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1.
001-es BibID:
BIBFORM126013
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Remote sensing and gravity investigations for barite detection in Neoproterozoic rocks in the Ariab area, Red Sea Hills, Sudan / Daoud, Abazar M.A.; Shebl, Ali; Abdelkader, Mohamed M.; Mohieldain, Ali Ahmed; Csámer, Árpád; Satti, Albarra M.N.; Rózsa, Péter
Dátum:
2024
ISSN:
2352-9385
Megjegyzések:
The increasing global demand for barite, driven by its geological importance and various industrial applications, advises the scientific community to improve attempts to identify and explore its deposits in different geological settings. This boost in interest aims to ensure sustainable supply by locating new sources and better understanding the conditions in which barite forms. This study presents an integrated approach using multispectral (Landsat 8 & 9, Sentinel-2, and ASTER) and hyperspectral (PRISMA) remote sensing data, along with geophysical gravity data, to improve the localization of barite deposits. Several image processing methods, including false colour composites, principal component analysis, band ratios, minimum noise fraction, and spectral analysis, were employed for the discrimination of barite deposits, revealing their association with felsic rocks (referred to as group C). Additionally, lineament extraction was performed using the recent and advanced different filters like Tilt Angle Horizontal Gradient (TAHG) and Enhanced Horizontal Gradient Amplitude (EHGA) on Bouguer anomalies, highlighting the structural control of barite deposits by the D3 deformation phase. Field investigations were conducted to validate our findings. Based on these field observations, the integrated methodology successfully mapped the distribution of barite and its host rocks, resulting in an updated geological map for barite distribution that can be used in further exploration phases. We strongly recommend the adopted approach and the newly proposed image combinations for preliminary explorations of barite in similar arid terrains.
Tárgyszavak:
Természettudományok
Földtudományok
idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Barite
Remote sensing
Felsic rocks
Enhanced horizontal gradient amplitude (EHGA)
Bouguer anomalies
Megjelenés:
Remote Sensing Applications: Society and Environment. - 37 (2025), p. 1-27. -
További szerzők:
Shebl, Ali (1992-) (geológus)
Abdelkader, Mohamed M.
Mohieldain, Ali Ahmed
Csámer Árpád (1976-) (geológus)
Satti, Arshad Mehmod
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
2.
001-es BibID:
BIBFORM125955
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Diagenetic Evolution of the Wadi Halfa Oolitic Ironstone Formation (Formerly Nubian Sandstone), Northern Sudan / Abazar Daoud, Péter Rózsa
Dátum:
2024
Megjegyzések:
Clastic sediments of varying ages, types, and depositional environments, generally known as the ♭Nubian Sandstone Formation', overlay the Precam-brian basement complex rocks in Sudan, Libya, and Egypt. The Wadi Halfa Oolitic Ironstone Formation, part of this formation, spans over 500 km? near Nubian Lake in northern Sudan, bordering southern Egypt. This formation features alternating beds of shale, siltstone, and sandstone, marked by layer of oolitic ironstone and barite concretions, intercalated with ichnofossils and plant fossils spanning the Late Carboniferous, Permo-Triassic, and Lower Jurassic age, indicating different depositional environments. Petrographic analysis reveals that the formation's sandstone is composed of detrital framework grains, including monocrystalline and polycrystalline quartz, feldspars, lithic fragments, followed by iron oxides, clays, carbonates, micas, and heavy minerals. The barite concretions contain angular to very angular pure quartz grains, with monocrystalline quartz comprising 44% and polycrystalline quartz 20%. Barite, making up 42% of the cementing materi-al, sometimes penetrates and corrodes quartz grains. Based on mineral com-position, the sandstone is classified as quartzarenite (67%), sublithic arenite (21%), and subarkose (12%). Diagenetic processes have primarily reduced the original porosity through cementation rather than compaction.
Tárgyszavak:
Természettudományok
Földtudományok
előadáskivonat
könyvrészlet
Oolitic ironstone
Barite
Original Porosity
Compaction
Cementation.
Megjelenés:
Mediterranean Geosciences Union (MedGU) 4th annual meeting. - accepted for publication : - (2024), p. 1. -
További szerzők:
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
3.
001-es BibID:
BIBFORM125954
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Integrated Multi-Sensor Remote Sensing and Geophysical Data for Barite Potential Mapping in Ariab Districts, Northeast Sudan / Abazar Daoud, Ali Mohieldain, Mohamed Abdelkader, Ali Shebl, Aya Shereif, Albarra Satti, Péter Rózsa
Dátum:
2024
Megjegyzések:
Extensive scientific inquiries into barite have escalated due to increasing global demand, prompted by its resourceful applications in crucial industries and its association with mineralization of gold and copper. The current re-search utilizes a combination of multi-sensor approaches (Landsat 9 and PRISMA) along with the free satellite gravity data to optimize the detection and delineation of the barite deposit in the Sudanese part of the Nubian Shield. Techniques such as false color composites (FCC), principal compo-nent analysis (PCA), band ratios (BR), minimum noise fraction (MNF), Total Horizontal Gradient (THG), the Second Vertical Derivatives (SVD), and spectral analysis were utilized to distinguish lithological features, displaying the barite occur in association with acidic metavolcanic rocks within the Ari-ab district. Additionally, the gravity methods delineate structurally controlled barite mineralization associated with the north-east deformation phase. Our results were validated through comprehensive field investigations; the find-ings were exceptionally robust , enhancing the development of an updated map delineating additional prospective zones for barite deposits within the study area. The integrated geospatial, hyperspectral, and gravity data are strongly recommended for reconnaissance exploration of barite in other simi-lar regions.
Tárgyszavak:
Természettudományok
Földtudományok
előadáskivonat
könyvrészlet
Landsat 9
PRISMA
Total Horizontal Gradient
Second Vertical Derivatives
Barite
Megjelenés:
Mediterranean Geosciences Union (MedGU) 4th annual meeting. - accepted for publication : - (2024), p. 1. -
További szerzők:
Mohieldain, Ali Ahmed
Abdelkader, Mohamed M.
Shebl, Ali (1992-) (geológus)
Shereif, Aya S. (1994-) (Geologist)
Satti, Albarra
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
4.
001-es BibID:
BIBFORM124594
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Petrography and diagenesis of barite concretions from Wadi Halfa, Sudan / Abazar Mohamed Ahmed Daoud, Kadry Nasser Sediek, Mohamed Ahmed Rashed, Ahmed Mohamed Elsharief, Abdelaziz Mohamed Elamein, Péter Rózsa
Dátum:
2024
Megjegyzések:
During the detailed geological observation of the sedimentary outcrops around the region of Wadi Halfa in Northern Sudan, discoidal-shaped concretions of barite were found. The lithofacies of these sedimentary outcrops, ♭Wadi Halfa Formation', contain sediments of continental, glacial and marine environments including trough and planner cross bedded sandstone, fine and massive mudstone facies intercalated with some marine fossils marked by a thin layer of oolitic ironstone and large petrified tree trunks. The vertical lithofacies of barite concretions comprises fine to medium yellowish to grayish sandstone overlain by a poorly sorted pinkish coarse-grained sandstone layer which contains barite concretions varying in size and shape. The discoidal-shaped barite concretions were found penetrating the bedding planes of sandstone. The upper part of these concretions is associated with fine-grained sandstone, while the lower part corresponds to coarse-grained sandstone. The framework of the barite concretions is composed primarily of very angular to angular monocrystalline (43.7%) and polycrystalline (11.5%) quartz grains, smaller amount of fledspars and heavy minerals (1.5%). Barite serves as the main cementing material, constituting 42% of the composition. The average porosity of most samples is 3%. Detailed petrographic analysis suggests that their original porosity has been reduced by cementation (44.1%) rather than compaction processes (0.6-5.2%). However, the origin of the concretions and the source of the barium remains unresolved. Moreover, quartz grains of these concretions are highly pure, they show much higher purity than quartz occurring in the embedding sandstone. The barite in the study area may formed during the Permian era (250 million years ago) when Mediterranean ocean waters covered the northern part of Sudan. Barite precipitated and crystallized from seawater around the quartz grains similarly to Oklahoma (USA), Egypt, Morocco and Australia. Understanding the original sources of these concretions may guide the exploration for other metallic minerals and petroleum. Additionally, barite holds significant economic potential due to its variuos applications across different industries and engineering projects, including its use in shielding against radiation in high-radiation environments and its critical role in medical applications.
ISBN:
978-963-8321-61-9
Tárgyszavak:
Természettudományok
Földtudományok
előadáskivonat
könyvrészlet
Megjelenés:
Ahány kő, annyi történet 14. Kőzettani és Geokémiai Vándorgyűlés Előadás- és poszterkivonatok / szerk. Buday Tamás, Csámer Árpád, McIntosh Richard William, Molnár Kata, Virág Attila. - p. 32. -
További szerzők:
Sediek, Kadry N.
Rasheed, Mohammed
Elsharief, Ahmed M.
Elamein, Abdelaziz M.
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Szerző által megadott URL
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
5.
001-es BibID:
BIBFORM124593
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Landsat 8 and Sentinel 2 for Detecting Hydrothermal Barite Deposits in Red Sea Hills, Sudan / Abazar M. A. Daoud, Ali Ahmed Mohieldain, Abdelmajeed A. Elrasheed, Peter Rozsa
Dátum:
2024
Megjegyzések:
Barite rocks often occur as hydrothermal veins in association with gold, copper, lead, and silver mineralization within felsic rocks in Red Sea Hills. The present study used the integration of Landsat 8, Sentinel 2, and field observations for mapping hydrothermal massive barite deposits in the Ariab District, within the Red Sea Hills, Sudan. Different techniques include false color composites, principal component analysis, and band ratios for visible near-infrared (VNIR), shortwave infrared (SWIR), and thermal infrared (TIR) used for the detection of iron sulfate minerals (2/1) ? (5/4) in L8, silica-rich rocks (7/6), hydroxyl-bearing minerals (6/7), ferric (4/2) in L8 and (11/8A) in S2, and ferrous iron oxides (5/6), (B12/B8A) + (B3/B4) in L8 and S2 respectively. This primary research contributes to the advancement of remote sensing methods for mineral exploration and underscores the significance of satellite-based techniques in mapping barite deposits. For future research, we are supposed to use further integration of shortwave infrared of L8, S2, and thermal infrared ASTER with the PRISMA spectral analysis, airborne geophysical methods, and detailed field observations with detailed structural and mineralogical investigations for more accuracy.
ISBN:
978-963-490-619-3
Tárgyszavak:
Természettudományok
Földtudományok
tanulmány, értekezés
könyvrészlet
Barite
Landsat 8
Sentinel 2
iron sulfate minerals
silica-rich rocks
hydroxyl-bearing minerals
ferric and ferrous iron oxides
Megjelenés:
Az elmélet és a gyakorlat találkozása a térinformatikában XV. / szerk. Abriha-Molnár Vanda Éva. - p. 91-98. -
További szerzők:
Mohieldain, Ali Ahmed
Abdelmajeed, Adam Elrasheed Ali (1988-) (Geologist)
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Szerző által megadott URL
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
6.
001-es BibID:
BIBFORM124592
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Exploring Iron Ore and Barite Deposits through Multiscale Analysis: A Case Study in Wadi Halfa, North Sudan / Abazar M A Daoud, Mutwakil Nafi, Péter Rózsa
Dátum:
2024
Megjegyzések:
Within the framework of modern mineral exploration, particularly in conflict-susceptible regions, rapid and cost-effective remote sensing has become an available tool for geologists. This paper focuses on the examination of clastic sediments around the region of Wadi Halfa North Sudan, employing an innovative approach that integrates remote sensing, field observations, and petrographical analysis to identify iron ore and barite deposits. Utilization of image processing techniques such as band ratios (BR), false color composites (FCC) were applied for the detection of hydroxyl-bearing minerals, ferric, and ferrous iron oxides (B6/B7), (B4/B2), (B5/B6) and barite (B7/B6) respectively; four types of iron ore and barite with different distinct layers were detected and identified. Petrographical and chemical analysis of rock samples validate the remote sensing findings, indicating significant concentrations of iron ore (46.01% for Fe+2) and barite (63.9% for Ba+), respectively. The final geological map generated by composed bands R(B6/B7), G(B4/B3), and B(B5/B7), R(B6/B7), G(B4/B2), B(B4/B11) in Landsat 8 OLI and Sentinel S2 respectively reveals major geological variations between lithological units of different ages with new finding of another resources of iron ores around the study area. Results obtained from the combination of remote sensing and field observations provide valuable information for future exploration and assessment of these critical mineral resources, which are of significant economic importance for Sudan and the region and can be applied for similar areas in other arid semi-arid regions.
ISBN:
978-963-8161-23-9
Tárgyszavak:
Természettudományok
Földtudományok
előadáskivonat
könyvrészlet
Megjelenés:
54. Meeting of Young Geoscientists - 54. Ifjú Szakemberek Ankétja: Absztrakt kötet. - p. 18. -
További szerzők:
Mutwakil, Nafi
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Szerző által megadott URL
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
7.
001-es BibID:
BIBFORM124179
Első szerző:
Daoud Abazar Mohamed Ahmed (földtudományi kutató, geológus, geográfus)
Cím:
Relationship between petrography and geomechanical properties of the sandstone: A case study from Wadi Halfa, North Sudan / Daoud, Abazar M. A.; Abdelkader, Mohamed M.; Sediek, Kadry N.; Elsharief, Ahmed M.; Rashed, Mohamed A.; Elamein, Abdelaziz M.; Abdalrahiem, Khaled O.; Rózsa, Péter
Dátum:
2024
ISSN:
2062-0810 2063-4269
Megjegyzések:
The investigation of the effect of petrography and diagenetic features on the geomechanical properties of the sandstone and their relationship to rock failure are of vital importance for different construction projects. The present study involves analyzing multi-vertical lithofacies profiles around the region of Wadi Halfa, North Sudan. The sandstone is dominantly composed of monocrystalline quartz grains (60%) accompanied by some polycrystalline quartz, feldspars, lithic fragments, micas, and heavy minerals. Iron oxides are the main type of cementing materials (14%), with some (2%) of carbonates and clay minerals. The average porosity of all studied samples is 12%. The compressive strength ranges widely, influenced by weathering, grain size, cementing materials, and bedding planes. The uniaxial compressive strength is more influenced by wetting when the load is parallel to bedding planes. Sandstone anisotropy is suggested by a U-shaped curve, with lower values at 458 and higher values at 908 and 08. The geomechanical behavior of rocks masses in Wadi Halfa was evaluated through a combination of field and laboratory analyses which revealed a variable Rock Mass Rating (RMR) ranging from 58 to 92 and a Geological Strength Index (GSI) ranging from 33 to 61.
Tárgyszavak:
Természettudományok
Földtudományok
idegen nyelvű folyóiratközlemény hazai lapban
folyóiratcikk
sandstone
compressive strength
anisotropy
post-specimen failure
softness coefficient
RMRGSI
Megjelenés:
International Review of Applied Sciences and Engineering. - [Epub ahead of print] (2024), p. 1-17. -
További szerzők:
Abdelkader, Mohamed M.
Sediek, Kadry N.
Elsharief, Ahmed M.
Rasheed, Mohammed
Elamein, Abdelaziz M.
Abdalrahiem, Khaled O.
Rózsa Péter (1956-) (petrográfus)
Internet cím:
Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:
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