Extraction of petroleum

The extraction of petroleum is the process by which usable petroleum is extracted and removed from the earth.

Locating the oil field

Geologists use seismic surveys to search for geological structures that may form oil reservoirs. The "classic" method includes making an underground explosion nearby and observing the seismic response that provides information about the geological structures under the ground . However, "passive" methods that extract information from naturally-occurring seismic waves are also known.

Other instruments such as gravimeters and magnetometers are also sometimes used in the search for petroleum. Extracting crude oil normally starts with drilling wells into the underground reservoir. When an oil well has been tapped, a geologist (known on the rig as the "mudlogger") will note its presence. Such a "mudlogger" is known to be sitting on the rig. Historically, in the USA, some oil fields existed where the oil rose naturally to the surface, but most of these fields have long since been used up, except in certain places in Alaska. Often many wells (called multilateral wells) are drilled into the same reservoir, to ensure that the extraction rate will be economically viable. Also, some wells (secondary wells) may be used to pump water, steam, acids or various gas mixtures into the reservoir to raise or maintain the reservoir pressure, and so maintain an economic extraction rate.

Petroleum industry in Iraq

Iraq was the world’s 12th largest oil producer in 2009, and has the world’s fifth largest proven petroleum reserves after Venezuela, Saudi Arabia, Canada, and Iran. Just a fraction of Iraq’s known fields are in development, and Iraq may be one of the few places left where vast reserves, proven and unknown, have barely been exploited. Iraq’s energy sector is heavily based upon oil, with approximately 94 percent of its energy needs met with petroleum. In addition, crude oil export revenues accounted for over two-thirds of GDP in 2009. Iraq’s oil sector has suffered over the past several decades from sanctions and wars, and its oil infrastructure is in need of modernization and investment. As of June 30, 2010, the United States had allocated $2.05 billion to the Iraqi oil and gas sector to begin this modernization, but ended its direct involvement as of the first quarter of 2008. According to reports by various U.S. government agencies, multilateral institutions and other international organizations, long-term Iraq reconstruction costs could reach $100 billion or higher.

Iraq

Coordinates: 33°N 44°E / 33°N 44°E / 33; 44

Iraq (/ɪˈræk/, ⁱ/ɪˈrɑːk/, or /aɪˈræk/; Arabic: العراق‎ al-‘Irāq, Kurdish: Êraq), officially the Republic of Iraq (Arabic:  جمهورية العراق  Jumhūrīyat al-‘Irāq; Kurdish: كۆماری عێراق‎ Komar-i ‘Êraq), is a country in Western Asia. The country borders Turkey to the north, Iran to the east, Kuwait to the southeast, Saudi Arabia to the south, Jordan to the southwest, and Syria to the west. The southern part of Iraq is within the Arabian Peninsula. The capital, Baghdad, is in the centre of the country and its largest city. The largest ethnic groups in Iraq are Arabs and Kurds. Other ethnic groups include Assyrians, Turkmen, Shabakis, Yazidis, Armenians, Mandeans, Circassians, and Kawliya. Around 95% of the country's 36 million citizens are Shia or Sunni Muslims, with Christianity, Yarsan, Yezidism, and Mandeanism also present.

Iraq has a narrow section of coastline measuring 58 km (36 mi) on the northern Persian Gulf and its territory encompasses the Mesopotamian Alluvial Plain, the northwestern end of the Zagros mountain range, and the eastern part of the Syrian Desert. Two major rivers, the Tigris and Euphrates, run south through the centre of Iraq and flow into the Shatt al-Arab near the Persian Gulf. These rivers provide Iraq with significant amounts of fertile land.

Mandatory Iraq

The Kingdom of Iraq under British Administration or Mandatory Iraq (Arabic: الانتداب البريطاني على العراق‎ al-Intidāb al-Brīṭānī ‘Alá al-‘Irāq) was created in 1921 following the 1920 Iraqi Revolt against the proposed British Mandate of Mesopotamia, and enacted via the 1922 Anglo-Iraqi Treaty.

Faisal ibn Husayn, who had been proclaimed King of Syria by a Syrian National Congress in Damascus in March 1920, was ejected by the French in July of the same year. Faisal was then granted by the British the territory of Iraq, to rule it as a kingdom, with the British Royal Air Force (RAF) retaining certain military control, though de facto; the territory remained under British administration until 1932.

The civil government of postwar Iraq was headed originally by the High Commissioner, Sir Percy Cox, and his deputy, Colonel Arnold Wilson. British reprisals after the murder of a British officer in Najaf failed to restore order. The most striking problem facing the British was the growing anger of the nationalists, who continued to fight against the imposition of British authority. British administration had yet to be established in Iraqi Kurdistan.

Mesopotamia

Mesopotamia (/ˌmɛsəpəˈteɪmiə/, from the Ancient Greek: Μεσοποταμία "[land] between rivers"; from Ancient Armenian՝ Միջագետք(Mijagetq), Arabic: بلاد الرافدين‎ bilād ar-rāfidayn; Persian: میان‌رودان‎‎ miyān rodān; Syriac: ܒܝܬ ܢܗܪܝܢ‎ Beth Nahrain "land of rivers") is a name for the area of the Tigris–Euphrates river system, roughly corresponding to modern-day Iraq, Syria and Kuwait, including regions along the Turkish-Syrian and Iran–Iraq borders.

Widely considered to be the one of the cradles of civilization by the Western world, Bronze Age Mesopotamia included Sumer and the Akkadian, Babylonian, and Assyrian empires, all native to the territory of modern-day Iraq. In the Iron Age, it was controlled by the Neo-Assyrian and Neo-Babylonian Empires.

The indigenous Sumerians and Akkadians (including Assyrians and Babylonians) dominated Mesopotamia from the beginning of written history (c. 3100 BC) to the fall of Babylon in 539 BC, when it was conquered by the Achaemenid Empire. It fell to Alexander the Great in 332 BC, and after his death, it became part of the Greek Seleucid Empire.