The Aqra - Bekhme, Shiranish, Tanjero and Kolosh formations outcrop in the High Folded Zone, Northern Iraq in Erbil and Sulaymaniyah governorates. The formations have been studied at two selected geological sections (Bekhme Gorge and Zarda Bee). In this study, these formations are investigated based on both benthic and planktonic foraminifera. Depending on foraminifer’s investigation, three biozones have been recognized; two biozones are identified in the benthic foraminifera and the third one is identified in the planktonic foraminifera as follow:

1. Siderolites calcitropodes - Orbitoides apiculatus - Omphalocyclus macroporus Assemblage zone.
2. Loftusia morgani range zone.
3. Aba

The Pila Spi Formation (middle – late Eocene) was studied in terms of field character, Petrography and geochemistry from two outcrops (Bakhar and Bani bawy) sections, Northern Iraq. The field studies showing massive, lithified limestone to marly limestone high effected by dolomitization. The petrography studies shows that most of the skeletal grains was destroyed due to digenetic processes specifically the dolomitization, and the vast majority of carbonate rocks are mudstone and few beds of wackestone. The geochemical study reveals low CaO% and high MgO% content due to the intense effect of dolomitization, and the carbonate rocks was classified as impure limestone generally of slightly calcareous dolomite. Ca/Mg and Sr/Ca ratios have b

A total of 23 samples are collected from Injana and Mukdadiya Formations representing: sandstone (14 samples from Injana Formation and 9 samples from Mukdadiya Formation). 19 sandstone samples are thin sectioned for petrographic study (10 thin sections from Injana and 9 thin sections from Mukdadiya) and 23 sandstone samples are selected for heavy minerals study (14 samples from Injana and 9 samples from Mukdadiya). The petrographic investigations revealed that the sandstone of Injana and Mukdadiya Formations are composed primarily of rock fragments (sedimentary, igneous and metamorphic), quartz (monocrystalline and polycrystalline) and feldspars (orthoclase, microcline and plagioclase). The matrix is subordinate and the cement is mostly

The present study deals with the petrographic investigations revealed that the sandstone of Gercus Formation the studied samples of sandstone units composed primarily of rock fragments (sedimentary, igneous and metamorphic), quartz grains (monocrystalline and polycrystalline), and feldspars (orthoclase, microcline and plagioclase). These components are cemented by carbonate and iron oxides. The studied sandstones are classified as litharenites, Sandstone rocks of Gercus Formation  are chemically and mechanically unstable due to the high percentage of rock fragments ,such a grain assemblage infers that the source of the rock fragments is nearby. The petrographic analyses indicate that the studied sandstones are immature mineralogically b

    The early Carboniferous Harur Formation from the Ora outcrop section of northern Iraq consists of black shale, calcareous shale and carbonate. The mineralogical and geochemical investigations (major and trace elements) of the black shale and calcareous shale units have been conducted to evaluate paleoenvironmental conditions including paleoclimate, paleoredox conditions, paleoproductivity, sedimentary rate, and to evaluate their effects on organic matter accumulation. The geochemical proxies such as the Chemical Index of Alteration (CIA), A-CN-K plot, Sr/Cu ratio, and the relation between the ratio of Ga/Rb and Sr/Cu suggest moderate to intense chemical weathering under humid conditions. The Rb/K and Sr/Ba ratios indicate a freshw

This study deals with the petrology of Injana Formation (Upper Miocene) at
Zawita, Amadia and Zakho areas. The sandstone of Injana Formation is of two
typesnamely, litharenite and feldspathiclitharenite. The rock fragments of Injana
Formation are mostly sedimentary and hence the sandstones are classified as
sedarenite and more specifically chertarenite owing to the predominance of chert
rock fragments. The sandstone is mineralogicallysubmature rangingfrom
mechanically and chemically stable tounstable. The petrographic studies reveal
nearness of source area with arid to semi-arid climate. The source rocks are
sedimentary, low- to medium-grade metamorphic and basic volcanic rocks. They are
mostly supplied from th

Basin analysis (geohistory) is carried out on the Cretaceous to Tertiary succession in five wells at Kirkuk and Bai Hassan Oil Fields during the Aptian to the Recent. The Foothill Zone exhibited a complex subsidence and uplift history over a period of about 132 Ma. The results from studied wells backstripping provide a record of the subsidence and uplift history in a number of important Meso-Cenozoic depositional successions. They show that there are three distinct episodes separated by unconformity surfaces. The value of compaction varies from large during the Cretaceous period to less clearly during the Paleogene and then almost non-existent during the Neogene. Generally, the subsidence is continuous and gradual during Mesozoic and sud