Category: Geography Notes PPT

India, the 7^th largest country in the world in terms of area, is the epitome of diversity. It is one of the best examples of diverse topography that can cite almost anything ranging from high-rise mountains and archipelagos. In this section, we will study the prime physical features of the India map. These features will be explained from the prehistoric age to the current geographical map we have seen. Learn the rich geographical features of India here and gather more knowledge to answer questions in your exams.

The Indian Map: A Brief Introduction

India is a country with remarkable topographical features that make it a great subject of study. You will be fascinated to learn that this country has almost every feature for a complete study of different geographical landforms. Ranging from the highest mountain ranges to plateaus, riverbeds to archipelagos, India is rich with such features. Read this section carefully and understand what points you can add to the physical features of India project.

The Origin of India

This is not a topic where you will find historical evidence of the empires and kingdoms. It goes way back to when the entire world had a single landmass divided into two massive segments. The Indian peninsula was a part of the Gondwana land segment. These segments formed due to the plate tectonic movements occurring beneath the sea level. The Indian peninsula was a part of the family that had Australia, South America, and South Africa as members.

The ocean currents and the tectonic actions separated these big landmasses and formed the continents. In fact, they are still moving apart from each other. It took millions of years to float apart from each other and to become a part of the big continents. The special features of India were drawn from the features of Gondwana Land. Some new features also evolved due to such movements of the tectonic plates and changes in the ocean currents.

The Indo-Australian tectonic plate(comprising the Indian peninsula and Australia) started moving north and eventually collided with the Eurasian Plate. This significant movement gave the country we are living in. If you follow the physical landscape of India, you will notice that the Himalayan ranges have formed as a barrier between the Eurasian Plate and the Indo-Australian plate. If you remember the features of the fold mountains, you will understand how the Himalayan Ranges formed due to the collision of these tectonic plates and the folding of the seabed to form a high-rise landscape. This is how India got her physical features. Let us now discuss these features elaborately.

Prime Physical Features of India Map

If you focus on the Indian map, you will find six different segments of physical features. These features are different from each other in terms of physical traits and formation.

1. The Himalayas

As mentioned earlier, the Himalayas are the prime feature of the Indian subcontinent. It is one of the prime physical characteristics of India that controls the climatic conditions of the entire northern part of the country.

The steepest and rugged mountain ranges in the world, the Himalayas stretch from Kashmir to Arunachal Pradesh. It covers almost 2500 km forming a protective arc. It stops the chilly Arctic winds from entering the landmass and keeps the tropical region warm. The width of this landmass ranges from 150 to 400 km. The average peak height is 6000 m in the Greater Himalayas. The same for the Lesser Himalayas is 4000 m.

Himalayan Ranges in Parallel

The Himalayas are made up of three parallel ranges that are split into three categories:

The ‘Himadri,’ or Great or Inner Himalayas: The Great Himalayas, which are perpetually snowbound, have the highest peaks. All of the main Himalayan peaks are included in the Himadri, which has an average height of 6,000 metres. It is one of India’s most visible physical characteristics.

Himachal or Smaller Himalaya: The lesser Himalaya or Himachal refers to the more difficult regions of the mountain range. Himachal Pradesh’s hill stations are also well-known. The average height of these ranges is 3700 to 4500 metres. The Pir Panjal range is the longest.

The Shiwaliks, or Outer Himalayan Range, are lower mountains with altitudes ranging from 900 to 1,100 metres. They are made up of unconsolidated sediments carried down by rivers from the Himalayan peaks.

Himalayan Regional Classification

The Himalayas are divided into regions.

The Himalayas are further separated into western and eastern regions:

• The Himalayan area between the Indus and the Satluj is known as the Punjab Himalaya, although it is also known as Kashmir and Himachal Himalaya in the west and east, respectively. 

• The Kumaon Himalayas are located between the Satluj and Kali rivers in Himalayas.

• The Nepal Himalayas are defined by the Kali and Tista rivers, whereas the Assam Himalayas are defined by the Tista and Dihang rivers.

• The Brahmaputra is the Himalayas’ easternmost frontier.

2. The Northern Plains

India has three main river systems made by the Ganga, Brahmaputra, and the Indus. It is the second most important physical feature of India on map. The rich alluvial deposit makes this place the cradle of civilization. The water flowing from the glacial origin of all these rivers helps civilizations to settle in their banks.

The Punjab plains cover the tributaries of Indus. A major part of this plain lies within the map of Pakistan. The Ganga Plains cover the states of West Bengal, Jharkhand, Bihar, Uttar Pradesh, Haryana, and North India. The Brahmaputra Plains cover Assam and a major part of the north-eastern states.

3. The Indian Peninsular Plateau

Considered as the oldest landform that dates back to the era of Gondwana Land, the Indian Peninsular plateau or the Deccan Plateau covers the Central Highlands ranging from Malwa Plateau to the northern part of the Narmada River. The rest of this landmass is the Deccan Plateau. It is a triangular landmass ranging from the Eastern Ghats to the Western Ghats.

4. The Indian Desert

The vast sand dunes in the arid western part of the country cover the Indian Desert. It ranges from the Aravali Hills to the western corridor of India covering the states of Rajasthan and North Gujarat.

5. The Indian Coastal Plains

The coastal plains of India are one of the major geographical features of India that ranges from the Bay of Bengal to the Indian Ocean and then to the Arabian Sea. The Arabian coastline is divided into the Konkan Coast, the Kannada Plains, and Malabar Coast. The Eastern Coast is divided into the Northern Circar and the Coromandel Coast.

6. Islands

India has two sets of archipelagos. The Andaman and Nicobar Islands, surrounded by the Bay of Bengal and the Indian Ocean, are in the east. The Lakshadweep archipelago lies in the west guarded by the Arabian Sea. It is considered to be one of the special features of India.

Physical Characteristics-Based Classification

The physical geographic elements of the Northern Plain also separate it. It is separated into four regions from north to south: Bhabar, Terai, Bangar, and Kadar.

Bhabar Region: It is located in the Himalayan foothills and is around 8-16 kilometres wide. The area is largely made up of stones and pebbles. The rivers are swiftly flowing here.

Terai: Terai is a 15-30 km broad region south of Bhabar. It is densely forested, and the land is suitable for farming. The water is moving quickly here.

Bangar Region: Located south of Terai, this region is less fertile.

Kadar Region: Located south of Bangar, Kadar is a rich, flood-prone region.

Conclusion

• Prime Geographical Features of the Map of India, the 7^th largest country in the world in terms of area, is the epitome of diversity.

• In this section, we will study the prime physical features of the India map.

• Learn the rich geographical features of India here and gather more knowledge to answer questions in your exams.

• The Indian Map: A Brief IntroductionIndia is a country with remarkable topographical features that make it a great subject of study.

• Read this section carefully and understand what points you can add to the physical features of the India project.

Pyrolusite mineral, essentially containing manganese dioxide is an important ore of manganese. It has a metallic luster, a black or bluish stream, and speedily tarnishes the fingers. The Pyrolusite is named from the Greek pyro and louein meaning “ fire” and “ to wash” because it was used to remove tints from glass. The specific gravity of Pyrolusite is 4.8. Pyrolusite mineral occurs associated with braunite, hollandite, manganite, goethite, hematite, and chalcophanite under highly oxidized conditions. It is minded in Germany, India, United States, Cuba, Ghana, Morocco, and South Africa. As an oxidizing agent, it is used in the preparation of chlorine.  Read the article below to get detailed information on Pyrolusite properties.  

Pyrolusite Physical Properties

Pyrolusite Ore Chemical Formula

The Pyrolusite ore chemical formula is MnO₂.

Pyrolusite

The Pyrolusite hardness ranges from 2- 6.5 on the moh scale.

Where is Pyrolusite Ore Found?

Pyrolusite ore is formed under high oxidizing conditions and high Ph.  As it is a mineral of shallow marine, bogs, and lacustrine, it is also found in an oxidized zone of magniferous deposits and deposits formed by circulating meteoric water.  Both bacteria action and colloidal processes are important in its formation. The leading producing countries of pyrolusite are India, Brazil, China, Russia, South Africa, and  Gabon.

Pyrolusite Uses 

• It is used in the manufacture of green and violet paints.

• It is used to prepare disinfectant and for decolorizing glass.

• As a coloring material, pyrolusite is used in calico printing and dyeing.

• It is used for imparting black, violet, and amber colors to glass, pottery, and bricks.

• It is extensively used in the preparation of various alloys such as manganese-bronze.

• As an oxidizing agent, pyrolusite is used in the preparation of chlorine. 

Pyrolusite Crystal Healing Properties

• The pyrolusite crystal protects the intention of those who populate the lower frequency of the Astral words and during ritual work.

• This gemstone strengthens the eyesight and treats bronchitis and walls of the blood veins.

• It defends against the diseases of constipation, colon, and bowels.

• It provides relief from pain, numbness, arthritis, and scalar tissue.

• It also treats the blood rate disorder and stimulates sexuality

• Pyrolusite crystal diminishes fear and aligns the chakras as well as auric body.

• Derived from the Greek “ fire wash”, the pyrolusite is a stone of purification.

• It offers support during emotional healing, and also releases blockage and stabilized relationships.

• The stone promotes confidence, optimism, and determination.

• The stone drives off the negative power, evil, and dispels all the physical attacks.

Pyrolusite Metaphysical Properties

• Pyrolusite transforms negative expectations and thoughts into positive ones.

• It stabilizes relationships.

• The stone has the power to transfer and restructure the powers.

• The stone contains every possible color to heal the aura of the body. 

• By raising a person with strong will determination, also enhances mental clarity.

• It is also known as the stone of transformation as it is used to undue mental influence.

• The gemstone helps one to be truthful to their beliefs and remove interference.   

• The gemstone helps someone in promoting a strong determination.

Did You Know?

• Pyrolusite is a mineral essentially containing manganese dioxide(MnO₂)

• Romanechite and pyrolusite are the most important manganese minerals. 

• The mineral is obtained by reduction of the oxide with magnesium, sodium, aluminum, and electrolysis. 

• Pyrolusite is widely used in the manufacture of various manganese-bronze alloys.

• It forms in stagnant shallow marine and freshwater bogs along with swamp deposits.

• Pyrolusite is derived from the Greek “ fire wash” as it is used to remove stains from the glass.

• Pyrolusite is also formed as direct deposits from cold groundwater in bogs and on the ocean floor. 

Rossby waves are a type of initial oscillations occurring naturally in rotating fluids. Rossby waves, also known as planetary waves are first observed by Carl-Gustaf Arvid Rossby.  The waves are observed in the atmosphere and oceans of planets because of the rotation of planets. 

Atmospheric Rossby waves are massive meanders in high altitudes that have a significant impact on weather. These waves are related to the jet stream and pressure system. Oceanic Rossby waiver moves along the boundary between the warm upper layer and the cold deep part of the ocean. 

Rossby Waves Definition

Rossby waves, also known as planetary waves are massive meanders in high altitudes that have a major effect on weather. The emergence of Rossby waves is due to shear in the rotating fluid so that the Coriolis force varies along the sheared coordinate. In the Planetary atmosphere, the emergence of the Rossby wave is due to changes in the Coriolis effect with latitude. 

Rossby Waves Formation

Rossby waves are formed when tropical air is moving poleward and polar air moves towards the equator. Because of the difference in temperature between the Equator and the poles due to the difference in the amount of solar radiation received, heat tends to flow from low to high latitudes. This is attained in part, by these air movements. 

• Rossby waves are the principal component of the Ferrel circulation. The heat is transferred to the poleward by the tropical waves and polar air absorbs heat as it moves toward the equator.

• The existence of the Rossby waves explains cyclones and anticyclones.

Rossby Number

Rossby number, also known as Kibel number is a dimensionless number used for measuring liquid. It is the ratio of inertial force to Crosiloses force for a given flow of rotating liquid. Rossby number is commonly used in the geographical phenomena in the atmosphere and ocean, where it features the importance of Coriolis acceleration, originating from planetary rotation.

Rossby Number is Defined as the:

Rₒ = [frac{U}{Lf}]

In the above equation, U is the velocity scale, f is the Coriolis parameter, and L is the horizontal length scale.

Types of Rossby Waves

The Different Types of Rossby Waves are:

• Atmospheric Rossby Waves

• Oceanic Rossby Waves

• Topographic Rossby Waves

Atmospheric Rossby Waves

Atmospheric Rossby waves primarily result from the conservation of potential vorticity and are affected by the Coriolis force and pressure gradient.  The rotation causes fluid to move towards the right as they move in the  Northern hemisphere and to the left as they move in the Southern hemisphere. For example, a fluid moving from the equator toward the north pole will deviate towards the east whereas the fluid movie moving from the north towards the equations will deviate towards the west. 

These deviations are generated by Coriolis force and conservation of potential vorticity which gives rise to change in relative vorticity. This is similar to the conservation of angular momentum in the mechanism.  In the Planetary atmosphere, including Earth, the Rossby waves are caused due to changes in the Coriolis effect with latitude.

Oceanic Rossby Waves

Oceanic Rossby waves are wide-reaching waves found within an ocean basin. In comparison to the Atmospheric Rossby waves which are in the order of hundreds of kilometers, the oceanic Rossby waves are in the order of centimeters ( at the surface)  to meters (at thermocline).  The waves may take months to cross an ocean basin. 

The Oceanic Rossby waves are so large and massive that they can change the Earth’s climatic conditions. The waves gain momentum from the wind stress at the ocean surface layer and are thought to communicate climate changes because of the variability in forcing and due to both the wind and buoyancy. Satellite observations have approved the emergence of Oceanic Rossby waves. 

Jet Stream and Rossby Waves

A Jet stream is defined as a current of fast-moving air that is generally several thousand miles ago and is relatively thin. The jet streams are found in the upper layer of the atmosphere at the tropopause- the boundary between the stratosphere and the troposphere. 

Jet streams are important because they provide the worldwide weather pattern and help meteorologists to forecast weather based on their position. Also, they are important to air travel because flying in or out can minimize flight time and fuel consumption. 

The meandering or whirl movement of the jet stream is known as Rossby waves.  The Rossby waves were first observed by Carl- Gustaf Arvid Rossby.

Did You Know?

• Rossby waves, also known as planetary waves, are naturally occurring waves in rotating fluid. 

• The terms baroclinic and barotropic are used to describe Rossby waves’ vertical structure.

• Rossby waves in Earth’s atmosphere are easy to observe large-scale meanders of the Jet stream.

• Atmospheric Rossby waves, similar to Kelvin waves can occur on any rotating planet with an atmosphere. The Y-shaped characteristics of clouds on Venus are credited to Kelvin and Rossby waves.

The concept of sedimentary facies depicts that the sedimentary facies are actually the bodies of sediment recognizably distinct from adjacent sediment accumulated in a different depositional environment. As conditions alter with time, so various depositional sites may also their shapes and characteristics.

Usually, facies are differentiated by the aspect of the rock or sediment that is being studied. Therefore, facies based on petrological characters such as mineralogy and grain size are referred to as lithofacies, whereas facies based on fossil content are known as biofacies.

Types of Sedimentary Facies

Sedimentary facies indicate a depositional environment, each facies being a distinct type of sediment for that area or environment. Thus, there are various ways of describing or designating sedimentary facies. Taking into account the principal physical (or lithological) characteristics, one is able to identify lithofacies. The biological (or more appropriately, paleontological) characteristics—the fossils—describe biofacies. It is quite usual to speak of alluvial facies, bar facies, or reef facies, considering the environment as a criterion.

Facies under coal, clay, shale, and sandstone may be repeated several times and are known as cyclothems. Rhythmic or cyclic sedimentation has been documented in various rocks in different parts of the world and may occur in various ways; however, re-assessment of many successions originally defined as cyclic displays that this phenomenon is not as common or as consistent as had been thought of.

Sedimentary Facies Analysis

Talking about the Sedimentary facies and reservoir characteristics and analysis, we will undertake the 8 sandstones. This sandstone is a unit in the Western Sulige field which is one of the most prolific gas‐generating intervals in the Ordos Basin.

Purpose of Sedimentary Facies Analysis

Sedimentology and reservoir characteristics analysis are basically undertaken in order to interrogate the reservoir’s petrological, petrophysical, diagenetic properties, and production features. Three types of sandstone and four types of lithofacies were identified. The two frequently seen lithofacies are labelled lithofacies C and D.

Lithofacies C is made up of fine‐ to medium‐grained litharenite (Sandstone I); lithofacies D composed of coarse‐grained sublitharenite (Sandstone II) and coarse‐grained/gravelly litharenite (Sandstone III).

Results of Sedimentary Facies Analysis

In comparison, Lithofacies C, Lithofacies D was accumulated as a series of overlaying sand sheets in a greater energy fluvial system. The firmness of Sandstone I is an outcome of an event of intense compaction of the rock substructure giving rise to early dissolution of grains and deformation of ductile rock splinters. The mechanisms that resulted in the low permeability of Sandstone II and Sandstone III are more complicated. Moreover, intense compaction, the development and emplacement of quartz and clay cements plays a critical factor. Besides these,

• Evolution of Diagenesis and porosity assessment exhibits that the petrophysical properties of these sandstones were better at the gas charging time.

• The permeability and porosity values of Sandstones II and III are same at the surface, but considerably different at formation pressure. This causes differences in gas production rates.

• Sandstone II possesses greater gas production rates and cumulative gas production than Sandstone III.

• The presence or absence of Sandstone II monitors and curbs the dispersion of sweet spots within less productive tight gas reservoirs.

Fun Facts

• The suite of structures actually develops facies.

• Sedimentary facies are either terrigenous, emancipating from the deposits of particles weathered from older rocks and carried to the depositional site; biogenic, depicting depositions of whole or broken shells and other hard parts of organisms; or chemical, depicting inorganic precipitation of substance from a solution.

• Each facies consists of a three-dimensional configuration and overtime shifts its position.

• A facies (Latin terms used for appearance or aspect) is a body of rock (i.e. a series of beds) or sediment marked by a specific combination of compositional, biological and physical structures that differentiate it from bodies of rock/sediment.

• A sedimentary facies contains a set of properties that makes it distinctive, which the geologist defines.

• In general, facies are described based on a suite of characteristics in rocks/sediment.

India is the ancient civilization in the world. It has displayed remarkable progress in many fields such as agriculture, technology, economic development, and industry and has contributed forward in the making of world history. 

India is located in the Northern hemisphere. By land area, it is the seventh-largest country and the most populous democracy in the world. Bounded by the Indian Ocean, The Arabian Sea, and the Bay Of Bengal. It shares its land borders with Pakistan, China, Nepal, Bhutan, Bangladesh, and Myanmar. The following points will discuss more about its location:

1. The land extends between latitude 8°4’N and 37°6’N and longitudes 68°7’E and 97°25’E.

2. The Tropic Of Cancer divides India into two equal parts.

Size of India

It is the seventh-largest country in the world covering a total area of 3,287,263 square kilometres. It has a land frontier of 15200 km and a coastline that covers 7516.6 km. The following points discuss more about the landmark.

1. India is covered by mountains in the northwest, north, and northeast.

2. The landmark begins to taper and extends towards the Indian Ocean, dividing into two seas. The Arabian Sea on the west and the Bay Of Bengal on the east.

3. Time along the Standard Meridian of India is taken as the standard time zone of India. 

4. The Standard Meridian passes through Mirzapur in Uttar Pradesh (82°30’E)

India and the World

The Indian landmark is centrally located between west and east Asia. The countries in the west and east are connected through trans-Indian routes. India enjoys its contacts with the world via land routes more than maritime contacts and is the only nation that has an ocean named after it ( Indian Ocean )

India has contributed a lot to the world in the forms of philosophies and mathematics. Philosophies include Upanishads, Panchtantra, and Ramayana Mahabharat. Mathematics contributions include Indian numerals and decimal systems.

Due to various contributions to the outside territory, India’s architecture was influenced by Greek sculpture and architectural styles of West India.

India’s Neighbours

India occupies an important position in South Asia and has 29 States and 7 Union Territories. Its boundaries are shared with Pakistan, Afghanistan, Bhutan, Myanmar, Bangladesh, and China. The southern neighbours across the sea consist of two island countries, namely the Maldives and Sri Lanka. 

Sri Lanka and India are separated by Pak Strait, a narrow strip of sea. India stands apart from the rest of Asia and always has had strong geographical and historical links with its neighbours.

Climate 

India hosts 6 major climatic conditions ranging from the arid desert, glaciers, humid tropicals, and alpine tundra. The Himalayas act as a barrier from Central Asia. Due to this northern India is kept warm or mildly cool during winters. In summers, it is relatively hot. The Tropic Of Cancer – the boundary between tropics and subtropics passes through the middle of India and the whole country is considered to be tropical. It governs a tropical rainy climate in some regions with persistent warm or high temperatures. Also here a tropical wet and dry climate is more common.

Summers last between March and June. The rain-bearing monsoon clouds are attracted to the low-pressure system. The southwest monsoon diverges into two parts, the Bay Of Bengal and the Arabian Sea. Winters in the peninsula experience mild to warm days and cool nights. Temperatures in some parts fall below freezing. Most of the northern part of India is plagued by fog during the season. The highest temperature being recorded in India is 51 degrees in Phalodi ( Rajasthan ) Celcius and the lowest temperature being recorded is -60 degrees Celcius in Dras ( Jammu and Kashmir )

Earth as we know Is the 3rd planet in the solar system. The solar system is a system of planets wherein all the planets, 8 to be precise revolve around the giant ball of fire, the sun. All these 8 planets revolve around the sun in an orderly manner and always follow the same trajectory. The trajectory or path followed by every planet is known as its orbit. Every planet has a different orbit. These orbits aren’t circular in shape, in fact, they are elliptical. The radius of orbits varies and the increase in the radius results in the arrangement of the planets in an orderly manner. 

What are the Two Motions of the Earth? 

As we just learned, every planet revolves around the sun in a specific orbit. So does our planet. Our planet revolves around the sun with a period of 365.25 days. Likewise, every other planet has a time period of its own, this time period increases as the distance from the sun increases. Revolution, however, is just one of the motions executed by our planet, earth. Our planet also rotates on its own imaginary axis. Both of these motions happen together, the earth revolves and rotates simultaneously. 

Rotation of the Earth

The earth rotates about its tilted imaginary axis from West to east. The time period for this rotation is 24 hours. That means the earth completes one full rotation after every 24 hours. So your net displacement after 24 hours will be 0. If viewed from the pole star, the earth appears to rotate counterclockwise. 

Some History About the Discovery of Rotation of Earth

Some of the scholars in 470 BC believed that the rotation of the earth is just an apparent thing and in reality is just an illusion. However, it was for the first time in 499 BC, Aryabhatta, an Indian scientist stated that the earth rotates about a fixed axis daily. Soon the statement spread to the west and western philosophers started believing that the earth does rotate about a fixed axis. 

Revolution of Earth Around the Sun 

Revolution is the second phenomenon executed by the earth. The earth goes around the sun in an elliptical orbit every 365.25 days, this periodic motion of the earth is called a revolution. The earth’s orbit is an eclipse and the earth-sun barycenter is one of the focuses of this ellipse. The eccentricity of the ellipse is 0.0167. Ever wondered why the earth revolves around the sun? Well, if not then let’s find the answer out today! 

Why Does the Earth Revolve Around the Sun? 

Why does the earth have to revolve around the sun? Well, this is because the sun has a huge mass. It’s a lot greater than the mass of earth or any other planet in the solar system. Sun is the biggest body in our solar system and hence it has the highest gravitational force. Gravitational force is the force between two bodies that is dependent on the masses of both bodies. The higher is the mass, the stronger is the gravitational pull. Hence, the sun being the heaviest controls the motion of all the other planets in the solar system. 

Some Numbers That Will Take You By Surprise! 

The History Behind the Discovery of Revolution

Heliocentrism is the first-ever model which was designed according to the theory which said that the sun is at the center of the solar system. Until then, the theory of geocentrism was believed according to which the earth was the center of the solar system. Soon Copernicus came up with his theory of a static center, that is the sun. And all the planets moved around this static center In fixed orbits. Then, experiments were conducted to prove the theory and soon the world started believing the theory of heliocentrism. 

Fun Fact: 

The earth’s rotation period is reducing with each passing day. This means that days in the past were longer than days today. Well, this isn’t just a joke and has scientific backing to it. The earth’s rotation period is known to be decreasing as we progress forward in time. This is due to the moon’s tidal effect. According to some experiments conducted by a few learned scientists, a day today is almost 1.7 milliseconds lesser than a day, one century ago. Although, the time lag is not much, with time this shall definitely increase.