plains of Hungary. These two halves are separated by the Pyrenees and the Alps-Carpathians mountain chain, the northern plains are delimited in the west by the Scandinavian Mountains and the mountainous parts of the British Isles. The southern mountainous region is bounded by the Mediterranean Sea, major shallow water bodies submerging parts of the northern plains are the Celtic Sea the North Sea, the Baltic Sea complex and Barents Sea. From the standpoint of plate tectonics, the ongoing northward drive of the African plate into the Eurasian plate in the Mediterranean basin is the most prominent aspect of the European scene today. The pressure exerted by the African plate is the cause of the rise of the Pyrenees, the Alps. Limestones and other sediments, the ancient floor of the Tethys Sea, are pushed high, a submarine back-arc basin develops south of Italy, which is one of several Mediterranean mini-continental fragments caught between the two plates.
This buckling of the Earths crust forces up Italys mountains and stimulates active faults, another separate terrain unit, has been rotated and emplaced against the rest of Europe by the plate collision. Moving north from the Alps and other ranges, tectonic activity largely fades away in the stable Baltic craton, laurentian fragments - Western Norway and Scotland, Gondwana Fragments - Spain, Italy. Malta, possibly belonging to the Cimmerian Arc, Neo-Tethys Ocean floor - the Pyrenees/Alps/Apennine/Balkan Alps/Carpathian complex, geography of Europe European Cenozoic Rift System Geology of Europe OneGeology-Europe Maps showing the tectonic development of Europe
Southern Alps (Europe)
The Southern Alps are a geological subdivision of Alps that are found south of the Periadriatic Seam, a major geological faultzone across the Alps. The southern Alps contain almost the same area as the Southern Limestone Alps, the rocks of the southern Alps gradually go over in the Dinarides or Dinaric Alps to the south-east. In the south-west they disappear below recent sediments of the Po basin that are lying discordant on top of them, the Southern Alps are composed of material from the Adriatic or Apulian tectonic plate, the area is a part of this plate. These are mainly Mesozoic sedimentary rocks, most of them limestones, in contradiction to the Central Eastern Alps north of the Periadriatic Seam, the geology of the Southern Alps is not characterized by nappes. Neither are high grade metamorphic rocks common in the region, the Southern Alps are tectonically characterized by large scale thrusting and folding to the south, the dominant vergence in the region is southward. As is the case in the foreland of the Pyrenees.
To the west, south of the Valle dAosta, the Southern Alps form a huge monocline, geology of the Alps Part 1, General remarks, Austroalpine nappes, Steinmann-Institut für Geologie, Mineralogie und Paläontologie, retrieved November 2015
The Adriatic or Apulian Plate is a small tectonic plate carrying primarily continental crust that broke away from the African plate along a large transform fault in the Cretaceous period. The name Adriatic Plate is usually used when referring to the part of the plate. This part of the plate was deformed during the Alpine orogeny, the Adriatic/Apulian Plate is thought to still move independently of the Eurasian Plate in NNE direction with a small component of counter-clockwise rotation. The fault zone that separates the two is the Periadriatic Seam that runs through the Alps, studies indicate that in addition to deforming, the Eurasian continental crust has actually subducted to some extent below the Adriatic/Apulian Plate, an unusual circumstance in plate tectonics. This subduction is responsible for the volcanics of southern Italy. The eastern Italian Peninsula, the part of Slovenia and the Adriatic Sea are on the Adriatic/Apulian Plate. Mesozoic sedimentary rocks deposited on the plate include the limestones that form the Southern Calcareous Alps
The theoretical model builds on the concept of continental drift developed during the first few decades of the 20th century. The geoscientific community accepted plate-tectonic theory after seafloor spreading was validated in the late 1950s, the lithosphere, which is the rigid outermost shell of a planet, is broken up into tectonic plates. The Earths lithosphere is composed of seven or eight major plates, where the plates meet, their relative motion determines the type of boundary, divergent, or transform. Earthquakes, volcanic activity, mountain-building, and oceanic trench formation occur along plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually, tectonic plates are composed of oceanic lithosphere and thicker continental lithosphere, each topped by its own kind of crust. Along convergent boundaries, subduction carries plates into the mantle, the material lost is balanced by the formation of new crust along divergent margins by seafloor spreading.
In this way, the surface of the lithosphere remains the same. This prediction of plate tectonics is referred to as the conveyor belt principle, earlier theories, since disproven, proposed gradual shrinking or gradual expansion of the globe. Tectonic plates are able to move because the Earths lithosphere has greater strength than the underlying asthenosphere. Lateral density variations in the result in convection. Plate movement is thought to be driven by a combination of the motion of the seafloor away from the ridge and drag, with downward suction. Another explanation lies in the different forces generated by forces of the Sun. The relative importance of each of these factors and their relationship to other is unclear. The outer layers of the Earth are divided into the lithosphere and asthenosphere and this is based on differences in mechanical properties and in the method for the transfer of heat. Mechanically, the lithosphere is cooler and more rigid, while the asthenosphere is hotter, in terms of heat transfer, the lithosphere loses heat by conduction, whereas the asthenosphere transfers heat by convection and has a nearly adiabatic temperature gradient.
The key principle of plate tectonics is that the lithosphere exists as separate and distinct tectonic plates, Plate motions range up to a typical 10–40 mm/year, to about 160 mm/year. The driving mechanism behind this movement is described below, tectonic lithosphere plates consist of lithospheric mantle overlain by either or both of two types of crustal material, oceanic crust and continental crust. Average oceanic lithosphere is typically 100 km thick, its thickness is a function of its age, as passes, it conductively cools
The mantle is a layer inside a terrestrial planet and some other rocky planetary bodies. For a mantle to form, the body must be large enough to have undergone the process of planetary differentiation by density. The mantle surrounds the planetary core, the mantle is surrounded by the crust. The terrestrial planets, the Moon, two of Jupiters moons and the asteroid Vesta each have a made of silicate rock. Interpretation of spacecraft data suggests that at least two moons of Jupiter, as well as Titan and Triton each have a mantle made of ice or other solid volatile substances. The interior of Earth, similar to the terrestrial planets, is divided into layers of different composition. The mantle is a layer between the crust and the outer core, Earths mantle is a silicate rocky shell with an average thickness of 2,886 kilometres. The mantle makes up about 84% of Earths volume and it is predominantly solid but in geological time it behaves as a very viscous fluid. The mantle encloses the hot core rich in iron and nickel, past episodes of melting and volcanism at the shallower levels of the mantle have produced a thin crust of crystallized melt products near the surface. A thin crust, the part of the lithosphere, surrounds the mantle and is about 5 to 75 km thick.
In some places under the ocean the mantle is exposed on the surface of Earth. The mantle is divided into sections which are based upon results from seismology and these layers are the following, the upper mantle, the transition zone, the lower mantle, and anomalous core–mantle boundary with a variable thickness. The uppermost mantle plus overlying crust are relatively rigid and form the lithosphere, below the lithosphere the upper mantle becomes notably more plastic. In some regions below the lithosphere, the shear velocity is reduced. Inge Lehmann discovered a seismic discontinuity at about 220 km depth, although this discontinuity has been found in other studies, the transition zone is an area of great complexity, it physically separates the upper and lower mantle. Very little is known about the lower mantle apart from that it appears to be relatively seismically homogeneous, the D layer at the core–mantle boundary separates the mantle from the core. A principal source of the heat that drives plate tectonics is the decay of uranium, thorium.
The mantle differs substantially from the crust in its properties as the direct consequence of the difference in composition
Apulia is a region of Italy in Southern Italy bordering the Adriatic Sea in the east, the Ionian Sea to the southeast, and the Strait of Òtranto and Gulf of Taranto in the south. Its southernmost portion, known as the Salento peninsula, forms a stiletto on the boot of Italy, the region comprises 19,345 square kilometers, and its population is about 4 million. It is bordered by the other Italian regions of Molise to the north, Campania to the west, across the Adriatic and Ionian Seas, it faces Albania, Bosnia-Herzegovina, Croatia and Montenegro, The Apulia region extends as far north as Monte Gargano. Puglias coastline is longer than any other mainland Italian region, in the north, the Gargano promontory extends out into the Adriatic, while in the south, the flat and dry Salento peninsula forms the heel of Italys boot. It is home to the Alta Murgia and Gargano National Parks, see also, History of Apulia Apulia is one of the richest archaeological regions in Italy. It was first colonized by Mycenaean Greeks, a number of castles were built in the area by Holy Roman Emperor Frederick II, including Castel del Monte, sometimes called the Crown of Apulia.
After 1282, when the island of Sicily was lost, Apulia was part of the Kingdom of Naples, as a result of the French–Spanish war of 1501–1504, Naples again came under the rule of Aragon and the Spanish Empire from 1504 to 1714. When Barbary pirates of North Africa sacked Vieste in 1554, they took an estimated 7,000 slaves, in 1861 the region became part of the Kingdom of Italy, with the new capital city at Turin. In the words of one historian, Turin was so far away that Otranto is today closer to seventeen foreign capitals than it is to Turin, the regions contribution to Italys gross value added was around 4. 6% in 2000, while its population was 7% of the total. The per capita GDP is low compared to the national average, in comparison with the country as a whole, the economy of Apulia is characterised by a greater emphasis on agriculture and services and a smaller part played by industry. In the last 20 years the base of the regions economy has changed radically. The majority of firms are financed by local capital.
In certain of these sectors – especially textiles, footwear, the region has a good network of roads but the railway network is somewhat inadequate, particularly in the south. Apulias 800 kilometers of coastline is studded with ports, which make this region an important terminal for transport and tourism to Greece, between 2007 and 2013 the economy of Apulia expanded more than that of the rest of southern Italy. Such growth, over decades, is a severe challenge to the hydrogeological system. Emigration from the depressed areas to northern Italy and the rest of Europe was very intense in the years between 1956 and 1971. Subsequently, the trend declined as economic conditions improved, to the point where there was net immigration in the years between 1982 and 1985, since 1986 the stagnation in employment has led to a new inversion of the trend, caused by a decrease in immigration. Since 1 June 2015, former judge and mayor of Bari Michele Emiliano of the Democratic Party has served as President, Apulia is divided into five administrative provinces and one metropolitan city, Cuisine plays an important role throughout Apulia
Geology of Andorra
Rocks from the Cambrian or Ordovician occur in the form of conglomerate, phyllite and slate. Diapirs of slate from the Silurian Period are found in the Llavirsi syncline near Bixessarri in the south west and schist are found in the cores of anticlines in the north east of the country. The antiforms are connected with near horizontal shear zones, containing nappes of metamorphosed sediments, younger overlying Paleozoic metamorphosed sediments found over most of Andorra have been steeply folded. In the south east of the country is an alkaline granite from a batholith called Mt-Louis-Andorra Batholith and it extends into Spain and covers an area of 600 km2. Different rock composition zones occur, with monzogranite found at the centre, quartz diorite at the edge, the batholith has caused metamorphism on its western edge. The base of the batholith is exposed in the east of Andorra, in the Central and Eastern Pyrenees, which includes Andorra, no fossils older than the Ordovician Caradoc 450–460 million years ago have been found.
Andorra has numerous glacial erosional features, including U-shaped valleys, cirques, arêtes, examples of cirques include the Cirque de Pessons in the east, Llac de Tristaina in the northwest, and the two cirques at approximately 2400 m elevation on Pic de Casamanya. Santa Coloma has a terminal moraine. Andorra by P. M. Oliver and E. M. Moores in Eldridge M. Moores, Rhodes Whitmore Fairbridge, Encyclopedia of European and Asian Regional Geology,1997 Springer, p.26. Berga 24 Mapa Geologico 1,200.000,1970, Instituto Geologico Y Minero de Espana