2,803
edits
Changes
Jump to navigation
Jump to search
Line 38:
Line 38: − [[file:M106Ch12Fig02.jpg|thumb|300px|{{figure number|2}}Bouguer gravity (right) and total magnetic field (left) maps of Iraq, from Jassim and Goff,<ref name=Jassimandgoff_2006>Jassim, S. Z. and Goff, J. C., 2006, Geology of Iraq: Dolin, Prague, and Moravian Museum, Brno, 341 p.</ref> compiled by GEOSURV. The gravity map shows low values in the Zagros foldbelt and Mesopotamian foredeep due to the thick sedimentary section. Orientations of features trend to the north and northwest in southern, western, and northwestern Iraq, interpreted in part to be caused by the structural grain of Precambrian accreted terrains. 200 km (124.3 mi).]]+ + + + − − [[file:M106Ch12Fig03.jpg|thumb|300px|{{figure number|3}}Map of tectonic provinces of Iraq, showing major structural features. Fields and significant wells with oil and/or gas shows are shown; numbers refer to Tables 1–5. Red lines are approximate locations of stratigraphic charts in [[:file:M106Ch12Fig04.jpg|Figure 4]] and [[:file:M106Ch12Fig05.jpg|Figure 5]].]] − [[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: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.]]+ + Line 656:
Line 658: − + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
no edit summary
One effect of the surface relief of Iraq is the flow of groundwater deeply within the sediments of the Mesopotamian foredeep, from the somewhat higher Arabian platform in western and southern Iraq, as well as within synclines in the Kirkuk embayment of the Zagros foldbelt. Freshwater extends far into the subsurface because of these flows.
One effect of the surface relief of Iraq is the flow of groundwater deeply within the sediments of the Mesopotamian foredeep, from the somewhat higher Arabian platform in western and southern Iraq, as well as within synclines in the Kirkuk embayment of the Zagros foldbelt. Freshwater extends far into the subsurface because of these flows.
<gallery mode=packed heights=200px widths=200px>
M106Ch12Fig02.jpg|{{figure number|2}}Bouguer gravity (right) and total magnetic field (left) maps of Iraq, from Jassim and Goff,<ref name=Jassimandgoff_2006>Jassim, S. Z. and Goff, J. C., 2006, Geology of Iraq: Dolin, Prague, and Moravian Museum, Brno, 341 p.</ref> compiled by GEOSURV. The gravity map shows low values in the Zagros foldbelt and Mesopotamian foredeep due to the thick sedimentary section. Orientations of features trend to the north and northwest in southern, western, and northwestern Iraq, interpreted in part to be caused by the structural grain of Precambrian accreted terrains. 200 km (124.3 mi).
M106Ch12Fig03.jpg|{{figure number|3}}Map of tectonic provinces of Iraq, showing major structural features. Fields and significant wells with oil and/or gas shows are shown; numbers refer to Tables 1–5. Red lines are approximate locations of stratigraphic charts in [[:file:M106Ch12Fig04.jpg|Figure 4]] and [[:file:M106Ch12Fig05.jpg|Figure 5]].
</gallery>
==Tectonic setting==
==Tectonic setting==
Iraq is located in the northern part of the Arabian tectonic plate. The basement rocks are presumed to be accretionary rocks assembled during the Late Precambrian Pan-African orogeny, although no wells reach the basement rock in Iraq. Bouguer gravity values are low in the northeast, presumably due to the extreme thickness of sedimentary rocks ([[:file:M106Ch12Fig02.jpg|Figure 2]]), and become progressively higher to the west onto the Khleisia High (Rutbah subzone of Jassim and Goff<ref name=Jassimandgoff_2006 />) along the Iraq–Syria border. North- and northwest-trending basement grains are interpreted from gravity and magnetic data in southern, western, and northwestern Iraq as shown in [[:file:M106Ch12Fig02.jpg|Figure 2]].
Iraq is located in the northern part of the Arabian tectonic plate. The basement rocks are presumed to be accretionary rocks assembled during the Late Precambrian Pan-African orogeny, although no wells reach the basement rock in Iraq. Bouguer gravity values are low in the northeast, presumably due to the extreme thickness of sedimentary rocks ([[:file:M106Ch12Fig02.jpg|Figure 2]]), and become progressively higher to the west onto the Khleisia High (Rutbah subzone of Jassim and Goff<ref name=Jassimandgoff_2006 />) along the Iraq–Syria border. North- and northwest-trending basement grains are interpreted from gravity and magnetic data in southern, western, and northwestern Iraq as shown in [[:file:M106Ch12Fig02.jpg|Figure 2]].
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.
<gallery mode=packed heights=200px widths=200px>
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.
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.
</gallery>
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.
| 41 || 93 || Diwan || Hartha/Sadi || Late Cretaceous || Carbonate || Upper Hartha || Argillaceous limestone ||
| 41 || 93 || Diwan || Hartha/Sadi || Late Cretaceous || Carbonate || Upper Hartha || Argillaceous limestone ||
|-
|-
|
| 47 || 93 || Diwan || Nahr Umr || Early Cretaceous || Sandstone || Upper Nahr Umr || Shale ||
|-
| 50 || 93 || Diwan || Ratawi/Yamama || Early Cretaceous || Carbonate || Ratawi || Shale ||
|-
| 58 || 93 || Diwan || Najmah/Sargelu || Late-Middle Jurassic || Carbonate || Gotnia || Evaporite ||
|-
| 42 || 88 || Dujaila || Sadi || Late Cretaceous || Carbonate || Sadi || Marl ||
|-
| 44 || 88 || Dujaila || Mishrif || Late Cretaceous || Carbonate || Khasib || Argillaceous limestone ||
|-
| 44 || 90 || Gharraf || Mishrif || Late Cretaceous || Carbonate || Khasib || Argillaceous limestone ||
|-
| 49 || 90 || Gharraf || Zubair || Early Cretaceous || Sandstone || Upper Shale Member || Shale ||
|-
| 51 || 90 || Gharraf || Yamama || Early Cretaceous || Carbonate || Ratawi || Shale ||
|-
| 8 || 54 || Gilabat || Injana || Miocene || Sandstone || Injana || Shale ||
|-
| 10 || 54 || Gilabat || Fatha || Miocene || Carbonate || Fatha || Evaporite-Marl ||
|-
| 12 || 54 || Gilabat || Jeribe/Euphrates || Miocene-Oligocene || Carbonate || Fatha || Evaporite-Marl ||
|-
| 40 || 8 || Gusair || Shiranish || Late Cretaceous || Carbonate || Aaliji || Shale ||
|-
| 46 || 8 || Gusair || Mauddud || Early Cretaceous || Carbonate || Mushorah || Evaporite ||
|-
| 12 || 83 || Halfaya || Jeribe/Euphrates/Kirkuk || Miocene-Oligocene || Carbonate || Fatha || Evaporite ||
|-
| 42 || 83 || Halfaya || Sadi/Tanuma || Late Cretaceous || Carbonate || Hartha || Argillaceous limestone ||
|-
| 44 || 83 || Halfaya || Khasib || Late Cretaceous || Carbonate || Tanuma || Shale ||
|-
| 44 || 83 || Halfaya || Mishrif || Late Cretaceous || Carbonate || Khasib || Argillaceous limestone ||
|-
| 47 || 83 || Halfaya || Nahr Umr || Early Cretaceous || Sandstone || Upper Nahr Umr || Shale ||
|-
| 51 || 83 || Halfaya || Yamama || Early Cretaceous || Carbonate || Ratawi || Shale ||
|-
| 13 || 44 || Hamrin || Jeribe/Euphrates || Miocene-Oligocene || Carbonate || Fatha || Evaporite ||
|-
| 44 || 44 || Hamrin || Mishrif/Rumaila || Late Cretaceous || Carbonate || Khasib || Argillaceous limestone ||
|-
| || 26 || Hawler (Benenan) || Alan || Early Jurassic || Carbonate || Alan || Evaporite || Press Releases
|-
| 41 || 82 || Huwaiza || Hartha || Late Cretaceous || Carbonate || Upper Hartha || Argillaceous limestone ||
|-
| 42 || 82 || Huwaiza || Sadi || Late Cretaceous || Carbonate || Hartha || Argillaceous limestone ||
|-
| 43 || 82 || Huwaiza || Khasib || Late Cretaceous || Carbonate || Tanuma || Shale ||
|-
| 44 || 82 || Huwaiza || Mishrif || Late Cretaceous || Carbonate || Khasib || Argillaceous limestone ||
|-
| 47 || 82 || Huwaiza || Nahr Umr || Early Cretaceous || Sandstone || Upper Nahr Umr || Shale ||
|-
| 40 || 55 || Injana || Shiranish || Late Cretaceous || Carbonate || Aaliji || Marl ||
|-
| 41 || 55 || Injana || Kometan || Late Cretaceous || Carbonate || Shiranish || Marl ||
|-
| 22 || 33 || Ismail || Kirkuk Group || Oligocene || Carbonate || Fatha || Evaporite ||
|-
| 12 || 57 || Jaria Pika || Jeribe/Dhiban/Euphrates/Serikagni || Miocene-Oligocene || Carbonate || Fatha || Evaporite ||
|-
| 12 || 21 || Jawan || Jeribe/Euphrates || Miocene-Oligocene || Carbonate || Fatha || Evaporite ||
|-
| 41 || 21 || Jawan || Hartha || Late Cretaceous || Carbonate || Shiranish || Marl ||
|-
| 12 || 43 || Judaida || Jeribe || Miocene || Carbonate || Fatha || Evaporite ||
|-
| 14 || 33 || Judaida || Dhiban || Miocene || Carbonate || Dhiban || Evaporite ||
|-
| 20 || 43 || Judaida || Euphrates || Oligocene || Carbonate || Dhiban || Evaporite ||
|-
| 22 || 43 || Judaida || Kirkuk Group || Oligocene || Carbonate || Basal Serikagni || Evaporite ||
|-
| 43 || 43 || Judaida || Kometan || Late Cretaceous || Carbonate || Kometan || Shale ||
|-
| 12 || 38 || Khanuqah || Jeribe/Euphrates/Kirkuk || Miocene || Carbonate || Fatha || Evaporite ||
|-
| 10 || 56 || Khashm Al Ahmar || Fatha || Miocene || Carbonate || Fatha || Evaporite ||
|-
| 12 || 56 || Khashm Al Ahmar || Jeribe/Dhiban/Euphrates/Serikagni || Miocene || Carbonate || Fatha || Evaporite ||
|-
| 47 || 75 || Kifl || Nahr Umr || Early Cretaceous || Sandstone || Upper Nahr Umr || Shale ||
|-
| 49 || 75 || Kifl || Zubair || Early Cretaceous || Sandstone || Upper Shale Member || Shale ||
|-
| 58 || 75 || Kifl || Najmah/Sargelu || Late-Middle Jurassic || Carbonate || Gotnia || Evaporite ||
|-
| 12 || 40 || Kor Mor || Jeribe/Euphrates/Kirkuk || Miocene-Oligocene || Carbonate || Fatha || Evaporite ||
|-
| 44 || 87 || Kumait || Mishrif || Late Cretaceous || Carbonate || Khasib || Argillaceous limestone ||
|-
| 47 || 87 || Kumait || Nahr Umr || Early Cretaceous || Sandstone || Upper Nahr Umr || Shale ||
|-
| || 118 || Kurdamir || Kirkuk Group || Oligocene || Carbonate || Fatha || Evaporite || Press Releases
|-
| || 118 || Kurdamir || Shiranish || Late Cretaceous || Carbonate || Aaliji || Shale || Press Releases
|-
| 9 || 98 || Majnoon || Ghar || Miocene || Sandstone || Fatha || Evaporite-Marl ||
|-
| 8 || 98 || Majnoon || Fatha || Miocene || Carbonate || Fatha || Evaporite-Marl ||
|-
| 40 || 98 || Majnoon || Shiranish || Late Cretaceous || Carbonate || Aaliji || Shale ||
|-
| 41 || 98 || Majnoon || Hartha || Late Cretaceous || Carbonate || Shiranish || Marl ||
|-
| 42 || 98 || Majnoon || Sadi || Late Cretaceous || Carbonate || Hartha || Argillaceous Limestone ||
|-
| 43 || 98 || Majnoon ||
|}
|}