The Great Himalayas!!

Himalaya is a word made from a combination of Sanskrit words "Hima" and "Alya", which means abode of snow.  Such a fitting name because most of these mountains are covered in snow and contain ten out of fourteen 8000-meter peaks in the world. This mountain range separates the Indian subcontinent and the Tibetan plateau. It is often known as the roof of the world, and rightfully so because it houses 110 peaks rising over and above the height of 7300 meters above sea level.  These mountains carry a very high cultural significance for the people of South Asia, as is visible from their omnipresence across the scriptures, rituals, and folklore of these cultures. In modern times, these mountains have attracted mountaineers from all across the world because of the unique climbing challenges that these mountains provide.

Geographical Spread of Himalayas?

The Himalayan mountain range is approximately 2500 meters long, and its breadth varies between 200-400km across the entire length.  It is spread across five countries starting from Nanga Parbat (8126 m), Pakistan in the west, going through India, Nepal, and Bhutan, and ending in China at the Namchabarwa peak (7756 m). It covers an approximate area of 595,000 square km across these five countries. 

Western Border- Hindu Kush and Karakoram 

Northern Border- Tibetan Plateau

Southern Border- Gangatic Plains of India 

Eastern Border- Brahmaputra Valley 

Key Groupings of Himalayan Mountain Range

The Himalayas can primarily be grouped into four major mountain ranges longitudinally. Starting from the south, they are the Outer/Sub Himalayas (Shiwalik), Lesser or Lower Himalayas (Himachal), Greater Himalayas (Himadri), and Trans Himalayas in Tibet (Tethys). From west to east, the Himalayas are categorized into three groups, namely Western, Central, and Eastern Himalayas. Purvanchal hills that span across the seven sister states of India are also a part of Eastern Himalayas 

Key Features of Different Sections

1. The Trans-Himalayas

Location: North of the Great Himalayas, primarily in Tibet.

Characteristics: This region has high plateaus, deep valleys, and arid conditions. It is a zone of internal drainage with several salt lakes. Granitic rocks and metamorphic formations dominate the landscape. The average elevation is around 4,500 meters.

Significance: The Trans-Himalayas act as a buffer zone between the Tibetan Plateau and the Himalayas, influencing the region's climate and ecology.

2. The Great Himalayas (Himadri)

Location: The core of the Himalayan range.

Characteristics: This is the highest and most rugged part of the Himalayas, featuring the world's tallest peaks like Mount Everest. The region is characterized by steep slopes, glaciers, and perennial snow. The rocks are primarily granitic and metamorphic.

Significance: The Great Himalayas are the water towers of Asia, feeding major river systems like the Ganges, Indus, and Brahmaputra.

3. The Lesser Himalayas (Himachal)

Location: Between the Great Himalayas and the Siwaliks.

Characteristics: This zone is characterized by moderate heights, rounded peaks, and deep valleys. It is often called the 'hill country' known for its temperate climate and forests. The rocks are predominantly sedimentary, with some metamorphic formations.

Significance: The Lesser Himalayas are essential for agriculture and tourism. They also act as a buffer zone between the higher Himalayas and the plains.

4. The Siwaliks (Outer Himalayas)

Location: The southernmost range of the Himalayas.

Characteristics: This is the lowest and most recent part of the Himalayas, composed primarily of unconsolidated sediments. Low hills, river terraces, and alluvial fans characterize it.

Significance: The Siwaliks are essential for agriculture and forestry. They also form a transitional zone between the mountains and the plains. These hills, along with Himachal, house some of the oldest cultures worldwide. 

Formation of Himalayas 

Over millions of years, the Indian Plate, once an independent landmass and part of the erstwhile Gondwana supercontinent, embarked on a northward journey. As it relentlessly moved towards the Eurasian plate, both plates collided around 50 million years ago, and the immense pressure caused the Earth's crust to buckle, fold, and uplift. This process, known as orogeny, gave birth to the Himalayas. This collision resulted in the draining of the Tethys Ocean, which then became the Plateau of Tibet.

The collision was so forceful that the Indian plate is still moving northward, albeit at a slower pace. This ongoing tectonic activity is evident in the frequent earthquakes that occur in the region. The Himalayas are, in essence, a young and dynamic mountain range, continuously evolving as the two continental plates continue to exert pressure on each other.

The formation of the Himalayas is a complex geological process involving many factors. While the initial collision was the primary driver, subsequent uplift, erosion, and glaciation have shaped the range into its current form.

River Systems (Drainage) of the Himalayas 

The Himalayas, with their towering peaks and extensive glaciers, feed a complex network of rivers that have shaped the history, culture, and economy of the region. The Himalayan drainage is composed of three major river systems, namely, the Indus, Ganges, and Brahmaputra River systems. 

The Indus River System

Originating in the Tibetan Plateau, the Indus River is the westernmost of the three major Himalayan rivers. It flows through the Ladakh region of India before entering Pakistan, where it forms a vast alluvial plain. Its tributaries, including the Jhelum, Chenab, Ravi, Beas, and Sutlej, join it to create a substantial river system. The Indus is crucial for irrigation, hydropower generation, and sustaining life in the arid regions of Pakistan.   

The Ganges River System

The Ganges, revered as a holy river by Hindus, originates in the Gangotri Glacier in the Himalayas. It flows through India and Bangladesh, eventually emptying into the Bay of Bengal. The Brahmaputra, another mighty river, joins the Ganges to form the world's largest delta. The Ganga-Brahmaputra river system is the lifeline of North India and Bangladesh, providing water for agriculture, industry, and domestic use.   

The Brahmaputra River System

Originating in the Tibetan Plateau as the Yarlung Tsangpo, the Brahmaputra enters India in Arunachal Pradesh as the Dihang River. It joins the Ganges in Bangladesh, forming the Sundarbans Delta. Known for its immense water volume and swift currents, the Brahmaputra is vital for irrigation, hydropower, and inland water transport.   

Characteristics of Himalayan Rivers

Glacial Origin: Most Himalayan rivers are fed by glaciers, resulting in perennial flow.   

Steep Gradient: The rivers in their upper reaches have a steep gradient, leading to rapid flow and erosion.   

Alluvial Plains: As they descend from the mountains, these rivers form vast alluvial plains, known for their fertility.

Deltas: The major rivers form large deltas at their mouths, supporting rich biodiversity and agriculture.

Hydropower Potential: The steep gradient and high water flow make the Himalayan rivers a significant source of hydropower.

Soil of Himalayas

Shiwalik (Outer Himalayas)

The Shiwalik range, also known as the Outer Himalayas, lies at the foothills of the Himalayas, with elevations ranging from 600 to 1,200 meters. The region experiences a subtropical climate with heavy monsoon rains, leading to the formation of fertile alluvial soils in river valleys. These soils are sandy and loamy, making them ideal for agriculture. In the lower Terai region, the soil is more clayey and waterlogged, supporting dense vegetation and rice cultivation. However, the area is prone to soil erosion due to deforestation and heavy rainfall, often resulting in less fertile, coarse-grained soils.

Lower Himalayas (Himachal)

The Lower Himalayas, or the Lesser Himalayas, range between 1,200 and 4,500 meters in elevation. This region enjoys a temperate climate, supporting a variety of flora and fauna. The prevalent soil type here is brown forest soil, rich in organic matter due to decomposing leaf litter. These soils are moderately acidic and well-drained, supporting dense forests of oak, pine, and rhododendron. At higher altitudes, podzolic soils, which are acidic and nutrient-poor, are found. They support coniferous forests but are less suitable for agriculture.

Greater Himalayas (Himadri)

The Greater Himalayas, also known as the High Himalayas, are the highest range, with peaks soaring above 4,500 meters. This region is characterized by a cold, harsh climate, with snow-covered peaks and glaciers. The soils here are predominantly alpine, thin, and poorly developed, with a high proportion of rock fragments. Organic content is low due to limited vegetation and slow decomposition rates. In the highest regions, permafrost and gelisols are common, remaining frozen most of the year and supporting minimal vegetation.

Trans Himalayas (Tethys)

The Trans Himalayas, located north of the Greater Himalayas, include regions like Ladakh and Tibet. This range is characterized by a cold, arid climate with sparse precipitation and vegetation. The soils here are predominantly desert soils, sandy and gravelly with high salinity and low organic matter. These soils support sparse alpine vegetation and are generally infertile. In valleys and along rivers, alluvial soils can be found, which are more fertile and suitable for limited agriculture, mainly supported by irrigation.

Source: Wikipedia, Britannica and ScienceDirect