Tectonic Plates of the Earth

A geographical map that shows the extensions of the various plate boundaries of the earth crust and the location of volcanoes at its edges. Move around the map to see the plate boundaries (shown as lines) and the location of volcanoes (show as points) across the globe.


Data Source: Plate Tectonics KML from RSOE EDIS, Volcano of the World KML from www.gelessons.com/kmzfiles/gvp_layer.kmz

Tectonic Plates of the Earth

I am a geologist by education and the topics related to earth science fascinates me a lot. Plate Tectonics is one such topic. Plate Tectonics is a scientific theory dealing with the dynamics of earth’s outer shell, the lithosphere, that revolutionized earth sciences by providing a uniform context for understanding mountain-building processes, volcanoes, and earthquakes, as well as understanding the evolution of earth’s surface and reconstructing its past continental and oceanic configurations. Here I have tried to illustrate plate tectonic through a map.

The earth's crust or the outer shell can be compared to the peel of an orange. Plate tectonics explains that this orange peel-like earth's outer shell is divided into several plates-like structures that glide over the mantle, the inner semi-viscous to solid layer of the above the core. Of course this plate-gliding movement is very slow, like 5 to 10 cm/yr, but in decades of years this speed does make impact. The lines where the plates meet are called plate boundaries. Because of the gliding movements of the plates, tremendous pressures are generated and energy is accumulated at the plate boundaries. And when these energy releases all of a sudden, earthquakes occur.

There are three main types of plate boundary: divergent, convergent and transform. At divergent boundaries, plates move away from one another leading to formation of deep oceanic trenches. At convergent boundaries, plates move towards each other leading to collusion and formation of pile of upraises, like folded mountains. At transform boundaries, plates slide pass one another leading to formation of shear zones accumulating massive frictional forces, which when released causes earthquakes. These activities also create ruptures in the earth crust, through which hot lava, volcanic ash, and gases to escape from a magma chamber below the surface, which are called volcanoes. The image below illustrates the various plate tectonic activities of the earth.

Plate Tectonics model of the Earth Crust

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India Map during the British Rule

A historical map that shows the face of India during the British Rule. Click and check the two types of territories - red and yellow areas. The red areas in the map represents the regions that were directly under the British rule, called the British India territories. The yellow areas represents the Princely States which were ruled by local Indian rulers.

This is the place where history meets technology. The above map shows the face of pre-independent India. The map in pale red and yellow, superimposed on Google Map, shows the geographic extent of the then British Raj in India in the year 1909, showing British India in pale red and the princely states in yellow. The original source (paper format) of this map is Imperial Gazetteer Atlas of India, Plate 20. I some time back digitised these boundaries, converted into the KML format, and then overlaid it on the Google Map frame, to give the original paper format a interactive look and feel.

The British Rule

The British Rule was the period from 1858 to 1947 when rulers from the Great Britain ruled the Indian subcontinent. The region under British control - commonly called India - included areas directly administered by Britain as well as the princely states ruled by individual rulers under the paramountcy of the British Crown. The region is now less commonly also called British Raj or the Indian Empire. The British Raj extended over almost all present-day India, Pakistan, and Bangladesh, with exceptions such as Goa and Pondicherry. In addition, at various times, it also included Lower and Upper Burma, and briefly British Somaliland, and Singapore. Burma was separated from India and directly administered by the British Crown from 1937 until its independence in 1948. The Trucial States of the Persian Gulf were theoretically princely states as well as Presidencies and provinces of British India until 1946.

Among other countries in the region, Ceylon (now Sri Lanka) was ceded to Britain in 1802. Ceylon was part of Madras Presidency between 1793 and 1798. The kingdoms of Nepal and Bhutan, having fought wars with the British, subsequently signed treaties with them and were recognised by the British as independent states. The Kingdom of Sikkim was established as a princely state after the Anglo-Sikkimese Treaty of 1861; however, the issue of sovereignty was left undefined. The Maldive Islands were a British protectorate from 1887 to 1965 but not part of British India.

India during the British Raj was made up of two types of territory: British India and the Native States (or Princely States). A Princely State, also called a Native State or an Indian State, was a nominally sovereign entity with an indigenous Indian ruler, subject to a subsidiary alliance. There were 565 princely states when India and Pakistan became independent from Britain in August 1947. The princely states did not form a part of British India (i.e. the presidencies and provinces), as they were not directly under the British rule. Areas which were directly under the British rule are known as British India.

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Commuting in Mumbai

An informative map that shows the rapid transit commuter railway network system of Mumbai. Mumbai Suburban Railway and Mumbai Metro together forms the rapid transit commuter railway network system in the Mumbai Metropolitan Region. Click to expand the legend button on top-left corner of the map window and check the content details. Zoom-in or out and play around the map to check the locations.


Map last updated in May 2023

Mumbai Suburban Railway Network

Mumbai Suburban Railway forms the suburban railway network and is also called the Mumbai lifeline. Spread over 465 kilometres (289 miles), the suburban railway operates 2,342 train services and carries more than 7.5 million commuters daily. By annual ridership of 2.64 billion commuters, the Mumbai Suburban Railway is the busiest rapid transit system in the world.

The Mumbai Suburban Railway system is operated by Indian Railways' two zonal divisions Western Railways (WR) and Central Railways (CR) with two corridors in each – The Fast line and the Slow line. The fast commuter rail corridors on Central Railway as well as Western Railway are shared with long distance and freight trains. WR operates the Western Line and CR operates the Central Line, Harbour Line, Trans-Harbour Line as well as the Vasai Road-Diva-Panvel line.

The Western Line follows the Western Railway northwards from Churchgate parallel to the west coast. Local services by electric multiple units (EMUs) ply between Churchgate and Dahanu Road (120 km) on exclusive parallel tracks up to Virar (60 km) while Mainline Electrical Multiple Units (MEMUs) service the section beyond Virar to Dahanu Road (60 km)

The Central Line in Mumbai consists of 3 major corridors, which bifurcate as they run into suburban satellite towns. The two corridors follow the Central Railway run from Chhatrapati Shivaji Terminus (CST) to Kalyan (54 km), from where it bifurcates into two lines – one to Kasara (67 km) in the north-east and the other to Khopoli (61 km) in the south-east. These two corridors constitute the 'main' Central Line. There is also an 18-km corridor between Kurla and Thane stations for use of outstation and cargo trains. The corridor is being extended further from Thane to Kalyan now as a part of the main line. The Central Line has two interchange stations with the Western Line at Parel and Dadar.

The Harbour Line is part of the Central Railway, and runs from Chhatrapati Shivaji Terminus (CST) to Andheri and Panvel. All Harbour Line services operate as slow services. The line operates from two separate platforms at Chhatrapati Shivaji Terminus (CST), and the tracks cross over the main line at Sandhurst Road, to head towards stations along Mumbai's eastern dock area. A branch line from Wadala Road joins the Western Line at Mahim and continues towards Andheri. The Harbour Line has an interchange station with the main line at Kurla, where it turns east towards Navi Mumbai. The Harbour Line further bifurcates at Vashi into two lines – one rejoins the main lines at Thane, while the other continues to Panvel.

The Trans-Harbour Line connects Navi Mumbai to Thane. It runs from Thane to Vashi, Nerul and Panvel.

Mumbai Metro Network

Mumbai Metro is a Mass Rapid Transit System (MRTS) to provide fast, easy and comfortable commute through high-speed trains in Mumbai. The system is designed to reduce traffic congestion in the city, and supplement the overcrowded Mumbai Suburban Railway network. The system comprise of total eleven high-capacity lines, out of which three are fully operational as of now (May 2023), eight are under construction, and six are proposed, spanning a total of 338.5 kilometres (210.3 miles).

With so many metro lines and their extensions under construction or proposed, the Mumbai Metropolitan Region Development Authority (MMRDA) is making all efforts in expanding the metro network within and around the Mumbai city. The Mumbai Metro network comprises the following lines:

Fully Operational Metro Lines:
Line 1: Versova - Andheri - Ghatkopar metro corridor, called the Blue Line, having 12 stations, covering 11.40 km
Line 2A: Dahisar(E) - Andheri West metro corridor, called the Yellow Line, having 17 stations, covering 18.60 km
Line 7: Dahisar (East) - Gundavali metro corridor, called the Red Line, having 13 stations, covering 16.50 km

Under Construction Metro Lines:
Line 2B: Andheri West - Mandala metro corridor, called the Yellow Line, having 22 stations, covering 23.60 km
Line 3: Colaba - Bandra - SEEPZ metro corridor, called the Aqua Line, having 27 stations, covering 33.50 km
Line 4: Wadala - Mulund - Thane - Kasarvadavali metro corridor, called the Green Line, having 32 stations, covering 32.32 km
Line 4A: Kasarwadavali - Gaimukh metro corridor, extension of the Green Line, having 2 stations, covering 2.88 km
Line 5: Thane - Bhiwandi - Kalyan metro corridor, called the Orange Line, having 17 stations, covering 24.90 km
Line 6: Swami Samarth Nagar - KanjurMarg - Vikhroli metro corridor, called the Pink Line, having 13 stations, covering 14.70 km
Line 7A: Andheri (E) - CSI Airport metro corridor, called the Red Line, having 2 stations, covering 3.17 km
Line 9: Dahisar (E) - Mira Bhayander metro corridor, called the Red Line, having 8 stations, covering 11.38 km

Proposed Metro Lines:
Line-8: CSIA - NMIA metro corridor, named the Gold Line, having 7 stations, covering 35.00 km
Line-10: Gaimukh - Shivaji Chowk (Mira Road) metro corridor, named the Green Line, having 9 stations, covering 9.20 km (Approved)
Line-11: Wadala - Chhattrapati Shivaji Maharaj Terminus metro corridor, named the Green Line, having 11 stations, covering 12.70 km (Approved)
Line-12: Kalyan - Dombivali - Taloja metro corridor, named the Orange Line, having 17 stations, covering 20.70 km (Approved)
Line-13: Shivaji Chowk (Mira Bhayander) - Virar metro corridor, named the Purple Line, having 20 stations, covering 23.00 km
Line-14: Kanjurmarg - Badlapur metro corridor, named the Magenta Line, having 40 stations, covering 45.00 km

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Mountain Ranges of the World

A simple yet useful map that summaries and illustrates the approximate geographical extents of various mountain ranges across the surface of the earth with location of their associated major peaks. Click to expand the legend button on top-left corner of the map window and check the content details. Zoom-in or out and play around the map to check the locations. Also, click on the red triangles on the map representing the summits to see their height details from mean sea level.



Let’s go back to the school days geography class and ask this questions - where are the mountain ranges and peaks located on this earth? Well, now no need to search them one by one in the map. The above map shows all mountain peaks and ranges in one place.

Mountains are elevated land masses with peaks smaller than their base. A mountain range is a geographic area containing numerous highlands or mountain passes and valleys. Geologically explained, mountains are formed from collision of continent and upward convergence of the crust at continent edges. Mountains are of 4 types, classified based on the mode of their origin or formation: 1) Folded Mountains, 2) Block Mountains, 3) Volcanic Mountains, and 4) Relict or Residual Mountains.

Folded Mountains are formed by the crumbling or tag of crust rocks resulting in huge wrinkles and folds. These are result of earthquakes. Himalayas, Alps, Andes, etc. are the examples of folded mountains. Block Mountains formed by the lifting up of rock blocks between faults or by the sinking of the crust outside the faults. Volcanic Mountains are formed from accumulation of volcanic material that has erupted from inside the earth in the form of lava. Mount Fujiyama in Japan and Mount Visuvlus in Italy are examples of Volcanic Mountains. Relict or Residual Mountains are those which are deeply dissected and reduced by weathering and river action. All these mountain formation process are slow but gradual and takes millions and millions of years.

Now some facts about mountains. We all know that Mount Everest is the highest mountain on earth with its peak at 8,848 metres (29,029 ft) above sea level. However, that’s not exactly true. Some of the world’s tallest mountains lie mostly underwater. Mauna Kea in Hawaii rises 33,480 ft (10,205 m) from the ocean bed, which makes it taller than Mount Everest. The longest mountain chain on land is the Andes, which runs for 4,470 miles (7,200 km) down the western edge of South America. An undersea mountain chain called the Mid-Atlantic Ridge is even longer. It stretches 7,000 miles (11,300 km) down the center of the Atlantic Ocean. All major tectonic activities on earth are associated with mountain ranges in some way or other.

Nevertheless, mountainous regions are mostly tourist attractions. Mountains are generally calm and splendor places on the earth that helps us to relax. Mountains also offer us sites for outdoor activities like hiking, trekking, skiing, snowboarding, etc. People like tourists, adventure lovers (hikers, trekkers, etc.), or even general enthusiast may need to browse through the above maps to find locations of mountainous regions and summits on the earth.

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