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Wadi Fatima Thin-Skinned Foreland FAT Belt: A Post Amalgamation Marine Basin in the Arabian Shield  [PDF]
Zakaria Hamimi, Mohamed Matsah, Mohamed El-Shafei, Abdelhamid El-Fakharani, Abdulrahman Shujoon, Majid Al-Gabali
Open Journal of Geology (OJG) , 2012, DOI: 10.4236/ojg.2012.24027
Abstract: Wadi Fatima fold-thrust (FAT) belt is a distinctive foreland FAT belt in the Arabian-Nubian Shield (ANS) involving unmetamorphosed to slightly metamorphosed sedimentary sequence of Fatima Group, deposited over a metamorphic/igneous basement, comprising ortho-amphibolites, orthoand para-schists (with chaotic unmappable blocks of marbles, pyroxenites and metagabbros), older granite (773 ± 16 Ma) and younger granite. The basement exhibits structural fabrics, such as attenuated tight isoclinal folds, sheared-out hinges, NE-SW penetrative foliation and subhorizontal stretched and mineral lineations, related to an oldest prominent dextral shearing phase affected the main Wadi Fatima during the Neoproterozoic. In Wadi Fatima FAT belt, the style of deformation encompasses flexural-slip folding forming mesoscopicand map-scales NE to ENE plunging overturned antiforms and synforms, and a thrust duplex system bounded by floor thrust and sole thrust (basal detachment) dipping gently towards the hinterland (SE to SSE direction) and rises stratigraphically upwards towards the foreland. Such style is affiliated to thin-skinned deformation. Several lines of evidence, such as geometry of interacting outcropand map-scale folds and thrusts, patterns of thrust displacement variations and indications for hinge migration during fold growth, strongly suggest that folding and thrusting in Wadi Fatima FAT belt are geometrically and kinematically linked and that thrusting initiated as a consequence of folding (fold-first kinematics). Thrusts frequently show flat-ramp-flat geometry, and every so often give an impression that they are formed during two main sub-stages; an older sub-stage during which bedding sub-parallel thrusts were formed, and a younger sub-stage which generated younger ramps oblique to bedding. Thrust ramps with SE to SSE dipping regularly show sequential decrease in dip or inclination (due to piggy-back imbrication) into their transport direction which is proposed to be towards NW to NNW. Evidence indicating this transport direction of Wadi Fatima FAT belt embrace NW to NNW oriented stretching lineations recorded along thrust planes, NW to NNW folding vergence, and diminishing of the intensity of deformation and thrust stacking and imbrication from SE to NW; i.e. from hinterland to foreland. The tectonic transport vector is congruent with the mean orientation of slickenline striae formed by layer-parallel slipping along folded bedding planes. The mean orientation of slickenline lineations, after their host beds were rotated to horizontal about their
Application of SASW and MASW to buried fault detection
SASW及MASW方法在隐伏断层探测中的应用

贾辉,何正勤,叶太兰
地球物理学进展 , 2010,
Abstract: 针对地壳浅部介质横向变化大的特点,用瞬态瑞利波SASW与MASW方法对河北夏垫断裂进行了探测与数据处理分析.分别用时间域互相关法和频率域f-k分析法提取频散曲线,然后进行反演得到横波速度结构.实验结果表明瞬态瑞利波法在应用中便捷、灵活,对于探测地表介质中非均匀异常体及断裂向浅部的延伸情况具有独特的应用前景.
G-WADI—the first decade
W. Mike Edmunds,Ramasamy Jayakumar,Anil Mishr,Abdin Salih,Soroosh Sorooshian,Howard S. Wheater,William Logan
寒旱区科学 , 2013,
Abstract: The G-WADI network by UNESCO promotes the global capacity for management of water resources in arid and semi-arid areas. The primary aim has been to build a comprehensive global network to promote regional and international cooperation so as to increase knowledge and improve management practices through the sharing of information. The G-WADI objectives and achievements of the past 10 years are reviewed. A number of key initiatives have been implemented––the formation of five regional networks, the creation of a central G-WADI web site, promotion of near-real-time rainfall distribution software enhanced by the inclusion of satellite based precipitation estimations, as well as workshop and web-based activities on chemical and isotopic tracers and on rain water harvesting. Two workshops on surface and on groundwater modeling, supported by publications have been held in India and China. The Asian G-WADI network remains very active, but activities in the other three regions are developing (Africa, Arab Region, Latin America and the Caribbean).
Implementing VoIP over Fatima Jinnah Women University
Ammara Asif,Ammara Asif,Tahira Mahboob
International Journal of Computer Science Issues , 2011,
Abstract: Working people employee the use of technology in such very effective natural ways that permit them to do what they want: they can communicate with anyone as per need, in the time and space that suits them the best. Easily accessible and user-friendly, collaboration tools allow them to explore, share, engage, and connect with people and content in meaningful ways that help them learn. Traditional telephony carriers use circuit switching for carrying voice traffic. Circuit switching was designed for voice from the outset; hence it carries voice in an efficient manner. However it is an expensive solution. Nowadays people want to talk much more on phone, but they also want to communicate in a myriad of other ways - through e-mail, instant messaging, video, the World Wide Web, etc. Circuit switching is not suitable for this new world of multimedia communication. Therefore, in this paper a solution is proposed to implement scalable VOIP system over Fatima Jinnah University that will lead to better Quality of service and facilitates enhanced communication
Urban Sprawl in Wadi Goss Watershed (Jeddah City/Western Saudi Arabia) and Its Impact on Vulnerability and Flood Hazards  [PDF]
Ashi Azzam, Atef Belhaj Ali
Journal of Geographic Information System (JGIS) , 2019, DOI: 10.4236/jgis.2019.113023
Abstract: Today, climate change imposes enormous challenges on a global scale. The interactions of the balances between the need for development, population growth, massive urbanization generate a negative impact on the presence of these climate changes. One of the direct consequences of these changes is the phenomenon of flash floods, a phenomenon that hit the city of Jeddah (city located in west of Saudi Arabia) twice, one in 2009 and the other in 2011, causing significant human and material damage. Floods are considered as a direct result of the combination of extreme weather and hydrological phenomena; in most cases, the magnitude of these floods is magnified by anthropogenic factors, which increases the risk. According to the risk triangle, risk is defined as a probabilistic function that depends on three essential elements: exposure, vulnerability and hazard. If any of these three elements undergo growth the risk also does so and vice versa. Exposure and vulnerability will depend on the presence of human activities in the study area. This study is conducted on the Wadi Goss watershed as it was one of the most violent basins during the 2009 and 2011 floods. Indeed, we present in this study the extent of the urban extension in the Wadi Goss watershed, since 1984 to days and this by the using Landsat images. Given the nature of the study area, we present a method based on the calculation of various indices followed by a classification operation in order to define the urbanized zones inside the Wadi Goss watershed and then estimate the urban sprawl inside the watershed. We also present in this paper, the characteristics of the watershed as well as the evolution of the urbanized areas exposed to the phenomenon of floods and their contribution to the changes of the hydrological behavior of the basin, and to increase the evolution of the risk of the floods. We have shown through this study that the urban footprint has increased from 90 hectares in 1985 to 850 hectares in 2015. This urban footprint represents 12% of the total area of the watershed. Most of the urban evolution was operated on the wadi area with a concentration in the western part of the basin and especially at its outlet.
Vegetation Cover Density and Land Surface Temperature Interrelationship Using Satellite Data, Case Study of Wadi Bisha, South KSA  [PDF]
Amalyahya Alshaikh
Advances in Remote Sensing (ARS) , 2015, DOI: 10.4236/ars.2015.43020
Abstract: The aim of this study is to identify the relationship between Vegetation Cover (VC) and the land Surface Temperature (LST), using satellite data of Wadi Bisha, south the Kingdome of Saudi Arabia (KSA). The Landsat 7 Thematic Mapper (ETM) thermal band (band 6) was used for calculating the (LST) values. The near-infrared (NIR) and red band (bands 3 and 4 respectively) were used for estimating the vegetation cover. ERDAS Imagine 9.3 and ArcGIS 10.2 were used in the current study. The results of the study show that the increase of vegetation cover (VC) coincides with decrease of (LST), while the decrease in vegetation cover is linked with increase of (LST). It was found that there was no vegetation observed in areas practiced the highest temperature of 49℃, while areas of lowest temperature of 28℃ were characterized by dense vegetation cover. Thus, a quite significant correlation is approved between the (VC) and the (LST), based on the validation of (50) locations. It was concluded that availability and continuity of Satellite remote sensing data was required for elaborating a continuous monitoring of vegetation cover conditions and mapping was recommended in Wadi Bisha. Operational monitoring is recommended to ensure the adoption of flexible land cover validation protocols.
Hydrogeology of Wadi Qudaid Area, Northeast Jeddah, West Central Arabian Shield, Saudi Arabia  [PDF]
Abdullah R. Sonbul, Mohammed A. Sharaf, Ali A. Mesaed
Open Journal of Geology (OJG) , 2017, DOI: 10.4236/ojg.2017.712117
Abstract: The study area is a part of the Arabian Shield rocks of west central part of Saudi Arabia (150 km to the northeast of Jeddah). Geologically, the study area comprises five main geologic units i.e. 1) Layered basic volcanics and related volcaniclastics which are composed mainly from intercalated basalts and andesites and the related volcaniclastic derivatives, 2) Acidic volcanics and related volcaniclastics which are composed from layered and laminated dark and light acidic to intermediate igneous rocks, quartz and chert and marbles, 3) The Tertiary sedimentary succession which of volcaniclastic red beds and the intercalated clays; 5) Tertiary volcanics of Harrart, and 4) The Quaternary wadi fill deposits which are composed from friable pebble supported conglomerates, sandstones and clays. Hydrogeologically, the groundwater aquifer of Wadi Qudaid is present mainly in two main horizons i.e. i) unconfined shallow aquifer (13 - 37 m) within the well porous and permeable conglomerates of the Quaternary Wadi deposits, ii) The deep confined aquifer of the bedded tuffaceous sandstones and mudstone of the Tertiary sedimentary succession of Ash Shumaysi Formation. The water samples are analyzed for major elements i.e. Ca, Mg, Na, Cl, SO4, HCO3 and the results show the normal content of these elements. The study related the addition and depletion of many elements during the running trip of the groundwater from the northeast (recharge area) to the southwest (downstream) area.
Evaluating the Rate of Stone Art Deterioration in Wadi Maghara and Wadi Mukattab, Sinai, Egypt  [PDF]
Sayed HEMEDA,Walid ALGHAREB
International Journal of Conservation Science , 2012,
Abstract: One of the key reasons for the status of Wadi Maghara and Wadi Mukattab as World Heritage Sites is the abundance of stone art present there. Unfortunately, in time, much of the stone art heritage in the two archaeological sites was lost, due to natural stone weathering processes, to static and dynamic actions and lately, due to the lack of preservation measures and to the action of people. That fragile art heritage is non-renewable and, therefore, it requires specialized management. Several stone facades in Wadi Maghara have embossed inscriptions of early rulers of Egypt, that document their expeditions to mine precious minerals, primarily turquoise and copper, that were found in the area. Wadi Mukattab (south of Wadi Maghara) is the valley of inscriptions. Over a distance of 3 km along this valley inscriptions can be found on the mountain rocks that have mostly been made by Nabateans (2nd and 3rd Century) but also by others, such as pilgrims, soldiers, merchants, throughout the centuries. In our case study, inscriptions from specific study areas were analyzed by using SEM, polarizing microscope, XRD, SEM with EDX, DTA-TGA, Grain Size Distribution, Pore Media Characterization and some stone samples were tested in the stone mechanics laboratory, to determine the physical and mechanical characteristics of the stone with carved inscriptions. Digital photographs were taken, with Geographic Information Systems software. Older images were compared with more recent ones and in order to classify and quantify the amount of deterioration that occurred over time. Various methodologies were applied to classify the images, and it was found that manual digitizing provided the best means for quantifying the amount of deterioration. Results showed that the damage was primarily caused due to the instability of stone structures, because of the extensive jointing and rock fall gravity, due to dynamic actions and the granular disaggregation of the stone surface. The methodology used in this study can be utilized to evaluate the rate of decay of stone art and therefore a useful tool for determining priorities with regard to the conservation of the Wadi Maghara and Wadi Mukattab sites. In addition, the rate of deterioration is useful in evaluating and quantifying the contribution of stone weathering to landscape evolution.
The impact of Ty3-gypsy group LTR retrotransposons Fatima on B-genome specificity of polyploid wheats
Elena A Salina, Ekaterina M Sergeeva, Irina G Adonina, Andrey B Shcherban, Harry Belcram, Cecile Huneau, Boulos Chalhoub
BMC Plant Biology , 2011, DOI: 10.1186/1471-2229-11-99
Abstract: FISH analysis of a BAC clone (BAC_2383A24) initially screened with Spelt1 repeats demonstrated its predominant localisation to chromosomes of the B-genome and its putative diploid progenitor Aegilops speltoides in hexaploid (genomic formula, BBAADD) and tetraploid (genomic formula, BBAA) wheats as well as their diploid progenitors. Analysis of the complete BAC_2383A24 nucleotide sequence (113 605 bp) demonstrated that it contains 55.6% TEs, 0.9% subtelomeric tandem repeats (Spelt1), and five genes. LTR retrotransposons are predominant, representing 50.7% of the total nucleotide sequence. Three elements of the gypsy LTR retrotransposon family Fatima make up 47.2% of all the LTR retrotransposons in this BAC. In situ hybridisation of the Fatima_2383A24-3 subclone suggests that individual representatives of the Fatima family contribute to the majority of the B-genome specific FISH pattern for BAC_2383A24. Phylogenetic analysis of various Fatima elements available from databases in combination with the data on their insertion dates demonstrated that the Fatima elements fall into several groups. One of these groups, containing Fatima_2383A24-3, is more specific to the B-genome and proliferated around 0.5-2.5 MYA, prior to allopolyploid wheat formation.The B-genome specificity of the gypsy-like Fatima, as determined by FISH, is explained to a great degree by the appearance of a genome-specific element within this family for Ae. speltoides. Moreover, its proliferation mainly occurred in this diploid species before it entered into allopolyploidy.Most likely, this scenario of emergence and proliferation of the genome-specific variants of retroelements, mainly in the diploid species, is characteristic of the evolution of all three genomes of hexaploid wheat.Transposable elements (TEs) of various degrees of reiteration and conservation constitute a considerable part of wheat genomes (80%). TEs are a rapidly evolving fraction of eukaryotic genomes and the main contributors to ge
Evaluation of Groundwater Quality and its Recharge by Isotopes and Solute Chemistry in Wadi Malal, Al-Madinah Al-Munawarah, Saudi Arabia  [PDF]
Omar. A. Al-Harbi,Ghulam Hussain,M. Mujtaba Khan,Mohammaed A. Moallim
Pakistan Journal of Biological Sciences , 2006,
Abstract: The present study was conducted to determine groundwater chemistry, ascertain quality of water for various uses (domestic and agriculture) and define recharge sources of environmental isotopes in Wadi Malal, Al-Madinah Al-Munawarah, Saudi Arabia. Evaluation of water quality revealed that salinity and nitrate concentration are much higher than the established standards for various uses (so to say: irrigation and drinking etc.). Generally, the groundwater has been salinized by the equilibrium of infiltrated rainwater with slight soluble minerals in the regolith and evapoconcentration of groundwater that has been used for irrigation. Well waters in Wadi Malal along its flow path are too saline and the nitrate levels are too high to be used as drinking water. The salinity and sodicity levels in about 80% of the surveyed well waters are sufficiently high, when used for irrigation, to pose constraints on soil, crop and water management. Based on the concentration of the environmental isotopes (Deuterium and Oxygen-18) coupled with different ratios of NO3/Cl and HCO3/Cl, the primary source of the groundwater is rainfall that has occurred during the last 100-200 years with slight fractionation process in the water system.
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