Oil reserve is an essential yardstick for measuring a country's economic prosperity.
And proven oil reserves are those that claim to have a reasonable certainty (normally at least 90 per cent confidence) of being recoverable under existing economic and political conditions.
present here a list of countries with highest proven oil reserves.
India ranks 20th in the list.
1. Venezuela
Proven reserve: 296,500,000,000 billion barrels
According to the United States Geological Survey (a bureau of the United States Department of the Interior that employs approximately 8,670 people), the Orinoco Belt alone is estimated to contain 900-1,400 billion barrels (2.2 1011 m3) of heavy crude in proven and unproven deposits.
The crude oil that Venezuela has is very heavy by international standards, and as a result much of it must be processed by specialised domestic and international refineries. Venezuela continues to be one of the largest suppliers of oil to the United States, sending about 1.4 million barrels per day.
2. Saudi Arabia
Proven reserve: 264,600,000,000 billion barrels
Proven reserve: 264,600,000,000 billion barrels
The Saudi reserves are about one-fifth of the world's total conventional oil reserves.
Although Saudi Arabia has around 100 major oil and gas fields, over half of its oil reserves are contained in only eight giant oil fields, including the Ghawar Field, the biggest oil field in the world.
The Saudi reserves are about one-fifth of the world's total conventional oil reserves.
3. Canada
Proven reserve: 175,200,000,000 billion barrels
Canada has a highly sophisticated energy industry and is both an importer and exporter of oil and refined products.
Proven reserve: 175,200,000,000 billion barrels
Canada has a highly sophisticated energy industry and is both an importer and exporter of oil and refined products.
Over 99 per cent of Canadian oil exports are sent to the United States, and Canada is the United States' largest supplier of oil.
4. Iran
Proven reserve: 150,600,000,000 billion barrels
Iranian production peaked at 6 million barrels per day in 1974.
Proven reserve: 150,600,000,000 billion barrels
Iranian production peaked at 6 million barrels per day in 1974.
However, the country has been unable to produce at that rate since the 1979 Iranian Revolution because of a combination of political unrest, war with Iraq, limited investment, US sanctions etc.
High oil prices in recent years have enabled Iran to amass nearly $60 billion in foreign exchange reserves.
5. Iraq
Proven reserve: 143,500,000,000 billion barrels
Proven reserve: 143,500,000,000 billion barrels
After more than a decade of sanctions and two Gulf Wars, Iraq's oil infrastructure needs modernisation and investment.
It should also be mentioned that because of military occupation and civil unrest, the official statistics have not been revised since 2001 and are largely based on 2-D seismic data from three decades ago.
International geologists and consultants have estimated that unexplored territory may contain vastly larger reserves.
6. Mexico
Proven reserve: 139,020,000,000 billion barrels
Proven reserve: 139,020,000,000 billion barrels
The constitution of Mexico gives the state oil company, Pemex, exclusive rights over oil production.
The Mexican government treats Pemex as a major source of revenue.
As a result, Pemex has insufficient capital to develop new and more expensive resources on its own.
7. Kuwait
Proven reserve: 104,000,000,000 billion barrels
Proven reserve: 104,000,000,000 billion barrels
Oil reserves in Kuwait make up 8 per cent of the oil reserves in the world.
Most of Kuwait's oil reserves are located in the 70 billion barrels Burgan field, which has been producing oil since 1938.
Most of Kuwait's major oil fields are over 60 years old and, therefore, maintaining production rates is becoming a problem.
8. United Arab Emirates
Proven reserve: 97,800,000,000 billion barrels
Proven reserve: 97,800,000,000 billion barrels
Most of the oil is in the Zakum field which is the third largest in West Asia with an estimated 66 billion barrels.
The UAE's reserves-to-production is about 93 years.
9. Russia
Proven reserve: 74,200,000,000 billion barrels
Proven reserve: 74,200,000,000 billion barrels
A turnaround in Russian oil output began in 1999, which many analysts attribute to the privatisation of the industry.
It is the largest producer and exporter of oil in the world, other than the Arab League.
10. Libya
Proven reserve: 47,000,000,000 billion barrels
Proven reserve: 47,000,000,000 billion barrels
Libya is considered a highly attractive oil area due to its low cost of oil production (as low as $1 per barrel at some fields), and proximity to European markets.
About 85 per cent of Libyan oil is exported to European markets.