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Yogita Ingle 1 day, 10 hours ago

  • Cataclastic metamorphism occurs along with the tectonic plate faults where the rocks get rubbed with each other which results in the grain size reduction.
  • Transformation of these rocks are classified as one which could not form non foliated rock and is of low grade.
  • Circulation of rock results in huge number of mineral water chemical reactions which results in different kinds of precious metals and stones.
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Gaurav Seth 1 day, 11 hours ago

Answer: The oceanic crust is layer of earth is also known as sima
The oceanic crust is called ‘sima’. The root of the word sima is ‘si’ from silica and ‘ma’ from magnesium.

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Gaurav Seth 2 days, 8 hours ago

• Seafloor spreading is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.

• Seafloor spreading helps explain continental drift in the theory of plate tectonics.

• This theory was proposed by Hess in 1961. He argued that constant eruptions at the crest of oceanic ridges cause the rupture of the oceanic crust and the new lava wedges into it, pushing the oceanic crust on either side. Thus,the ocean floor spreads.

• The younger age of the oceanic crust as well as the fact that the spreading of one ocean does not cause the shrinking of the other, made Hess think about the consumption of the oceanic crust.

• He further maintained that the ocean floor that gets pushed due to volcanic eruptions at the crest, sinks down at the oceanic trenches and gets consumed.

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Shivam Dixit 4 hours ago

Wheat

Yogita Ingle 2 days, 13 hours ago

Rabi crops are known as winter crops. They are grown in October or November. The crops are then harvested in spring. These crops require frequent irrigation because these are grown in dry areas. Wheat, gram, barley are some of the rabi crops grown in India.

Examples of Rabi Crops

Following are some of the examples of rabi crops:

  • Wheat
  • Barley
  • Oats
  • Pulses
  • Mustard
  • Linseed
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Yogita Ingle 4 days, 3 hours ago

The metamorphic rocks make up a large part of the Earth’s crust and are classified by texture and by chemical and mineral assemblage. They may be formed simply by being deep beneath the Earth’s surface, subjected to high temperatures and the great pressure of the rock layers above it.

Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means “change in form”. The original rock is subjected to heat with temperatures greater than 150 to 200°C and pressure around 1500 bars, causing profound physical and/or chemical change.

Gaurav Seth 4 days, 3 hours ago

 metamorphic rock is a type of rock which has been changed by extreme heat and pressure.


The types of metamorphic rocks depend upon the original rocks that were subjected to metamorphism. Metamorphic rocks are classified into two major types:

(i)foliated rocks 


(ii)non-foliated rocks

Formation of metamorphic rocks : These rocks are formed due to thermal metamorphism.

It is of two types :

(i)Contact metamorphism: In contact metamorphism the rocks come into the contact with hot magma and lava and the rock material is recrystallized under high pressure and temperature.


(ii)Regional metamorphism: In regional metamorphism, rocks under go recrystallization due to deformation caused by tectonic shearing together with high temperature or pressure or both.

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Yogita Ingle 4 days, 3 hours ago

The sedimentary rocks are formed by the deposition and subsequent cementation of that material within bodies of water and at the surface of the earth. The process that causes various organic materials and minerals to settle in a place is termed as sedimentation. Sedimentation may also occur as minerals precipitate from water solution or shells of aquatic creatures settle out of suspension.

Gaurav Seth 4 days, 3 hours ago

Sedimentary rocks are types of rock that are formed by the deposition and subsequent cementation of that material at the Earth's surface and within bodies of water.

 

Sedimentary rocks are formed from those materials which are deposited at favourable sites by agents of denudation such as river, wind, glacier and sea waves. The process is called the lithification.

The sedimentary rocks are formed in different ways.

(i)The layers of deposits : Loose materials or sediments are deposited in the layers.

(ii)Stratification : The sediments are deposited in the layers. Materials such as clay, silt, sand, etc. settle down in due course.


(iii)Solidification: The loose material gets converted into hard and compact rocks.

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Yogita Ingle 4 days, 3 hours ago

 Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can be derived from partial melts of existing rocks in either a planet’s 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.

Gaurav Seth 4 days, 3 hours ago

Igneous rocks are those rocks which have been formed by the cooling and solidification of molten natural matter of the earth.



The igneous rocks are formed when magma cools and turns into solid forms. The process of the cooling and solidification can happen in the earth's crust as well as on the surface.

Characteristics of igneous rocks are described below :

(i)These rocks do not have particles and layers.

(ii)These rocks are compact and massive.

(iii)These rocks are crystalline.

(iv)The igneous rocks are extremely hard and resistant.

(v)These rocks do not possess fossils of plants or animals.

(vi)These rocks are thermal in origin.

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Yogita Ingle 4 days, 3 hours ago

The rock cycle is a process in which rocks are continuously transformed between the three rock types igneous, sedimentary and metamorphic.

Gaurav Seth 4 days, 3 hours ago

 

Rock Cycle

The process of transformation of rocks from one form to an other in a cyclic manner is known as the rock cycle. It includes the following processes:

  • Hot lava cools down to form igneous rocks.
  • These igneous rocks are then broken down into small particles which are transported and then deposited. This results in the formation of sedimentary rocks
  • When these igneous and sedimentary rocks are subjected to great heat and pressure, they change into metamorphic rocks.
  • These metamorphic rocks under heat and pressure breakdown and form hot lava.
  • This hot magma then again cools down and forms igneous rocks.
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Gaurav Seth 4 days, 3 hours ago

Followings are the physical characteristics of minerals:

(i)External crystal form — determined by internal arrangement of the molecules — cubes, octahedrons, hexagonal prisms, etc.

(ii)Cleavage — tendency to break in given directions producing relatively plane surfaces — result of internal arrangement of the molecules — may cleave in one or more directions and at any angle to each other.

(iii)Fracture — internal molecular arrangement so complex there are no planes of molecules; the crystal will break in an irregular manner, not along planes of cleavage.

(iv)Lustre — appearance of a material without regard to colour; each mineral has a distinctive lustre like metallic, silky, glossy etc.

(v)Colour — some minerals have characteristic colour determined by their molecular structure — malachite, azurite, chalcopyrite etc., and some minerals are coloured by impurities. For example, because of impurities quartz may be white, green, red, yellow etc.

Yogita Ingle 4 days, 3 hours ago

Followings are the physical characteristics of minerals:

(i)External crystal form — determined by internal arrangement of the molecules — cubes, octahedrons, hexagonal prisms, etc.

(ii)Cleavage — tendency to break in given directions producing relatively plane surfaces — result of internal arrangement of the molecules — may cleave in one or more directions and at any angle to each other.

(iii)Fracture — internal molecular arrangement so complex there are no planes of molecules; the crystal will break in an irregular manner, not along planes of cleavage.

(iv)Lustre — appearance of a material without regard to colour; each mineral has a distinctive lustre like metallic, silky, glossy etc.

(v)Colour — some minerals have characteristic colour determined by their molecular structure — malachite, azurite, chalcopyrite etc., and some minerals are coloured by impurities. For example, because of impurities quartz may be white, green, red, yellow etc.

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Gaurav Seth 4 days, 3 hours ago

Seafloor spreading is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.

• Seafloor spreading helps explain continental drift in the theory of plate tectonics.

• This theory was proposed by Hess in 1961. He argued that constant eruptions at the crest of oceanic ridges cause the rupture of the oceanic crust and the new lava wedges into it, pushing the oceanic crust on either side. Thus,the ocean floor spreads.

• The younger age of the oceanic crust as well as the fact that the spreading of one ocean does not cause the shrinking of the other, made Hess think about the consumption of the oceanic crust.

• He further maintained that the ocean floor that gets pushed due to volcanic eruptions at the crest, sinks down at the oceanic trenches and gets consumed.

Yogita Ingle 4 days, 3 hours ago

SEA FLOOR SPREADING
1 .it was proposed by Hess in 1961
2. he believed that new lava pushes out the plates from the mid-oceanic ridge
3. palaeomagnetic studies of the ocean floor reveal that
A. along the mid-oceanic ridge there is an intense volcanic eruption
B. huge amount of lava comes out along the mid-Atlantic ridges
C. the equidistant rock formations have similar age and chemical compositions & magnetic properties
7. rocks closer to the mid-oceanic ridges are young and normal polarity
8. The age of rocks increases as the distance increases from the mid-oceanic ridge
9. Oceanic crust is much younger(200my) than continental crust (3200my)
10. The sediments of ocean floor is very thin

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Gaurav Seth 4 days, 3 hours ago

Plate tectonics affects humans in several important ways.

  • It causes earthquakes
  • It causes volcanism
  • It induces recycling of elements within the biosphere and between the geosphere and biosphere
  • It causes mountain-building

Types of plate boundaries:

Plate Boundaries mainly consists of three types (fourth is a mixed type), formed in the manner the plates shift in relative to each other. These are collectively referred to as surface phenomena of different types. Plate boundaries are of different types, namely:

Transform boundaries:

These boundaries happen where two lithospheric plates move apart, or maybe further precisely, collide away from one other despite the transform faults, where plates are neither created nor destroyed.

Divergent boundaries:

These boundaries happen when both plates move apart from one other.

Convergent boundaries:

These boundaries happen where both plates move towards one other to form a zone of subduction or a continental collision.

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Yogita Ingle 4 days, 2 hours ago

The forces were:

(i)Pole fleeing force
(ii)Tidal force

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Yogita Ingle 4 days, 5 hours ago

The convectional currents in the mantle are generated due to radioactive elements causing thermal differences in the mantle portion. The currents move in radial direction and develop in cell patterns.

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Yogita Ingle 4 days, 5 hours ago

Drift Theory :
(i)Continental drift theory by Wegener assumes all the present continents to have arisen by the breaking and then drifting of the components of the Super - continent Pangaea.
(ii)Continental drift theory only considers the horizontal movement.
(iii)Continental drift theory mostly relies on circumstantial evidences of Jig-Saw-Fit, fossils, place deposits etc.
(iv) Continental drift theory relies on the concept of plate tectonics to be validated.
Plate Tectonics :
(i)Plate Tectonics assumes the whole earth’s lithosphere  to be divided into different ‘major’ and ‘minor’ plates which are constantly moving.
(ii)Plate tectonics takes into account the subduction of plates also.
(iii)Plate tectonics is based on scientific analysis of the processes inside the earth’s surface.

(iv)Plate tectonic theory validates the drift theory and is not to be validated by the same.

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Yogita Ingle 4 days, 5 hours ago

Plate tectonics is the theory that Earth’s outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. The plates act like a hard and rigid shell compared to Earth’s mantle. This strong outer layer is called the lithosphere.

The earth’s lithosphere is composed of seven or eight major plates and many minor plates. The lithosphere is a rigid outermost shell of earth and is broken up into tectonic plates. When these plates meet, their relative motion determines the type of boundary like convergent, divergent, or transform.

Volcanic activity, earthquakes, mountain-building, and oceanic trench formation occur along these plate boundaries. The relative movement of the plates typically ranges from zero to 100 mm annually.

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Yogita Ingle 4 days, 5 hours ago

  • Continental drift theory was proposed by Alfred Wegener in 1912.
  • It was first put forward by Abraham Ortelius in 1596 before fully being developed by Alfred Wegener.
  • The theory deals with the distribution of the oceans and the continents.
  • According to Wegener’s Continental Drift theory, all the continents were one single continental mass (called a Super Continent) – Pangaea and a Mega Ocean surrounded this supercontinent. The mega ocean is known by the name Panthalassa.
  • Although Wegener’s initial theory did not cover mantle convection until Arthur Holmes later proposed the theory.
  • The supercontinent was named Pangaea (Pangea) and the Mega-ocean was called Panthalassa.
  • According to this theory, the supercontinent, Pangaea, began to split some two hundred million years back.
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Yogita Ingle 4 days, 5 hours ago

Convergent boundary
1.When two plates move towards each other they are called converging.
2.Convergence of two plate boundaries leads to the folding of land and formation of mountains.
3.When they converge, subduction takes place and lithosphere is being consumed.Hence it is also called as destructive plate boundaries.

Divergent boundary
1.When two plates move away from each other they are called diverging.
2.Divergence of two plate boundaries causes the fracture in landforms.
3.When they diverge, new lithosphere is being formed by accretion.Hence it is also called as constructive plate boundaries..

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Yogita Ingle 5 days, 8 hours ago

Catchment of small rivulets and rills are often referred to as watersheds. Watersheds are smaller in area.

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Aruneel Baghel 4 days, 10 hours ago

Gulf and bay are both large bodies of water, but gulf is considered to be larger than a bay. Although a bay in itself is a wider body of water.
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Meghna Thapar 6 days ago

A strait is a narrow body of water that connects two larger bodies of water. It may be formed by a fracture in an isthmus, a narrow body of land that connects two bodies of water. The definition of a strait is a difficulty or a hard situation. An example of a strait is a poor family being in “dire straits.” Strait is narrow waterway between two larger bodies of water. An example of a strait is the Bering Strait. A strait is a narrow passage of water which connects two large water bodies.

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Meghna Thapar 6 days ago

India's having Long coastline is boon as well as bane also but it can be short out by some policies
India's coastline is roughly 7,500 km on West Arabian sea and Bay of Bengal in East this long coastline provides India large advantages
1) maritime trade - allows India to trade most of the world countries
2) tourism - a long coastline is very well known for tourism e.g, TN,Kerala, Goa
3) low cost of imports and exports - through sea transport it's cheaper than land
4) monsoon - swm is also known as real finance minister of India , good amount of rainfall
5) safety - from land sea coastline is considered as more safer
6) resources - India's largely dependent on the sea for fishing and India is the largest fishing industry
Some bane's are
1) disaster - Indian ocean is prone to tsunami
2) security terrorist activities, smuggling, trafficking,illegal fishing
3) piracy - from Somalian region many hijacking of ships
4) naval competition

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Meghna Thapar 6 days, 1 hour ago

A diagram is a symbolic representation of information using visualization techniques. Diagrams have been used since ancient times on walls of caves , but became more prevalent during the Enlightenment. Sometimes, the technique uses a three-dimensional visualization which is then projected onto a two-dimensional surface. The word graph is sometimes used as a synonym for diagram.

The term "diagram" in its commonly used sense can have a general or specific meaning:

visual information device : Like the term "illustration", "diagram" is used as a collective term standing for the whole class of technical genres, including graphs, technical drawings and tables.

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Yogita Ingle 6 days, 2 hours ago

Pangaea formed through a gradual process spanning a few hundred million years. Beginning about 480 million years ago, a continent called Laurentia, which includes parts of North America, merged with several other micro-continents to form Euramerica. Euramerica eventually collided with Gondwana, another supercontinent that included Africa, Australia, South America and the Indian subcontinent.

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Yogita Ingle 6 days, 2 hours ago

Earth crust is the thinnest and the most rudimentary layer that makes up the Earth, and yet, everything that has ever lived on Earth has called it home. The crust is a dynamic structure and it is one of the layers that make up our pale blue dot. The crust is referred to as a chemical layer that has varying chemical compositions. 

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Meghna Thapar 6 days ago

The temperature within the Earth is very high, because it has very much humidity, hot lava. This causes the rocks also becomes hot called magma. There are three main sources of heat in the deep earth: (1) heat from when the planet formed and accreted, which has not yet been lost; (2) frictional heating, caused by denser core material sinking to the center of the planet; and (3) heat from the decay of radioactive elements.

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Meghna Thapar 6 days ago

When we go inside the earth a pressure is exerted because of the gas particles in the air—like particles of all fluids—are constantly moving and bumping into things, they exert pressure. The pressure exerted by the air in the atmosphere is greater close to Earth's surface and decreases as you go higher above the surface.

The pressure in the Earth's inner core is slightly higher than it is at the boundary between the outer and inner cores: it ranges from about 330 to 360 gigapascals.

Pressure also increases in the outer core due in part to the weight of the crust and mantle above. The Earth's magnetic field is generated by the outer core.

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