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Northeastern Iraq, contiguous with Iran and Turkey, is part of the Zagros foldbelt, consisting of two zones ([[:file:M106Ch12Fig03.jpg|Figure 3]]). The High Zagros Nappe zone is a topographically high region characterized by tightly folded rocks and by ophiolite which was obducted onto the Arabian plate in the Late Cretaceous ([[:file:M106Ch12Fig04.jpg|Figure 4]]). Cretaceous and older sedimentary rocks and a suite of igneous and metamorphic rocks crop out in this region ([[:file:M106Ch12Fig05.jpg|Figure 5]]). There are no oil and gas discoveries in the High Zagros Nappe zone, although rocks containing bitumen and organic-rich rocks are exposed.

Northeastern Iraq, contiguous with Iran and Turkey, is part of the Zagros foldbelt, consisting of two zones ([[:file:M106Ch12Fig03.jpg|Figure 3]]). The High Zagros Nappe zone is a topographically high region characterized by tightly folded rocks and by ophiolite which was obducted onto the Arabian plate in the Late Cretaceous ([[:file:M106Ch12Fig04.jpg|Figure 4]]). Cretaceous and older sedimentary rocks and a suite of igneous and metamorphic rocks crop out in this region ([[:file:M106Ch12Fig05.jpg|Figure 5]]). There are no oil and gas discoveries in the High Zagros Nappe zone, although rocks containing bitumen and organic-rich rocks are exposed.

[[file:M106Ch12Fig04.jpg|thumb|300px||{{figure number|4}}Regional geologic cross section, which extends NE across central Iraq, from the Arabian platform of southwestern Iraq, at the border with Saudi Arabia, across the Mesopotamian Foredeep and Zagros foldbelt in eastern Iraq and adjacent Iran, and ending at the Sirjan-Sanandaj zone in Iran.]]

file:M106Ch12Fig04.jpg|{{figure number|4}}Regional geologic cross section, which extends NE across central Iraq, from the Arabian platform of southwestern Iraq, at the border with Saudi Arabia, across the Mesopotamian Foredeep and Zagros foldbelt in eastern Iraq and adjacent Iran, and ending at the Sirjan-Sanandaj zone in Iran.

 

file:M106Ch12Fig05.jpg|{{figure number|5}}Regional geologic cross section which extends NE across western Iraq, from the Arabian platform at the border with Jordan, across the Mesopotamian Foredeep and Zagros foldbelt in northwestern Iraq, and ending in adjacent Turkey.

[[file:M106Ch12Fig05.jpg|thumb|300px|{{figure number|5}}Regional geologic cross section which extends NE across western Iraq, from the Arabian platform at the border with Jordan, across the Mesopotamian Foredeep and Zagros foldbelt in northwestern Iraq, and ending in adjacent Turkey.]]

The main part of the Zagros foldbelt is topographically lower and is characterized by large anticlines trending to the northwest. In the southwestern part of the foldbelt, synclinal areas are covered by Neogene sediments. In the northwestern part of the foldbelt, Paleogene strata are exposed in synclines. The Zagros foldbelt forms a large structural embayment, called the Kirkuk embayment, in the overall Zagros foldbelt. Many oil and gas fields occur within this zone, as shown in [[:file:M106Ch12Fig03.jpg|Figure 3]], including the super-giant Kirkuk field.

The main part of the Zagros foldbelt is topographically lower and is characterized by large anticlines trending to the northwest. In the southwestern part of the foldbelt, synclinal areas are covered by Neogene sediments. In the northwestern part of the foldbelt, Paleogene strata are exposed in synclines. The Zagros foldbelt forms a large structural embayment, called the Kirkuk embayment, in the overall Zagros foldbelt. Many oil and gas fields occur within this zone, as shown in [[:file:M106Ch12Fig03.jpg|Figure 3]], including the super-giant Kirkuk field.

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Table 3 lists the reservoir horizons and seals in fields that have produced oil and gas. The same information is shown for undeveloped fields in Table 4 and for small discoveries and wells with shows in Table 6.

Table 3 lists the reservoir horizons and seals in fields that have produced oil and gas. The same information is shown for undeveloped fields in Table 4 and for small discoveries and wells with shows in Table 6. Table 5 lists information by show number and show structure.

[[file:M106Ch12Table2.jpg|thumb|300px|{{table number|2}}List of oil and gas fields and wells with oil and/or gas shows. Field number refers to locations shown in [[:file:M106Ch12Fig03.jpg|Figure 3]]. Hydrocarbon type: oil, gas, or oil and gas. Structural province refers to regions shown in [[:file:M106Ch12Fig03.jpg|Figure 3]]. Structural style of the trap: basement-involved fold, detached fold-thrust, or salt-supported dome. Trap type: anticline, faulted anticline, faulted dome, or fault trap. Source name and age given only where proven by biomarkers. Source strata type: basinal marine (includes calcareous and marly lithologies) or basinal shale. Volumes of oil and gas in-place, estimated ultimate recoverable (EUR), produced, and remaining ultimate recoverable (RUR) age given in millions of barrels of oil (MMBO) and billions of cubic feet of gas (BCFG). Condensate included in oil volumes. Information mainly from Verma et al.<ref name=Vermaetal_2004 /> and Jassim and Goff.<ref name=Jassimandgoff_2006 /> Additional references as shown. Comments reflect the impression of the author.]]

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|+ {{table number|2}}List of oil and gas fields and wells with oil and/or gas shows. Field number refers to locations shown in [[:file:M106Ch12Fig03.jpg|Figure 3]]. Hydrocarbon type: oil, gas, or oil and gas. Structural province refers to regions shown in [[:file:M106Ch12Fig03.jpg|Figure 3]]. Structural style of the trap: basement-involved fold, detached fold-thrust, or salt-supported dome. Trap type: anticline, faulted anticline, faulted dome, or fault trap. Source name and age given only where proven by biomarkers. Source strata type: basinal marine (includes calcareous and marly lithologies) or basinal shale. Volumes of oil and gas in-place, estimated ultimate recoverable (EUR), produced, and remaining ultimate recoverable (RUR) age given in millions of barrels of oil (MMBO) and billions of cubic feet of gas (BCFG). Condensate included in oil volumes. Information mainly from Verma et al.<ref name=Vermaetal_2004 /> and Jassim and Goff.<ref name=Jassimandgoff_2006 /> Additional references as shown. Comments reflect the impression of the author.

There are 107 oil discoveries and nine gas discoveries in Iraq. The majority of these are in the Zagros foldbelt (53), the Mesopotamian foredeep (22), and the Gotnia Basin (18), and they account for over 98% of the oil and gas discovered.

There are 107 oil discoveries and nine gas discoveries in Iraq. The majority of these are in the Zagros foldbelt (53), the Mesopotamian foredeep (22), and the Gotnia Basin (18), and they account for over 98% of the oil and gas discovered.