PHYSICAL FEATURES OF INDIA:MAJOR PHYSIOGRAPHIC DIVISIONS

The physical features of India can be grouped under the following physiographic divisions:
(1) The Himalayan Mountains
(2) The Northern Plains
(3) The Peninsular Plateau
(4) The Indian Desert
(5) The Coastal Plains
(6) The Islands
The Himalayan Mountains:

The Himalayas, geologically young and structurally fold mountains stretch over the northern borders of India. These mountain ranges run in a west-east direction from the Indus to the Brahmaputra. The Himalayas represent the loftiest and one of the most rugged mountain barriers of the world. They
form an arc, which covers a distance of about 2,400 Km. Their width varies from 400 Km in Kashmir to 150 Km in Arunachal Pradesh. The altitudinal variations are greater in the eastern half than those in the western half. The Himalaya consists of three parallel ranges in its longitudinal extent. A number of valleys lie between these ranges. The northern most range is known as the Great or Inner Himalayas or the ‘Himadri’.It is the most continuous range consisting of the loftiest peaks with an average height of 6,000 metres. It contains all the prominent Himalayan peaks.
The folds of Great Himalayas are asymmetrical in nature. The core of this part of Himalayas is composed of granite. It is perennially snow bound, and a number of glaciers descend from this range.
The range lying to the south of the Himadri forms the most rugged mountain system and is known as Himachal or lesser Himalaya. The ranges are mainly composed of highly compressed and altered rocks. The altitude varies between 3,700 and 4,500 metres and the average width is of 50 Km. While the Pir Panjal range forms the longest and the most important range, the Dhaula Dhar and the
Mahabharat ranges are also prominent ones.

PHYSICAL FEATURES OF INDIA

India has practically all major physical features of the earth i.e. mountains, plains, deserts, plateaus and islands.We find different types of rocks; some are very hard like marble which has been used for
making the Taj Mahal, and some are very soft like soap stone which is used in making talcum powder. The colour of soil varies from one place to the other because soil is formed out of different types of rocks. Have you ever thought about the causes of these variations? Most of these variations are caused due to differences in rock formations.
India is a large landmass formed during different geological periods which has influenced her relief. Besides geological formations, a number of processes such as weathering, erosion and deposition have created and modified the relief to its present form.
Earth scientists have attempted to explain the formation of physical features with the help of some theories based on certain evidences. One such plausible theory is the “Theory of Plate Tectonics”. According to this theory, the crust (upper part) of the earth has been formed out of seven major and some minor plates.(Tectonic plates)

The movement of the plates results in the building up of stresses within the plates and the continental rocks above, leading to folding, faulting and volcanic activity. Broadly, these plate movements are classified into three types. While some plates come towards each other and form convergent boundary. Some plates move away from each other and form divergent boundary. In the event of two plates coming together they may either collide and crumble, or one may slide under the other. At times, they may also move horizontally past  each other and form transform boundary. The movement of these plates have changed the position and size of the continents over millions of years. Such movements have also influenced the evolution of the present landform features of India.


The oldest land mass of India (peninsula part)was the part of Gondwana land. Gondwana included most of the landmasses in today's Southern Hemisphere, including Antarctica, South America, Africa, Madagascar, and the Australian continent, as well as the Arabian Peninsula and the Indian Subcontinent, which have now moved entirely into the Northern Hemisphere.The conventional currents split the crust in the number of pieces thus leading to the drifting of the Indo-Australian plate after being separated
from the Gondwana land, towards north. The northward drift resulted in the collision of the plate
with the much larger Eurasian Plate. Due to this collision, the sedimentary rocks which were
accumulated in the geosyncline known as the Tethys were folded to form the mountain system
of western Asia and Himalaya.
The Himalayan uplift of Tethis sea and subsidence of northern flank of peninsular plateau reasulted in the formation of a large basin. In due course of time this depression, gradually got filled with deposition of sediments by the rivers flowing from the mountains in the north and the peninsular plateau in the south. A flat land of extensive alluvial deposits led to the formation of the northern plains of India.
Gondwanaland, is the name given to the more southerly of two supercontinents (the other being Laurasia) that were part of the Pangaea supercontinent that existed from approximately 300 to 180 million years ago (Mya). Gondwana formed prior to Pangaea, then became part of Pangaea, and finally broke up after the breakup of Pangaea. Gondwana is believed to have sutured between about 570 and 510 Mya, thus joining East Gondwana to West Gondwana. It separated from Laurasia 200-180 Mya (the mid-Mesozoic era) during the breakup of Pangaea, drifting farther south after the split.
The land of India displays great physical variation. Geologically, the Peninsular Plateau constitutes one of the ancient landmasses on the earth’s surface. It was supposed to be one of the most stable land blocks. The Himalayas and the Northern Plains are the most recent landforms. From the view point of geology, Himalayan mountains form an unstable zone. The whole mountain system of Himalaya represents a very youthful topography with high peaks, deep valleys and fast flowing rivers. The northern plains are formed of alluvial deposits. The peninsular plateau is composed
of igneous and metamorphic rocks with gently rising hills and wide valleys.

INDIA – SIZE AND LOCATION

India is one of the ancient civilisations in the world. It has achieved multi-faceted socioeconomic
progress during the last five decades. It has moved forward displaying remarkable progress in the field of agriculture, industry, technology and overall economic development. India has also contributed significantly to the making of world history.
LOCATION:
India is a vast country. Lying entirely in the Northern hemisphere (Figure 1.1) the main land extends between latitudes 8°4'N and 37°6'N and longitudes 68°7'E and 97°25'E.

The Tropic of Cancer (23° 30'N) divides the country into almost two equal parts. To the southeast and southwest of the mainland, lie the Andaman and Nicobar islands and the Lakshadweep islands in Bay of Bengal and Arabian Sea respectively.
The southernmost point of the Indian Union– ‘Indira Point’ got submerged under the sea water in 2004 during the Tsunami.
SIZE:

The land mass of India has an area of 3.28 million square km. India’s total area accounts for about 2.4% of the total geographical area of the world.India is the seventh largest country of the world. India has a land boundary of about 15,200 km and the total length of the coast line of the mainland including Andaman and Nicobar and Lakshadweep is 7,516.6 km. India is bounded by the young fold mountains in the northwest, north and north east. South of about 22° north latitude, it begins to taper, and extends towards the Indian Ocean, dividing it into two seas, the Arabian Sea on the west and the Bay of Bengal on its east.
From Gujarat to Arunachal Pradesh there is a time lag of two hours. Hence, time along the Standard Meridian of India (82°30'E) passing through Mirzapur (in Uttar Pradesh) is taken as the standard time for the whole country. The latitudinal extent influences the duration of the day and night, as one moves from south to north.




INDIA AND THE WORLD:
The Indian landmass has a central location between the East and the West Asia. India is a southward extension of the Asian Continent. The trans Indian Ocean routes which connect the countries of Europe in the West and the countries of East Asia provide a strategic central location to India. Note that the Deccan Peninsula protrudes into the Indian Ocean, thus helping India to establish close contact with West Asia, Africa and Europe from the western coast and with Southeast and East Asia from the eastern coast. No other country has a long coastline on the Indian Ocean as India has and indeed, it is India’s eminent position in the Indian Ocean which justifies the naming of an Ocean after it.Since the opening of the Suez Canal in 1869, India’s distance from Europe has been reduced by 7,000 km.

India’s contacts with the World have continued through the ages but her relationships through the land routes are much older than
her maritime contacts. The various passes across the mountains in the north have provided passages to the ancient travellers, while the oceans restricted such interaction for a long time. These routes have contributed in the exchange of ideas and commodities since
ancient times. The ideas of the Upanishads and the Ramayana, the stories of Panchtantra, the Indian numerals and the decimal system thus could reach many parts of the world. The spices, muslin and other merchandise were taken from India to different countries. On the other hand, the influence of Greek sculpture, and the architectural styles of dome and minarets from West Asia can be seen in different parts of our country.
INDIA’S NEIGHBOURS:

Before 1947, there were two types of states in India – the provinces and the Princely states. Provinces were ruled directly by British officials who were appointed by the Viceroy. Princely states were ruled by local, hereditary rulers, who acknowledged sovereignity in return for local autonomy.India occupies an important strategic position in South Asia. India has 29 states and 7 Union

Territories. India shares its land boundaries with Pakistan and Afghanistan in the northwest, China (Tibet), Nepal and Bhutan in the north and Myanmar and Bangladesh in the east. Our southern neighbours across the sea consist of the two island countries, namely Sri Lanka and Maldives. Sri Lanka is separated from India by a narrow channel of sea formed by the Palk Strait and the Gulf of Mannar while Maldives Islands are situated to the south of the Lakshadweep Islands.India has had strong geographical and historical links with her neighbours.

Hindu units of time

Vedic and Puranic texts describe units of Kala measurements, from Paramaṇu (about 17 microseconds) to Maha-Manvantara (311.04 trillion years). According to these texts, the creation and destruction of the universe is a cyclic process, which repeats itself forever. Each cycle starts with the birth and expansion (lifetime) of the universe equaling 311.04 trillion years, followed by its complete annihilation (which also prevails for the same duration). The current Universe was created in Padma kalpa, the last day Kalpa of 50th year of Brahma. This is 10.51 billion years ago. This figure is close to the modern estimated age of the universe in ≈ 13.79 billion years.
Various units of time are used across the Vedas, Puranas, Mahabharata, Suryasidhanta etc. Especially, Nimesha's multiple, it varies to 3, 10, 15, 18, 20, 27, 30, 45, 48, 60. At the lower end, these are pretty consistent. The Complete Hindu metrics of time (Kāla Vyavahāra) can be summarised as below.

Unit		Definition	Equivalence (Approx.)
Truti	त्रुटि		0.031 µs
Renu	रेणु	60 Truti	1.86 µs
Lava	लव	60 Renu	0.11 ms
Līkṣaka	लीक्षक	60 Lava	6.696 ms
Lipta	लिप्ता	60 Leekshaka	0.401 s
Vipala	विपल
Pala	पल	60 Lipta	24.1056 s
Vighaṭi	विघटि
Vinādī	विनाडी
Ghaṭi	घटि	60 Vighaṭi	24 min
Nādī	नाडी
Danda	दण्ड
Muhūrta	मुहूर्त	2 Ghaṭi	48 min
Nakṣatra Ahorātram (Sidereal Day)	नक्षत्र अहोरात्रम्	60 Ghaṭī	24 h
		30 Muhūrta	24 h

Alternate system

Unit	Definition	Equivalence (Approx.)
Truti		35.5 µs
Tatpara	100 Truti	3.55 ms
Nimesha	30 Tatpara	106.7 ms
Kāṣṭhā	30 Nimesha	3.2 s
Kalā	30 Kāṣṭhā	1.6 min
Muhūrta	30 Kalā	48 min
Nakṣatra Ahorātram (Sidereal Day)	30 Muhūrta	24 h

Small units of time used in the Vedas

Unit	Definition	Equivalence (Approx.)
Paramāṇu		26.3 µs
Aṇu	2 Paramāṇu	57.7 µs
Trasareṇu	3 Aṇu	158 µs
Truṭi	3 Trasareṇu	474 µs
Vedha	100 Truṭi	47.4 ms
Lava	3 Vedha	0.14 s
Nimeṣa	3 Lava	0.43 s
Kṣaṇa	3 Nimesha	1.28 s
Kāṣṭhā	5 Kṣaṇa	6.4 s
Laghu	15 Kāṣṭhā	1.6 min
Danda	15 Laghu	24 min
Muhūrta	2 Danda	48 min
Ahorātram (Day)	30 Muhūrta	24 h
Masa (Month)	30 Ahorātram	30 days
Ritu (Season)	2 Masa	2 months
Ayana	3 Rutu	6 months
Samvatsara (Year)	2 Ayana	360 days

Lunar metrics
A Tithi or lunar day is defined as the time it takes for the longitudinal angle between the moon and the Sun to increase by 12°.[1] Tithis begin at varying times of day and vary in duration from approximately 19 to approximately 26 hours.
A Paksa (also Pakṣa) or lunar fortnight consists of 15 tithis.
A Māsa or lunar month (approximately 29.5 days) is divided into 2 Pakṣas: the one between new moon and full moon (waxing) is called gaura or (bright) or Śukla Pakṣa; the one between full moon and new moon (waning) Kṛiṣhṇa (dark) paksha
A Ṛitu (or season) is 2 Māsa[2]
An Ayana is 3 Ṛitus
A year is two Ayanas [1][3]
Tropical metrics
A Yāma = 1/4 of a day (light) or night [ = 7½ Ghatis (घटि) = 3¾ Muhurtas = 3 Horas (होरा) ]
Four Yāmas make half of the day (either day or night)
Eight Yāmas make an Ahorātra (day + night)
An Ahorātra is a tropical day (Note: A day is considered to begin and end at sunrise, not midnight.)

Name		Definition	Equivalence
Yama	याम	¼ th of a day (light) or night	3 hours
Sāvana Ahorātram	सावन अहोरात्रम्	8 Yamas	1 Solar day

Reckoning of time among other entities.
Among the Pitṛs (forefather) in their Dimension (Loka):
1 human fortnight (15 days) = 1 day (light) or night of the Pitṛs.
1 human month (30 days) = 1 day (light) and night of the Pitṛs.
30 days of the Pitṛs = 1 month of the Pitṛs = (30 × 30 = 900 human days).
12 months of the Pitṛs = 1 year of the Pitṛs = (12 months of Pitṛs × 900 human days = 10800 human days).
The lifespan of the Pitṛs is 100 years of the Pitṛs (= 36,000 Pitṛ days = 1,080,000 human days = 3000 human years)
1 day of the Devas = 1 human year
1 month of the Devas = 30 days of the Devas
1 year of the Devas (1 divine year) = 12 months of the Devas
Among the Devas in their Dimension (Loka):
The life span of any Hindu deva spans nearly (or more than) 4.5 million years. Statistically, we can also look it as:
12000 Deva Years = Life Span of Devas = 1 Mahā-Yuga.
The Viṣṇu Purāṇa Time measurement section of the Viṣṇu Purāṇa Book I Chapter III explains the above as follows:
2 Ayanas (6-month periods, see above) = 1 human year or 1 day of the devas
4,000 + 400 + 400 = 4,800 divine years (= 1,728,000 human years) = 1 Satya Yuga
3,000 + 300 + 300 = 3,600 divine years (= 1,296,000 human years) = 1 Tretā Yuga
2,000 + 200 + 200 = 2,400 divine years (= 864,000 human years) = 1 Dvāpara Yuga
1,000 + 100 + 100 = 1,200 divine years (= 432,000 human years) = 1 Kali Yuga
12,000 divine year = 4 Yugas (= 4,320,000 human years) = 1 Mahā-Yuga (also is equaled to 12000 Daiva (divine) Yuga)
[2*12,000 = 24,000 divine year = 12000 revolutions of sun around its dual]

For Brahma in their Dimension (Loka):
1000 Mahā-Yugas = 1 Kalpa = 1 day (day only) of Brahma
(2 Kalpas constitute a day and night of Brahma, 8.64 billion human years)
30 days of Brahma = 1 month of Brahma (259.2 billion human years)
12 months of Brahma = 1 year of Brahma (3.1104 trillion human years)
50 years of Brahma = 1 Parārdha
2 parardhas = 100 years of Brahma = 1 Para = 1 Mahā-Kalpa (the lifespan of Brahma)(311.04 trillion human years)
One day of Brahma is divided into 1000 parts called charaṇas. The charaṇas are divided as follows:

The Four Yugas

4 charaṇas (1,728,000 solar years)	Satya Yuga
3 charaṇas (1,296,000 solar years)	Treta Yuga
2 charaṇas (864,000 solar years)	Dvapara Yuga
1 charaṇas (432,000 solar years)	Kali Yuga

The cycle repeats itself, so altogether there are 1,000 cycles of Mahā-Yuga in one day of Brahma.

• One cycle of the above four Yugas is one Mahā-Yuga (4.32 million solar years)
• as is confirmed by the Gītā Śloka 8.17 (statement) "sahasra-yuga-paryantam ahar yad brahmaṇo viduḥ rātriṁ yuga-sahasrāntāṁ te 'ho-rātra-vido janāḥ", meaning, a day of brahma is of 1000 Mahā-Yuga. Thus a day of Brahma, Kalpa, is of duration: 4.32 billion solar years. Two Kalpas constitute a day and night (Adhi Sandhi) of Brahma.
• A Manvantara consists of 71 Mahā-Yuga (306,720,000 solar years). Each Manvantara is ruled by a Manu.
• After each Manvantara follows one Saṃdhi Kāla of the same duration as a Kṛta Yuga (1,728,000 = 4 Charaṇas). (It is said that during a Saṃdhi Kāla, the entire earth is submerged in water.)
• A Kalpa consists of a period of 4.32 Billion solar years followed by 14 Manvataras and Saṃdhi Kalas.
• A day of Brahma equals

(14 times 71 Mahā-Yuga) + (15 × 4 Charaṇas)

= 994 Mahā-Yuga + (15 * 4800)

= 994 Mahā-Yuga + (72,000 years)[deva years] / 6 = 12,000[deva years] viz. one maha yuga.

= 994 Mahā-Yuga + 6 Mahā-Yuga

= 1,000 Mahā-Yuga

The Surya Siddhanta definition of timescales

The Surya Siddhanta [Chapter 14 Mānādhyāyah (मानाध्यायः)], documents a comprehensive model of nine divisions of time called māna (मान) which span from very small time units (Prāņa [प्राण] - 4 seconds) to very large time scales (Para [पर] - 311.04 Trillion solar years).