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Mapping the Alteration Zones for Uranium Exploration in Gabal Abu Garadi Area Central Eastern Desert, Egypt, Using Aster Data
Nehal Mohamed Soliman,
Moustafa Bayoumi Bayoumi,
Salem Mohamed Salem
Issue:
Volume 10, Issue 2, April 2021
Pages:
36-48
Received:
16 February 2021
Accepted:
15 March 2021
Published:
23 April 2021
Abstract: The integration of the ASTER image processing and the airborne spectrometric Gamma-Ray interpretation helped in identifying the types and illustrating the distributions of the probable sites for radioactive mineralization at the Gabal Abu Garadi area. Appling various techniques of image processing for Landsat OLI and ASTER satellite to discrimination the differently exposed rock units and extract major and minor structural lineaments. This study resulted that the ASTER VNIR-SWIR bands are effectively used for clarifying the sericite, kaolinite, chlorite, illite and hematite bearing alteration zones, whereas the ASTER TIR bands are most effective in delineation of the silica-rich zones which could be pathfinders for radioactive mineralization within the study area. The resultant alteration maps show good coincidence with the explored uranium sites and suggest further similar unexplored sites. The predominance of low eTh/eU= 1.31 indicates U mobilization and reveals that magmatic differentiation was not the sole process responsible for the concentration of these radioactive elements in the Abu Gradi area. Where the presence of adequate structures such as shear zones and fault planes facilitates the circulation of hydrothermal fluids and meteoric waters leading to mobilization and a redistribution of uranium. This paper could assist the principals of uranium exploration techniques.
Abstract: The integration of the ASTER image processing and the airborne spectrometric Gamma-Ray interpretation helped in identifying the types and illustrating the distributions of the probable sites for radioactive mineralization at the Gabal Abu Garadi area. Appling various techniques of image processing for Landsat OLI and ASTER satellite to discriminati...
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Estimation of Seismic Ground Motions and Attendant Potential Human Fatalities from a Scenario Earthquake on the Hsincheng Active Fault in Taohsin Area, Taiwan
Kun-Sung Liu,
Hsiang-Chi Huang
Issue:
Volume 10, Issue 2, April 2021
Pages:
49-63
Received:
12 April 2021
Accepted:
24 April 2021
Published:
8 May 2021
Abstract: The purpose of this study is to assess seismic hazards in the 29 administration districts of Taohsin area (Taoyuan City, Hsinchu County and Hsinchu City), Taiwan in the form of ShakeMaps as well as to estimate potential human fatalities from a scenario earthquake Mw 6.77 on the Hsincheng active fault in this area. The PGA contour map using historical seismic data and four active faults to calculate the ground motions shows that the areas where the PGA is greater than 400 gal are in the following regions: (1) Southwestern Longtan. (2) Southwestern Hukou, southern Sinfong, southeastern Sinpu, northern and central Jhubei, northern Guansi, central Cyonglin, central Jhudong, western Beipu, southern Baoshan and Emei. (3) The northeastern Bei District and the northern Dong District. Furthermore, the PGV contour map shows that the areas greater than 40cm/s is located in the central Jhubei, western Beipu, southern Baoshan, Emei, and northern and western Dong District of Hsinchu City. In addition, we calculate the probability of earthquake intensity show that the regions with the highest potential for earthquake hazards are located in the area surrounded by Beipu, Baoshan and Emei, as well as the area surrounded by Hukou, Sinfong, Jhubei, Bei Distruct and Xiangshan. The corresponding probability of earthquake intensity exceeding MMI VIII during the period of 50 years is above 35%. Finally, from estimation of potential human fatalities for a scenario earthquake on the Hsincheng fault, the fatalities are 367, 848 and 809 in Taoyuan City, Hsinchu County and Hsinchu City, respectively. Moreover, it is noted that potential fatalities increase rapidly for people above age 45. Total fatalities reach a high peak in age groups of 55–64. Especially, the area surrounded by Jhubei of Hsinchu County, Bei District and Dong District of Hsinchu City with both high population density and high site amplification factor for PGA and PGV, the local governments should be pay more attention on seismic hazard mitigation in this highly urbanized area with large number of buildings.
Abstract: The purpose of this study is to assess seismic hazards in the 29 administration districts of Taohsin area (Taoyuan City, Hsinchu County and Hsinchu City), Taiwan in the form of ShakeMaps as well as to estimate potential human fatalities from a scenario earthquake Mw 6.77 on the Hsincheng active fault in this area. The PGA contour map using historic...
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A Comparative Study on the Composition of the Clastic and the Parent Rock of the Source Area in the Yanchang Formation in the Longdong Area of the Ordos Basin
Issue:
Volume 10, Issue 2, April 2021
Pages:
64-69
Received:
21 April 2021
Accepted:
7 May 2021
Published:
14 May 2021
Abstract: Based on the data of element geochemistry, electron probe, tectonic attributes, etc., the composition of the clastic and parent rock in the source area was analyzed for the Yanchang Formation in Longdong area. Research shows that the Yanchang Formation includes single crystal quartz, polycrystalline quartz, bicyclic quartz, fragmented quartz, dust-rich turbid quartz, and wavy matte quartz. Different types of quartz come from different parent rocks in different areas of the basin. Feldspar mainly comes from Guanshan pluton, Cuihua mountain, Haiyuan, and Longxi intermediate acid biotite granite in the periphery of the basin. In the Yanchang Formation in the study area, most of the heavy minerals in the sandstone formed by the northeast provenance come from the metamorphic parent rock in the Yinshan area, while the heavy minerals in the sandstone formed by the southwest provenance are formed in the hydrothermal metamorphic parent rock. The content of heavy minerals varies greatly in different depositional stages, and the provenance direction of sandstone in different intervals and the type of parent rock in the source area vary. The cuttings particles have a long transport distance, fine particle size, little cuttings retention, poor stability of rock structure and composition, weak resistance to weathering, and low cuttings content.
Abstract: Based on the data of element geochemistry, electron probe, tectonic attributes, etc., the composition of the clastic and parent rock in the source area was analyzed for the Yanchang Formation in Longdong area. Research shows that the Yanchang Formation includes single crystal quartz, polycrystalline quartz, bicyclic quartz, fragmented quartz, dust-...
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