Petroleum Production Sites of the World

An illustrative map showing petroleum production sites and their respective generalized petroleum basins occurring globally. In the map, “Oil Production Site” means the oil drills from where petroleum is recovered from the earth surface. And “Oil Field Basin” means a system of source and reservoir rocks where petroleum was formed, migrated and trapped. Click on the Oil Production Sites (red circles) or the Oil Field Basins (orange polygons) to know details about them.


Map Source and Credits:

1. Oil Production Sites (Point data): Giant Oil and Gas Fields of the World (Compiled by M.K. Horn)
2. Generalised Oil Field Basins (Polygonals): Drawn by Vinod Rowmuria, author of this blog site, taking reference from petroleum geology literatures.

What is this Map about?

Today’s world economy is driven by crude oil and the petroleum industry. Petroleum is the main source of energy till date and it is essential to maintain the present industrial civilization. Many industries run on petroleum products. And therefore its availability is a critical concern for many nations worldwide. The world has seen many wars because of this black gold.

Have you wondered how and where on this earth petroleum is produced? Going back to some basic geology, petroleum is a naturally occurring hydrocarbon material that is believed to have formed from animal and vegetable debris buried in deep sedimentary rock beds for millions of years. The petroleum, being less dense than the surrounding water, was expelled from the source beds and migrated upward through porous rock such as sandstone and some limestone until it was finally blocked by nonporous rock such as shale or dense limestone. In this way, petroleum deposits came to be trapped by geologic features caused by the folding, faulting, and erosion of the Earth’s crust. See the image below to understand the five ways how petroleum reservoirs are formed in the earth crust.

Petroleum is recovered mostly through oil drilling in the earth crust. Although natural petroleum springs or seepages are also found but such occurrences are very rare. Oil drilling comes after the studies of structural geology at the reservoir scale, sedimentary basin analysis, reservoir characterization, mainly in terms of the porosity and permeability of geologic reservoir structures. It is refined and separated, most easily by industrial distillation, into a large number of consumer products, from gasoline (petrol) and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 90 million barrels each day.

USA has come up as a huge contributor to the total petroleum production in the world. Its contribution amounts to almost 25% of the total production of petroleum globally. Subsequent contributors in this line of huge petroleum producing countries are Saudi Arabia, Russia, China, United Arab Emirates, etc. A complete list of countries by its petroleum production can be found here.

Petroleum is a fossil fuels. It take millions of years to form and therefore it is also considered to be a non-renewable energy source. We should use petroleum products (oil and gas) judiciously and try to save them as far as possible. Five ways how Petroleum reservoirs are formed can be understood from the self-explanatory image below. In the above map the Oil Production Sites i.e., those red circles represent the locations on the earth's surface from where the Petroleum reservoirs are accessed through sub-surface drilling to collect the crude oil from the trap shown below.

Subsurface accumulations of Oil and Gas in Reservoir

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Europe Map during Nazi Domination

A illustrative map showing the face of Europe during the height of Nazi domination under Hitler’s rule between 1939 and 1945. This page and the map are intended not to praise the Nazi rule but only to show the geographic extents of the deadly regime in Europe for educational purpose only.




One of the darkest and deadliest phases in the World History is the domination of Hitler’s regime from 1920s to 1945, when it went on capturing most of the European countries, and wiping out less than half of the world Jewish population alone. The Nazi Germany power rose to its peak during World War II, which finally ended after Soviet Union regained its power, a retaliating fight against Nazis of 3-years, suicide of Hitler, and final surrendering of Nazis in front of the Red Army in Berlin. The total number of non-combatants (civilians who are not taking a direct part in war) deliberately killed by the Germans were about 11 million, a figure that rises to more than 12 million if foreseeable deaths from deportation, hunger, and sentences in concentration camps are included.

The Rise and Fall of the Nazi Germany

At the height of its domination, Hitler ruled Nazi Germany occupied most of the European countries at various times between 1939 and 1945. Hitler’s victory-journey started in March 1938 when the Nazis occupied Austria. Later the same year they marched into the Sudetenland, a part of Czechoslovakia, and in March 1939 the German army invaded the rest of Czechoslovakia. This brought over half a million Jews under German control

The German invasion of Western Poland in September 1939 led to the start of the World War-II. The German army continued invading and occupied many other European countries, including the Netherlands, Belgium, Luxembourg, France, Denmark, Yugoslavia, Greece, Norway and Western Poland. By this time many millions of Jews were living in territories under German control.

Control of Nazi occupied territories was very critical. The Nazis often left local governments in place, provided they were either sympathetic or could be easily manipulated (called puppet regimes). Each occupied nation was appointed a Gauleiter – a senior Nazi official who ruled in the manner of a governor. The level of control and force wielded in each occupied country was often based on Hitler’s personal perception of it. Economies in occupied countries were forced to assist the Nazi war effort, with cheap supplies and labour. There were also social restrictions, such as control of the press, obligatory identity cards, checkpoints and curfews.

The most brutal Nazi occupation was in Poland. In September 1939 the Polish state was divided in two, with the invading Germans occupying the western half and the Soviet Union’s Red Army occupying the east. By early 1941 most Polish Jews population had been forced out of their homes and herded into ghettos and slave labour.

By the summer of 1940, the Nazis controlled much of Western Europe, including eastern France, the Baltic States. This occupation would not change significantly until the D-Day landings and the Soviet Union’s counter attack of 1944. Riding on the victory-journey, the Nazis continued moving towards east and invaded Soviet Union. By early December, 1941, the German stood less than 30 km from the Kremlin, (Moscow center) and they were able to see some of Moscow’s buildings with binoculars. But after being mired in a war of attrition deep into the Soviet Union for nearly 3 years, the Nazi offensive was no longer sustainable. Under the leadership of the Soviet leader Stalin, the Red Army planned winter offensive to teach lessons to the Nazi Germans. When the invasion began in the summer of 1941, Hitler took it for granted that victory would be swift, not preparing a contingency plan for a prolonged battle in harsh, Russian winter conditions. By early 1944, the Germans could not sustain their siege on the USSR any longer, and were forced into an all-out retreat. Suffering from a high loss of life and lack of supplies (due to continued attacks on supply lines), the Nazi army was also severely weakened, making it ripe for pursuing Soviet forces

By April 1945 the Soviet forces fought their way into the center of Berlin. Unable to bear the humiliating defeat from the Soviet Red Army, followed by the news of execution of Mussolini, Hitler presumably decided to finish himself to avoid his capture. On 29 April 1945, in a small civil ceremony in the Führerbunker, Hitler married Eva Braun and then on the very next day, he committed suicide by taking cyanide and shooting himself. The Nazi German forces then surrendered in front of the Soviet forces in Berlin on 2 May 1945.

How the map was created

I analysed various historical maps in image formats showing Nazi domination in the internet and downloaded a few with reliable information. I used these as raster images for input in ArcGIS. I then tried to geo-reference these image maps on top of world countries layer in ArcGIS. Although the geo-referencing was not very precise as the countries dataset has a scale of 1:3 million, not matching with that of the image maps, but an approximate geo-referencing was achieved. Once the raster images are geo-referenced on top of the countries shapefile, I tried to draw the historical boundaries showing in the image maps in a trial and error basis. Once the boundaries are drawn, I ran a series of Geoprocessing tasks in ArcGIS to clean and carve out the final maps from downloaded countries dataset. Sometimes the last two steps needed repetition in sequence back and forth to get the desired outcome. The final carved-out maps were in the form of shapefiles, with names and attributions as per the image maps. I then converted these shapefiles into Google’s KML format to overlay on top of Google map as shown in the above map.

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United Kingdom Explained through Map

An informative map that illustrates the difference between England, Britain and the United Kingdom, which appears as the same place in general, but are geographically different places. Click to expand the legend button on top-left corner of the map window and click to check-uncheck the layer names to visualize the differences.

Difference between England, Britain and the United Kingdom

When people refer the terms United Kingdom, England, or Britain, I am sure most of them think these are the same place, unless they know the truth. And the truth is that these are different places. The above map on top of Google map tries to illustrate the differences, highlighting the following areas:

1.  The United Kingdom - The United Kingdom is not a single country but instead is a country of countries. It contains the following 4 sovereign nations:
  1.  England - Often confused as United Kingdom, largest and most populous of the 4 countries, shown in red.
  2.  Scotland – Situated towards north of England, shown in green.
  3.  Wales – Situated towards west of England, shown in orange.
  4.  Northern Ireland - Often forgotten or excluded, shown in light blue.
Although people of United Kingdom are thought as British, but actually people from England are English, people from Scotland are Scottish, Wales are Welsh, and Northern Ireland are Northern Irish. So the full name is the United Kingdom of Great Britain and Northern Ireland.

2.  Great Britain - Great Britain is a geographical term rather than a political term and within the United Kingdom it covers the area formed by England, Scotland, and Wales, excluding Northern Ireland. Great Britain is the biggest island within United Kingdom.
Great Britain is also an island of islands belonging to the individual admins England, Scotland, and Wales. For example, the Isle of Wight, Isles of Scilly and Lundy belongs to England. The Isle of Anglesey belongs to Welsh. Scotland has maximum number of islands grouped under Hebrides, Orkney Islands, Shetland Islands, and Islands of the Clyde. Apart from these islands there are some other islands which come directly under the Crown, controlled by the British monarchy, and are called the Crown Dependencies.

3.  Crown Dependencies –These includes the following islands. These are not considered independent nations, but are granted local autonomy by the Crown and British Citizenship by the United Kingdom.
  1.  The Isle of Man
  2.  Guernsey Islands
  3.  Bailiwick of Jersey

4.  British Islands – The United Kingdom countries, together with the Crown Dependencies form the British Islands. So British Islands includes Great Britain (i.e., England, Scotland, and Wales), Northern Ireland, Isle of Man, Guernsey, and Bailiwick of Jersey. One interesting thing to note here is that the British Islands do not cover the whole Ireland, but only Northern Ireland. Ireland is the biggest island in the British Isles. Like Great Britain, Ireland is not a country; it is a geographical term, not political.

5.  Ireland - The island of Ireland contain on it two countries - Northern Ireland and the Republic of Ireland. One interesting fact is that when people say they are ‘Irish’ they are actually referring to the Republic of Ireland and not Northern Ireland.

6.  British Isles - So the two largest islands in the British Isles are Ireland and Great Britain.

 Apart from the above entities two other types of Crown Dependencies, not shown in the map, are:
  1.  Commonwealth Countries – These are independent nations of the former British Empire that still recognize the Crown. These countries do not rely on the United Kingdom for military and economic assistance.
  2.  British Overseas Territories - Unlike the Commonwealth Realm, these have not become independent nations and continue to rely on the United Kingdom for military and (sometime) economic assistance. Like the Crown Dependencies, everyone born in their borders is a British Citizen.

Source: CGP Grey

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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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