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As igneous rocks have widely chemical and mineralogical compositions, there are many ways to classify these rocks. These ways are classical approved methods to give a reliable classification and nomenclature of rocks. Some igneous rocks may be classified by digital image processing to assist in classical methods. Five igneous samples were cut, prepared of thin sections, and polished to classify them by classical methods and digital image processing by ENVI software. Moreover, part of these samples crushed an analysis of major oxides. The current igneous samples have referred to the basic and mesocratic rocks based on the classical methods and this has corresponded to ENVI software. The igneous samples have reflected the leucogabbros when classify them by classical and ENVI classifications, except the G5 sample, which has been referred to as gabbro by ENVI. There is a clear similarity between the classical and ENVI classifications. ENVI classification is a reliable classification to assist the classical methods in the nomenclature of igneous rocks, especially, plutonic rocks, it can be also applied to thin sections of volcanic rocks to classify and nomenclature classification by ENVI has been applied on fifty thin sections of limestones to identify microfacies which are classified beforehand by classical (optical) classification. According to optical classification, microfacies have classified as mudstone, wackestone, packstone, and grainstone. When the digital classification is applied to them, there is no grainstone texture found in these them. Digital thin sections, where the true name of these microfacies is packstone. Therefore, the positive sides of the digital image processing by ENVI software appeared and contrasted to the optical classification which contained some mistakes when applied to the nomenclature of these microfacies.

The Tanjero Formation is exposed on the Northern flank of the Perat anticline near the Northern entrance to the Bakhme gorge through which the waters of the Upper Zab flow. As for tectonics, it is located within the High Folded Zone of the Unstable Shelf. The Tanjero Formation is about 80 m. thick, it is bounded from the bottom by the Shiranish Formation. The formation consists of gray sandstone that contains gravel at the bottom followed by beds of marl, hard sandstone, and black claystone containing cushioning structures and small-scale cross-bedding are present. According to the Williams classification, theTanjero sandstones drop at the lithic wacke field. The provenance of these sandstones was investigated based on their minerals and geochemical composition. The geochemical analyses showed low silica, a negative correlation of silica with the most major oxides due to recycling sedimentary sources or weathering of silicates. The index of compositional variability indicates that the sandstones of the Tanjero Formation are immature clastic sediments and the high index of compositional variability values confirm that the clastic sediments occurred in the tectonically-active-settings area. Moderate chemical weathering has dominated in the studied area, which was inferred from the chemical index of alteration, the chemical index of weathering and the plagioclase index of alteration. Based on the tectonic discrimination diagrams, the Tanjero sandstones are quartzose sedimentary provenance, felsic igneous rocks source, transitional arc–lithic recycled setting, and located in the collision zone between the passive Arab margin and the effective Iranian-Turkish margin that formed the orogeny belt along the collision zone.

The pegmatite dikes and associated plutonic rocks stand as a part of the igneous complexes associated with the Bulfat complex, located in the Zagros Suture Zone (ZSZ), NE Iraq. The Bulfat complex is a part of the ophiolite-bearing terranes that are allochthonous sheets. The complex represents the upper allochthon of the Albian-Cenomenian. The study area is located within Bulfat complex of ZSZ, specifically in the northwestern part of this zone and within the second unit of the Penjween-Walash Subzone. The rock samples were collected from pegmatite dike which is located to the northeast of the Darishmana village, the thickness of dike is about 5 m.Electron microprobe analyses (EMPA) of plagioclase in 8 spots of dioritic pegmatites ranges between oligoclase (An18.00-An28.23) and andesine (An32.53-An33.62). Bulk whole-rock chemical analysis of fourteen samples using ICP-MS analysis reveals alkalinity Index (AI) of pegmatites to be metaluminous (A/NK > 2). Generally, the silica content in these pegmatites is from 46.70 wt. % to 52.67 wt. %.The relatively flat pattern of REEs is characterized by the slight enrichment of LREEs compared to HREEs indicating the common ancestry of the studied pegmatites. Also, the enrichment of these pegmatites in LILEs (Sr, Pb, Rb) and depletion in HFSEs especially (Nb, Ta, Y) indicate the environment of the island arcs. Moreover, the low ratios of (Rb/Sr)N and (Ba/Sr)N refer to that these pegmatites are derived from a basic origin.Tectonic discriminate diagrams show that the tectonic environment of studied pegmatites is I-type, which is the oceanic island arcs environment of sub alkaline rocks. The pegmatites of the present study have a genesis relationship with intrusions close to them in the study area; these intrusions are gabbros of Wadi Rashid that represent the environment of E-MORB. Moreover, the gabbros of Wadi Rashid and studied pegmatites are part of ophiolite-bearing terranes, they are found within upper allochthon thrust sheet. The current study of pegmatites reflects the oceanic island arcs environment, this indicates the existence of double island arcs, the first adjacent to the Arabian shelf, and the second close to the middle of paleo-ridge.Numerous evidences support that the gabbros of Wadi Rashid being as the likely parent to the studied pegmatites such as geochemistry, tectonogenesis, and the close spatial distribution of the pegmatites to the gabbros of Wadi Rashid. Moreover, the

Pegmatite intrusions represent one of the distinguished geological features which are exposed in the north western part of Zagros Suture Zone-ZSZ whose forms appear like dikes and its contain of Volcano-Sedimentary units. In order to determine these features in some areas northern Iraq, remote sensing techniques were used by applying selective image processing methods for determining the spectral signature of these intrusions. Lithological samples were collected and analyzed geochemically and specify Mode analysis of minerals phases and consequently determination the suitable samples for spectral extraction. Depending on the extracted spectral, digital classification was applied on the corrected satellite images to extract the compatible spectral signatures between pegmatite intrusions (in satellite images) and pegmatite field samples. The results showed coincident between this two pegmatite and also determine another zones of pegmatite out of studied area. The density of pegmatite is more in the zone which is located northwestern part from samples area and low density in the other area. The research method gave good efficiency in pegmatite investigation by clarifying these features on the satellite images.