Pub Date : 2020-12-30DOI: 10.33899/earth.2020.170371
S. Al-hamed, K. Aswad, Nabaz R. H. Aziz
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 AlbianCenomenian. 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 (An32.53An33.62). 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 Shareef T. Al-Hamed et al., 65 studied pegmatites appear to entail further dissection mainly due to the fact that the occurrence of dioriticand gabbroic-pegmatites with a small-scale in the single intrusion might have its explanation in the liquid associated immiscibility.
伟晶岩岩脉及其伴生深成岩是与伊拉克东北部扎格罗斯缝合带(ZSZ)的Bulfat杂岩伴生火成岩杂岩的一部分。布尔法特杂岩是含蛇绿岩地体的一部分，是异质片。该复合体代表了阿尔巴尼亚-亚美尼亚的上异域生物。研究区位于ZSZ Bulfat复合体内，特别是在该复合体的西北部和penjwen - walash分区的第二单元内。岩样采自位于达里什玛纳村东北方向的伟晶岩岩脉，岩脉厚度约5 m。8个闪长质伟晶岩点斜长石的电子探针分析(EMPA)范围介于低长岩(an18.00 ~ an28.23)和安长岩(an32.53 ~ an33.62)之间。对14个样品进行了整体化学分析，结果表明，伟晶岩的碱度指数(AI)为铝质(A/NK > 2)，硅含量在46.70 ~ 52.67 wt. %之间。稀土元素相对平坦，低稀土元素比高稀土元素略微富集，表明所研究的伟晶岩具有共同的祖先。这些伟晶岩在LILEs (Sr, Pb, Rb)中富集，而在hfse (Nb, Ta, Y)中富集，表明了岛弧的环境特征。此外，(Rb/Sr)N和(Ba/Sr)N的比值较低，说明这些伟晶岩为基性起源。构造判别图表明，研究的伟晶岩的构造环境为i型，为亚碱性岩石的大洋岛弧环境。研究区伟晶岩与其附近的侵入岩有成因关系;这些侵入物为Wadi Rashid辉长岩，代表了E-MORB的环境。此外，Wadi Rashid的辉长岩和所研究的伟晶岩是蛇绿岩地体的一部分，它们被发现于上异体逆冲片内。目前伟晶岩的研究反映了海洋岛弧环境，表明双岛弧的存在，第一个岛弧靠近阿拉伯陆架，第二个岛弧靠近古脊中部。地球化学、构造作用、伟晶岩与辉长岩在空间上的紧密分布等证据表明，瓦地拉希德辉长岩可能是伟晶岩的母岩。此外，Shareef T. al - hamed等65所研究的伟晶岩似乎需要进一步的解剖，主要是因为在单一侵入岩中出现的小尺度闪长岩和辉长岩伟晶岩可能与液体相关的不混溶有关。
{"title":"Geochemistry and Petrogenesis of Dioritic-Gabbroic Pegmatites in the Bulfat Complex, Qala Diza, Northeastern Iraq","authors":"S. Al-hamed, K. Aswad, Nabaz R. H. Aziz","doi":"10.33899/earth.2020.170371","DOIUrl":"https://doi.org/10.33899/earth.2020.170371","url":null,"abstract":"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 AlbianCenomenian. 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 (An32.53An33.62). 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 Shareef T. Al-Hamed et al., 65 studied pegmatites appear to entail further dissection mainly due to the fact that the occurrence of dioriticand gabbroic-pegmatites with a small-scale in the single intrusion might have its explanation in the liquid associated immiscibility.","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114842066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.33899/earth.2020.170372
F. Al-Miamary, A. Al-Jubory, S. Al-Lhaebi
The study deals with succession from the upper part of the Late Albian Balambo Formation which are composed of fine-grained dark gray to black calcareous shale, limestone and marly limestone rich in sedimentary structures such as lamination, fissility and platy structures. Microfacies analysis revealed that mudstone, wackstone and few of يرامعملا دبع حلاف نورخآو 87 packstone are the main facies in the studied succession. The studied rocks generally are rich in organic matter and pyrite in addition to dominance of radiolaria, sponge spicules and foraminifera with elongated champers maybe “Schackoina” genus. All these characters indicate deposition in marine conditions with reduced or absent-oxygen condition that relate to oceanic anoxic event (1d).
{"title":"Sedimentological and Biological indicators of oceanic anoxic events (1d) inside upper Balambo Formation, L. Albian, northeastern Iraq","authors":"F. Al-Miamary, A. Al-Jubory, S. Al-Lhaebi","doi":"10.33899/earth.2020.170372","DOIUrl":"https://doi.org/10.33899/earth.2020.170372","url":null,"abstract":"The study deals with succession from the upper part of the Late Albian Balambo Formation which are composed of fine-grained dark gray to black calcareous shale, limestone and marly limestone rich in sedimentary structures such as lamination, fissility and platy structures. Microfacies analysis revealed that mudstone, wackstone and few of يرامعملا دبع حلاف نورخآو 87 packstone are the main facies in the studied succession. The studied rocks generally are rich in organic matter and pyrite in addition to dominance of radiolaria, sponge spicules and foraminifera with elongated champers maybe “Schackoina” genus. All these characters indicate deposition in marine conditions with reduced or absent-oxygen condition that relate to oceanic anoxic event (1d).","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121487628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.33899/earth.2020.170358
Narjis Al-Ali, S. Al-Khafaji
Limestone deposits of Ibrahim Formation in Zurbatiya area, eastern Iraq are assessed as raw materials for the industry of Ordinary Portland Cement (OPC). The deposits are widely exposed in the area close to Iraq-Iran borders. Six samples were collected from selected section of Ibrahim Formation, which consists of a succession of well-bedded white to gray limestone interbedded with gray marl and marly limestone. X-ray diffraction results show that calcite is the dominant mineral followed by quartz and traces of dolomite which appear in limited samples. X-ray fluorescence results revealed a noticeable increase of SiO2, which might be due to the effect of limestone by silicification process, so the rocks are considered to be a siliceous limestone. The other oxides (CaO, Al2O3, Fe2O3, MgO, Na2O, K2O, TiO2, SO3, and P2O5) are within the acceptable limits required for cement industry. Cement chemical parameters indicated that there is a decrease in the lime saturation factor (LSF) and an increase in silica ratio (SR) in comparison with the chemical parameters listed by standard specifications due to the increase of silica content. This increase can be adjusted by adding clays, or any other source of low silica content in addition to use iron and alumina as correcting additive materials for the cement mixture.
{"title":"Assessment of Limestone of Ibrahim Formation in Zurbatiya Area, Eastern Iraq for Ordinary Portland Cement Industry","authors":"Narjis Al-Ali, S. Al-Khafaji","doi":"10.33899/earth.2020.170358","DOIUrl":"https://doi.org/10.33899/earth.2020.170358","url":null,"abstract":"Limestone deposits of Ibrahim Formation in Zurbatiya area, eastern Iraq are assessed as raw materials for the industry of Ordinary Portland Cement (OPC). The deposits are widely exposed in the area close to Iraq-Iran borders. Six samples were collected from selected section of Ibrahim Formation, which consists of a succession of well-bedded white to gray limestone interbedded with gray marl and marly limestone. X-ray diffraction results show that calcite is the dominant mineral followed by quartz and traces of dolomite which appear in limited samples. X-ray fluorescence results revealed a noticeable increase of SiO2, which might be due to the effect of limestone by silicification process, so the rocks are considered to be a siliceous limestone. The other oxides (CaO, Al2O3, Fe2O3, MgO, Na2O, K2O, TiO2, SO3, and P2O5) are within the acceptable limits required for cement industry. Cement chemical parameters indicated that there is a decrease in the lime saturation factor (LSF) and an increase in silica ratio (SR) in comparison with the chemical parameters listed by standard specifications due to the increase of silica content. This increase can be adjusted by adding clays, or any other source of low silica content in addition to use iron and alumina as correcting additive materials for the cement mixture.","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122848472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.33899/earth.2020.170374
Mahmood A. H. Al-Sumaidaie, N. Al-Azzawi, Rabeea Znad
In the current study, a tectonic model for the structure of Aqra Anticline was proposed. The model was dependent on the rock properties, stratigraphic relationships and thickness variations as well as, the model was correlated with other previous يعديمصُلا قحلا دبع دومحم نورخآو 127 studies. The study area is located within the Iraqi Zagros fold/ thrust belt (ZFTB) which represents the northeastern margin of the Arabian Plate. Stratigraphically, the anticline comprises of formations that are deposited between Early Cretaceous to Pliocene periods. These formations are the Sarmord, Qamchuqa, Aqra, Kolosh/Khurmala, Gercus, Pila Spi, Fat'ha, Injana, and the Makdadiya formations. they were deposited during four Tectonostratigraphic Megasequences (TMS). The older TMS contains formations that were deposited prior the development of the Zagros Foreland Basin, whereas the formations of other three Megasequences were deposited within Zagros Foreland Basin. During those times, the foreland basin was divided into three distinct parts. these are fore deep, bulge, and fore-bulge, which were discriminated via listric faults, which played as normal and reverse displacements after and before ophiolite obduction. Some contributions to the tectonostratigraphic model of the area are adopted. They are stages of basin development, determining the time of extension period of the listric faults and detecting the tectonic inversion of these faults. This model is described within the compressional tectonic framework between the Arabian and Eurasian plates.
{"title":"Effect of Tectonostratigraphic Units in Evolving Aqra Anticline Model","authors":"Mahmood A. H. Al-Sumaidaie, N. Al-Azzawi, Rabeea Znad","doi":"10.33899/earth.2020.170374","DOIUrl":"https://doi.org/10.33899/earth.2020.170374","url":null,"abstract":"In the current study, a tectonic model for the structure of Aqra Anticline was proposed. The model was dependent on the rock properties, stratigraphic relationships and thickness variations as well as, the model was correlated with other previous يعديمصُلا قحلا دبع دومحم نورخآو 127 studies. The study area is located within the Iraqi Zagros fold/ thrust belt (ZFTB) which represents the northeastern margin of the Arabian Plate. Stratigraphically, the anticline comprises of formations that are deposited between Early Cretaceous to Pliocene periods. These formations are the Sarmord, Qamchuqa, Aqra, Kolosh/Khurmala, Gercus, Pila Spi, Fat'ha, Injana, and the Makdadiya formations. they were deposited during four Tectonostratigraphic Megasequences (TMS). The older TMS contains formations that were deposited prior the development of the Zagros Foreland Basin, whereas the formations of other three Megasequences were deposited within Zagros Foreland Basin. During those times, the foreland basin was divided into three distinct parts. these are fore deep, bulge, and fore-bulge, which were discriminated via listric faults, which played as normal and reverse displacements after and before ophiolite obduction. Some contributions to the tectonostratigraphic model of the area are adopted. They are stages of basin development, determining the time of extension period of the listric faults and detecting the tectonic inversion of these faults. This model is described within the compressional tectonic framework between the Arabian and Eurasian plates.","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133440311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.33899/earth.2020.170353
Mahmood Al-Fadhel, Marwan Mutib
The field survey included three geoelectric traverses on the eastern side of the Tigris River parallel and perpendicular on the axis of the Tairah anticline consisting of seven sites of ( Azimuthal Resistivity Tomography; ART) located above the Quaternary depositions in the southern flank. Two traverses were also conducted in the western side of the river parallel and perpendicular on the east Butmah anticline consisting of four sites located above the recent sediments in the southern flank of it. The sites are chosen taking into account the consideration of the geological, tectonic and topographic data of previous studies and current field reconnaissance trips. A sympathetic analysis of the resistivity tomography is performed in nine azimuths of the above mentioned locations using fifteen repetitive processing attempts and the mean root squares ranged between 5.8% -11.7%. The eastern side of the study area with different directions indicates electrical horizons, the first reflects a variable resistivity which represents accumulations of top soil, the second band of high resistivity which reflects the river terraces constitutes, while the third horizon represents the clear extension of the mud and limestone deposits of Fatha Formation with a vertical conductive zones in the rock layers at some traverses. As well as the ART on the western side of the study region identified three electric horizons: the first with high resistivity reflecting the surface soil layer, and the second domain of low resistivity representing the sediments of the valley slopes and concentrating on the southern limb of Butmah anticline. The third of heterogeneous resistivity values reflects Fatha Formation deposits covering its exposures at the core of the two anticlines and locating beneath the research traverses. Using the technology of 2D resistivity imaging reveals that the nine orientations around a central point in eleven locations above recent sediments are represented by river terraces and alluvial deposits on the shoulders of the Mosul Dam. The current study concludes the ability to capture fractures, which is of great importance due to their effect on the displacements of the dam's body and Fatha sediments surrounding it.
{"title":"Study of the Quaternary Deposits at the East and West Shoulders of Mosul Dam Using Azimuthal 2D Resistivity Imaging","authors":"Mahmood Al-Fadhel, Marwan Mutib","doi":"10.33899/earth.2020.170353","DOIUrl":"https://doi.org/10.33899/earth.2020.170353","url":null,"abstract":"The field survey included three geoelectric traverses on the eastern side of the Tigris River parallel and perpendicular on the axis of the Tairah anticline consisting of seven sites of ( Azimuthal Resistivity Tomography; ART) located above the Quaternary depositions in the southern flank. Two traverses were also conducted in the western side of the river parallel and perpendicular on the east Butmah anticline consisting of four sites located above the recent sediments in the southern flank of it. The sites are chosen taking into account the consideration of the geological, tectonic and topographic data of previous studies and current field reconnaissance trips. A sympathetic analysis of the resistivity tomography is performed in nine azimuths of the above mentioned locations using fifteen repetitive processing attempts and the mean root squares ranged between 5.8% -11.7%. The eastern side of the study area with different directions indicates electrical horizons, the first reflects a variable resistivity which represents accumulations of top soil, the second band of high resistivity which reflects the river terraces constitutes, while the third horizon represents the clear extension of the mud and limestone deposits of Fatha Formation with a vertical conductive zones in the rock layers at some traverses. As well as the ART on the western side of the study region identified three electric horizons: the first with high resistivity reflecting the surface soil layer, and the second domain of low resistivity representing the sediments of the valley slopes and concentrating on the southern limb of Butmah anticline. The third of heterogeneous resistivity values reflects Fatha Formation deposits covering its exposures at the core of the two anticlines and locating beneath the research traverses. Using the technology of 2D resistivity imaging reveals that the nine orientations around a central point in eleven locations above recent sediments are represented by river terraces and alluvial deposits on the shoulders of the Mosul Dam. The current study concludes the ability to capture fractures, which is of great importance due to their effect on the displacements of the dam's body and Fatha sediments surrounding it.","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116132202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.33899/earth.2020.170370
Zainab M. Shanshal, Ahmed Al-Heety
It is important to determine the location, depth and shape (dimensions) of cavities under subsurface in site investigation phase before construction. This study aims to make a study for properties, analysis and comparison of the results of different electrodes configurations that used in 2-D electrical resistivity Tomography surveys to detection subsurface cavities to determining the appropriate and suitable configurations type that must be conduct in the field to obtain best and accurate results. Two-dimensional synthetic models were created for Geoelectrical resistivity of five different geological features, which reflects the common cases of cavities in nature. These models are (narrow, broad, shallow and deep) cavities adding to one model for multiple cavities. RES2DMOD program was used to create these models, while RES2DINV program used in Inversion method to obtain the true 2-D inverted resistivity sections for six configuration types of electrode array for 2D electrical resistivity technique, after adding a Gaussian noise ratio of (5%). Generally, we are noticed the possibilities of most tested configuration types for determine electrical anomalies, because the high contrast between the cavities and the surrounding rocks resistivities values. In addition, RMS ratio overall does not exceed 5%, hence, this ratio is an acceptable and indicates to the quality of the inverse process. The Wenner array have high sensitivity to vertical resistivity variations, and Dipole-dipole array have high sensitivity to lateral resistivity variations. While the Schlumberger-wenner have high sensitivity in both lateral and vertical resistivity variations Also, it was noted that the efficiency of all types decreasing with increasing depth of cavities detecting, due to the low percentage of contrast between the cavities and the surrounding rocks. The Wenner beta (WB) configuration is the best choice in terms of inversing true resistivity values, Secondly the Pole-Dipole (PD). While in term of determining the location and shape (approximately dimensions) of cavities, Dipole-Dipole (DD), Wenner-Schlumberger (WS), Wenner Alpha (WA), Dipole-Pole (DP) respectively. However, in case of noisy areas, Wenner Alpha (WA) configuration gives the best result.
{"title":"Analyzing sensitivity and resolution of some electrical resistivity configurations for detecting subsurface cavities using inverted synthetic models by 2D electrical resistivity tomography technique","authors":"Zainab M. Shanshal, Ahmed Al-Heety","doi":"10.33899/earth.2020.170370","DOIUrl":"https://doi.org/10.33899/earth.2020.170370","url":null,"abstract":"It is important to determine the location, depth and shape (dimensions) of cavities under subsurface in site investigation phase before construction. This study aims to make a study for properties, analysis and comparison of the results of different electrodes configurations that used in 2-D electrical resistivity Tomography surveys to detection subsurface cavities to determining the appropriate and suitable configurations type that must be conduct in the field to obtain best and accurate results. Two-dimensional synthetic models were created for Geoelectrical resistivity of five different geological features, which reflects the common cases of cavities in nature. These models are (narrow, broad, shallow and deep) cavities adding to one model for multiple cavities. RES2DMOD program was used to create these models, while RES2DINV program used in Inversion method to obtain the true 2-D inverted resistivity sections for six configuration types of electrode array for 2D electrical resistivity technique, after adding a Gaussian noise ratio of (5%). Generally, we are noticed the possibilities of most tested configuration types for determine electrical anomalies, because the high contrast between the cavities and the surrounding rocks resistivities values. In addition, RMS ratio overall does not exceed 5%, hence, this ratio is an acceptable and indicates to the quality of the inverse process. The Wenner array have high sensitivity to vertical resistivity variations, and Dipole-dipole array have high sensitivity to lateral resistivity variations. While the Schlumberger-wenner have high sensitivity in both lateral and vertical resistivity variations Also, it was noted that the efficiency of all types decreasing with increasing depth of cavities detecting, due to the low percentage of contrast between the cavities and the surrounding rocks. The Wenner beta (WB) configuration is the best choice in terms of inversing true resistivity values, Secondly the Pole-Dipole (PD). While in term of determining the location and shape (approximately dimensions) of cavities, Dipole-Dipole (DD), Wenner-Schlumberger (WS), Wenner Alpha (WA), Dipole-Pole (DP) respectively. However, in case of noisy areas, Wenner Alpha (WA) configuration gives the best result.","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127805958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-10DOI: 10.33899/earth.2020.170373
S. Al-Lhaebi, A. Al-Jubory, F. Al-Miamary
In the current work, the Gulneri Formation (Early Turonian) is studied in three surface sections (Degala, Dokan and Azmir) from northeastern Iraq. The formation is characterized by grey to black color limestone and marly limestone in the Degala and يحتف ناوفص يبيهللا نورخآو 106 Dokan sections, whereas in Azmir section, fissile marl and marly limestone with pale to reddish color are dominated in addition to few beds, which occasionally contain fish remains, with distinct gray color reflecting the very few amount of total organic carbon in these beds. Microfacies analysis revealed that the formation consists of three microfacies: mudstone, wackestone and packstone. The predominance of dwarfish planktonic foraminifera (Heterohilex) and thin shell filaments particularly in packstone microfacies represent Heterohelix shift event and filament event respectively. In addition to these events, fish remains, radiolarian pyritization, planktonic foraminiferal chambers elongation and glauconite are all refer to anoxic environmental conditions that may have been coincided with the Global Cenomanian-Turonian Oceanic Anoxic Event (OAE-2).
{"title":"Sedimentological, Paleontological and Mineralogical Evidences for Oceanic Anoxic Event-2 (OAE-2) in the Gulneri Formation (Early Turonian), Northeastern Iraq","authors":"S. Al-Lhaebi, A. Al-Jubory, F. Al-Miamary","doi":"10.33899/earth.2020.170373","DOIUrl":"https://doi.org/10.33899/earth.2020.170373","url":null,"abstract":"In the current work, the Gulneri Formation (Early Turonian) is studied in three surface sections (Degala, Dokan and Azmir) from northeastern Iraq. The formation is characterized by grey to black color limestone and marly limestone in the Degala and يحتف ناوفص يبيهللا نورخآو 106 Dokan sections, whereas in Azmir section, fissile marl and marly limestone with pale to reddish color are dominated in addition to few beds, which occasionally contain fish remains, with distinct gray color reflecting the very few amount of total organic carbon in these beds. Microfacies analysis revealed that the formation consists of three microfacies: mudstone, wackestone and packstone. The predominance of dwarfish planktonic foraminifera (Heterohilex) and thin shell filaments particularly in packstone microfacies represent Heterohelix shift event and filament event respectively. In addition to these events, fish remains, radiolarian pyritization, planktonic foraminiferal chambers elongation and glauconite are all refer to anoxic environmental conditions that may have been coincided with the Global Cenomanian-Turonian Oceanic Anoxic Event (OAE-2).","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127202539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-30DOI: 10.33899/earth.2020.170331
A. Al-Jawadi, T. H. Al-Dabbagh
{"title":"The effects of weathering on limestone used for building the cemetery wall in Tel Kaif-North Iraq","authors":"A. Al-Jawadi, T. H. Al-Dabbagh","doi":"10.33899/earth.2020.170331","DOIUrl":"https://doi.org/10.33899/earth.2020.170331","url":null,"abstract":"","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127859215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-30DOI: 10.33899/earth.2020.170347
Hekmat S. Al-Daghastani, Faaza Jasim
The results of the analysis and interpretation of multi-date satellite images for the period between (1987-2007) in the Nineveh’s province to the presence of local spectral anomalies in some areas, reflect a clear change in the pattern of spectral using reflectivity. Analyses of spectral reflectivity using Analytical Spectral Devise (ASD) field Spectro Radiometer for selected samples of soils that have been taken by field work يناتسغادلا يحبص تمكح و مساج يديمح ةزئاف 76 from some sites in the province. They gave spectral anomaly in their profile patterns, compared with other unaffected sites, which have been useful in determining and locating the pollution sites and its classification. Classification of the above pollution sites has been accomplished depending on the comparison of spectral signature of these samples with the field informations. These classes are shown on Geoenvironmental thematic map prepared at scale of 1:50000. This map includes areas of radioactive contamination and environmental, indusial and other of military activity.
{"title":"Spectral analysis of soil samples in environmental pollution sites in Nineveh province, using remote sensing techniques","authors":"Hekmat S. Al-Daghastani, Faaza Jasim","doi":"10.33899/earth.2020.170347","DOIUrl":"https://doi.org/10.33899/earth.2020.170347","url":null,"abstract":"The results of the analysis and interpretation of multi-date satellite images for the period between (1987-2007) in the Nineveh’s province to the presence of local spectral anomalies in some areas, reflect a clear change in the pattern of spectral using reflectivity. Analyses of spectral reflectivity using Analytical Spectral Devise (ASD) field Spectro Radiometer for selected samples of soils that have been taken by field work يناتسغادلا يحبص تمكح و مساج يديمح ةزئاف 76 from some sites in the province. They gave spectral anomaly in their profile patterns, compared with other unaffected sites, which have been useful in determining and locating the pollution sites and its classification. Classification of the above pollution sites has been accomplished depending on the comparison of spectral signature of these samples with the field informations. These classes are shown on Geoenvironmental thematic map prepared at scale of 1:50000. This map includes areas of radioactive contamination and environmental, indusial and other of military activity.","PeriodicalId":371191,"journal":{"name":"Iraqi National Journal of Earth Sciences","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125865058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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