Mapping Structurally Controlled Alterations Sparked by Hydrothermal Activity in the Fatira–Abu Zawal Area, Eastern Desert, Egypt     

Mohamed BADAWI  Mahmoud ABDELATIF  Ali SHEBL  Farid MAKROUM  Ahmed SHALABY  Norbert NEMETH 《《地质学报》英文版》2023,97(2):662-680

The Eastern Desert of Egypt suffered a protracted period of deformation triggered by cratonization of the new juvenile crust known as the Arabian Nubian Shield (ANS), which has been proposed for potential gold discoveries associated with the corresponding tectonic event. The Fatira area, on the border of Egypt''s Northern and Central Eastern Deserts, is covered with metavolcanic rocks twisted by a dextral relocation of the Fatira Shear Zone (FSZ) relative to the Barud magmatic body. The recent study evaluated many deformed post-orogenic granitic intrusions and felsite dikes associated with promising mineralization localities, notably orogenic gold deposits. The combination of various field observations and remote sensing data, followed by the analysis of aeromagnetic enhanced maps, allowed the differentiation of distinct lithologies, structural features, and hydrothermal alterations in the study area. Additionally, the integrated results obtained from the different interpretation techniques are utilized to identify and confirm the previously supposed mineralized localities in the Fatira and Abu Zawal areas and predict other matched localities. The final ASTER, Sentinel 2 hydrothermal alteration, and orientation entropy heat maps demonstrate the association between these mineralized regions and major structures related to the FSZ late stage of deformation rather than other structures studied throughout the area of interest.  相似文献   

Collinearity assessment of geocentre coordinates derived from multi-satellite SLR data     

Ciprian B. Spatar  Philip Moore  Peter J. Clarke 《Journal of Geodesy》2015,89(12):1197-1216

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Comparison of low-carbon pathways for California     

Geoffrey M. Morrison  Sonia Yeh  Anthony R. Eggert  Christopher Yang  James H. Nelson  Jeffery B. Greenblatt  Raphael Isaac  Mark Z. Jacobson  Josiah Johnston  Daniel M. Kammen  Ana Mileva  Jack Moore  David Roland-Holst  Max Wei  John P. Weyant  James H. Williams  Ray Williams  Christina B. Zapata 《Climatic change》2015,131(4):545-557

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Unprecedented recent warming rate and temperature variability over the east Tibetan Plateau inferred from Alpine treeline dendrochronology     

Shi  Chunming  Masson-Delmotte  Valérie  Daux  Valérie  Li  Zongshan  Carré  Matthieu  Moore  John C. 《Climate Dynamics》2015,44(5-6):1367-1379

Climate Dynamics - Despite instrumental records showing recent large temperature rises on the Tibetan Plateau (TP), only a few tree-ring temperature reconstructions do capture this warming trend....  相似文献   

Geometric calculation of view factors for stream surface radiation modelling in the presence of riparian forest          下载免费PDF全文

R. D. Moore  J. A. Leach  J. M. Knudson 《水文研究》2014,28(6):2975-2986

Many efforts to model stream temperature by using an energy budget approach have not accounted for view factors in modelling stream surface radiative exchanges, used informal approaches for computing them, or relied on calibration, which is not applicable for prediction at unmonitored sites or for predicting the effects of changes in riparian vegetation. In this paper, equations are derived for calculating view factors on the basis of geometric considerations for streams with and without riparian forest. The solutions can accommodate vegetation overhanging the stream surface. Example calculations illustrate the substantial variability of view factors across the stream width, which has implications for the estimation of view factors from point‐scale radiation measurements over the stream surface, and the important influence of overhanging vegetation on view factors for narrow streams. View factors computed from the geometric model agreed well with view factors computed from hemispherical photography for streams ranging from 1 to almost 50 m wide, indicating that the model appears to be reasonably robust to deviations from the simplified geometry assumed by the model. In addition to their use in modelling stream surface energy exchanges, the solutions could also be adapted for application to energy balance and microclimate modelling in linear forest openings, such as seismic lines used in oil and gas exploration. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Late‐summer thermal regime of a small proglacial lake     

J. Richards  R. D. Moore  A. L. Forrest 《水文研究》2012,26(18):2687-2695

This study was motivated by an interest in understanding the potential effects of climate change and glacier retreat on late summer water temperatures in alpine areas. Fieldwork was carried out between July and September 2007 at Place Lake, located below Place Glacier in the southern Coast Mountains of British Columbia. Place Lake has an area of 72 000 m², a single inlet and outlet channel, and an approximate residence time of 4 days. Warming between the inlet and outlet of the lake ranged up to 3 °C and averaged 1.8 °C, which exceeds the amount of warming that occurred over the 1 km reach of Place Creek between the lake outlet and tree line. Over a 23‐day period, net radiation totalled about 210 MJ·m^–2, with sensible heat flux adding another 56 MJ m^‐2. The latent heat flux consumed about 8% of the surface heat input. The dominant heat sink was the net horizontal advection associated with lake inflow and outflow. Early in the study period, temperatures between the surface and 6‐m depth were dominantly at or above 4 °C and were generally neutral to thermally stable, whereas temperatures decreased with depth below 6 m and exhibited irregular sub‐diurnal variations. The maximum outflow temperature of almost 7 °C occurred in this period. We hypothesize that turbidity currents associated with cold, sediment‐laden glacier discharge formed an underflow and influenced temperatures in the deeper portion of the lake but did not mix with the upper layers. Later in the study period, the lake was dominantly well mixed with some near‐surface stability associated with nocturnal cooling. Further research is required to examine the combined effects of sediment concentrations and thermal processes on mixing in small proglacial lakes to make projections of the consequences of glacier retreat on alpine lake and stream temperatures. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Stream temperature dynamics in two hydrogeomorphically distinct reaches     

J. A. Leach  R. D. Moore 《水文研究》2011,25(5):679-690

The objective of this study was to analyse stream temperature variability during summer in relation to both surface heat exchanges and reach‐scale hydrology for two hydrogeomorphically distinct reaches. The study focused on a 1·5‐km wildfire‐disturbed reach of Fishtrap Creek located north of Kamloops, British Columbia. Streamflow measurements and longitudinal surveys of electrical conductivity and water chemistry indicated that the upper 750 m of the study reach was dominated by flow losses. A spring discharged into the stream at 750 m below the upper reach boundary. Below the spring, the stream was neutral to losing on three measurement days, but gained flow on a fourth day that followed a rain event. Continuous stream temperature measurements typically revealed a downstream warming along the upper 750 m of the study reach on summer days, followed by a pronounced cooling associated with the spring, with little downstream change below the spring. Modelled surface energy exchanges were similar over the upper and lower sub‐reaches, and thus cannot explain the differences in longitudinal temperature patterns. Application of a Lagrangian stream temperature model provided reasonably accurate predictions for the upper sub‐reach. For the lower sub‐reach, accurate prediction required specification of concurrent flow losses and gains as a hydrological boundary condition. These findings are consistent with differences in the hydrogeomorphology of the upper and lower sub‐reaches. The modelling exercise indicated that substantial errors in predicted stream temperature can occur by representing stream‐surface exchange as a reach‐averaged one‐directional flux computed from differences in streamflow between the upper and lower reach boundaries. Further research should focus on reliable methods for quantifying spatial variations in reach‐scale hydrology. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Report of Excursions Arranged by the North-East Lancashire Group, 1924     

E.W.J. Moore 《Proceedings of the Geologists' Association. Geologists' Association》1925,36(2):185-188

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Distribution of diffuse flow megafauna in two sites on the Eastern Lau Spreading Center, Tonga     

Elizabeth L. Podowski  Tom S. Moore  Kevin A. Zelnio  George W. Luther III  Charles R. Fisher 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(11):2041-2056

Hydrothermal vent environments are characterized by large gradients of toxic chemicals and high temperatures, which play a significant role in defining species’ distributions. We used high-resolution imagery and spatially explicit in-situ physico-chemical measurements analyzed within a Geographic Information System (GIS) in order to characterize the spatial relations among different groups of megafauna, temperature, and chemistry within two discrete vent communities (40 and 50 m²) on the Eastern Lau Spreading Center (ELSC). Chemical (sulfide and O₂ concentrations) and temperature data were obtained from approximately 75 different locations within each community using in-situ instruments. All data were integrated into a GIS, which served as a visualization tool and enabled the data to be analyzed in a spatial context. Our results confirm the importance of abiotic variables in defining the distributions of some fauna and elucidate several biological associations that are consistent between the two communities. The provannid snail, Alviniconcha spp., appears to actively avoid temperatures above 32–46 °C and/or sulfide concentrations exceeding approximately 260 μM. Slightly higher average sulfide concentrations and temperatures were measured among aggregations of Ifremeria nautilei compared to aggregations of the mussel Bathymodiolus brevior; however, the presence of mixed aggregations of the two species indicates an overlap in requirements. The brachyuran crab, Austinograea spp., was consistently observed directly on symbiont-containing species, particularly Alviniconcha spp. The solitary snail, Eosipho desbruyeresi, was rarely observed on biological substrata, but was often (60% of its population at the most active site) within 5 cm of symbiont-containing fauna, indicating a tolerance and preference for proximity to areas of high productivity. Densities and coverage of species differed substantially between the two communities despite high species overlap. Symbiont-containing species covered much larger areas at the more hydrothermally active site, ABE1, while shrimp and anemones occurred in relatively higher densities within the less-active site, TM1. This is the first study to thoroughly characterize realized distributions of megafauna at vent sites along the ELSC.  相似文献   

Development of data infrastructure to support scientific analysis for the International GNSS Service   总被引：1，自引：1，他引：0  

C. Noll  Y. Bock  H. Habrich  A. Moore 《Journal of Geodesy》2009,83(3-4):309-325

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