Sequence Stratigraphy and Rudist Facies Development of the Upper Barremian‐Lower Cenomanian Platform,Northern Sinai,Egypt     

Yasser SALAMA  Michael GRAMMER  Shaban SABER  Soheir EL-SHAZLY  Gouda ABDEL-GAWAD 《《地质学报》英文版》2018,92(1):286-310

The Lower Cretaceous sections in northern Sinai are composed of the Risan Aneiza (upper Barremian-middle Albian) and the Halal (middle Albian-lower Cenomanian) formations. The facies reflect subtle paleobathymetry from inner to outer ramp facies. The inner ramp facies are peritidal, protected to open marine lagoons, shoals and rudist biostrome facies. The inner ramp facies grade northward into outer ramp deposits. The upper Barremian-lower Cenomanian succession is subdivided into nine depositional sequences correlated with those recognized in the neighbouring Tethyan areas. These sequences are subdivided into 19 medium-scale sequences based on the facies evolution, the recorded hardgrounds and flooding surfaces, interpreted as the result of eustatic sea level changes and local tectonic activities of the early Syrian Arc rifting stage. Each sequence contains a lower retrogradational parasequence set that constituted the transgressive systems tracts and an upper progradational parasequence set that formed the highstand systems tracts. Nine rudist levels are recorded in the upper Barremian through lower Cenomanian succession at Gabal Raghawi. At Gabal Yelleg two rudist levels are found in the Albian. The rudist levels are associated with the highstand systems tract deposits because of the suitability of the trophic conditions in the rudist-dominated ramp.  相似文献   

Current Status and Future Challenges of Weather Radar Polarimetry: Bridging the Gap between Radar Meteorology/Hydrology/Engineering and Numerical Weather Prediction     

Guifu ZHANG  Vivek N.MAHALE  Bryan J.PUTNAM  Youcun QI  Qing CAO  ANDrew D.BYRD  Petar BUKOVCIC  Dusan S.ZRNIC  Jidong GAO  Ming XUE  Youngsun JUNG  Heather D.REEVES  Pamela L.HEINSELMAN  AlexANDer RYZHKOV  Robert D.PALMER  Pengfei ZHANG  Mark WEBER  Greg M.MCFARQUHAR  Berrien MOORE III  Yan ZHANG  Jian ZHANG  J.VIVEKANANDAN  Yasser AL-RASHID  Richard L.ICE  Daniel S.BERKOWITZ  Chong-chi TONG  Caleb FULTON  Richard J.DOVIAK 《大气科学进展》2019,36(6):571-588

After decades of research and development, the WSR-88 D(NEXRAD) network in the United States was upgraded with dual-polarization capability, providing polarimetric radar data(PRD) that have the potential to improve weather observations,quantification, forecasting, and warnings. The weather radar networks in China and other countries are also being upgraded with dual-polarization capability. Now, with radar polarimetry technology having matured, and PRD available both nationally and globally, it is important to understand the current status and future challenges and opportunities. The potential impact of PRD has been limited by their oftentimes subjective and empirical use. More importantly, the community has not begun to regularly derive from PRD the state parameters, such as water mixing ratios and number concentrations, used in numerical weather prediction(NWP) models.In this review, we summarize the current status of weather radar polarimetry, discuss the issues and limitations of PRD usage, and explore potential approaches to more efficiently use PRD for quantitative precipitation estimation and forecasting based on statistical retrieval with physical constraints where prior information is used and observation error is included. This approach aligns the observation-based retrievals favored by the radar meteorology community with the model-based analysis of the NWP community. We also examine the challenges and opportunities of polarimetric phased array radar research and development for future weather observation.  相似文献   

Five dimensional Bianchi type-I string cosmological model in Brans-Dicke theory     

Ghanshyam Singh Rathore  Kirti Mandawat 《Astrophysics and Space Science》2009,321(1):37-41

A Bianchi type-I string cosmological model in Brans-Dicke theory in five dimension space-time has been investigated. For the determinate solution it has been assumed that the sum of energy density and tension density of the cosmic string dust source vanishes. Some physical and kinematical parameters are also discussed.  相似文献   

Veterinary antibiotics contamination in water, sediment, and soil near a swine manure composting facility   总被引：5，自引：0，他引：5  

Yasser M. Awad  Sung-Chul Kim  Samy A. M. Abd El-Azeem  Kye-Hoon Kim  Kwon-Rae Kim  Kangjoo Kim  Choong Jeon  Sang Soo Lee  Yong Sik Ok 《Environmental Earth Sciences》2014,71(3):1433-1440

Antibiotics have been commonly used to prevent animal diseases and promote livestock productivity. However, its release into the surrounding environments leads to ecological disturbance and risks to human health. This study was conducted to monitor the occurrence and seasonal variations of antibiotics in water, sediment, and soil close to a swine manure composting facility, Korea. Various types of antibiotics such as tetracyclines (TCs) including tetracycline, chlortetracycline, and oxytetracycline, and sulfonamides (SAs) including sulfamethazine, sulfamethoxazole, and sulfathiazole were measured by the high-performance liquid chromatography-tandem mass spectrometry via a solid-phase extraction. In the results it was identified that the variations of measured antibiotics’ concentrations in water, sediment, and soil are depending on the season. The observed concentration levels of TCs were higher in winter than in summer season, indicating that the low temperature is a parameter attributing to interruption of its degradation in water, sediment, and soil. The concentration levels of SAs were significantly higher than those of TCs and in general, all measured antibiotics’ concentrations were also in general higher in Korea when compared to those in other countries. The long-term monitoring of antibiotics’ residues in aquatic and terrestrial environments is necessary.  相似文献   

Evaluating factors responsible for contrasting signature of wasteland development in northern and southern Ganga Plains (Bihar State,India) with focus on waterlogging     

Suraj Kumar Singh  A. C. Pandey  V. S. Rathore  M. S. Nathawat 《Arabian Journal of Geosciences》2014,7(10):4175-4190

The present study provides assessment of wasteland development in Bihar State based on satellite data. Wasteland covers 6.90 % (6,501 km²) of the state area and exhibits dominance of waterlogged areas in North Bihar (25.28 %) and scrubland (26.61 %) in South Bihar. The waterlogged areas in the state are dominantly associated with northern Bihar plains (94 %) with minor development (6 %) in southern Bihar plains. Such unequal distribution of waterlogged land areas in northern and southern Bihar plains is largely governed by high cumulative discharge generated in the large catchment area in Himalayan mountain ranges in the upland areas of northern Bihar plains in contrast to low cumulative discharge generated within small catchments in the Chota Nagpur Plateau in the southern Bihar plains. It is evaluated that the relief and groundwater level define the primary controlling factors, whereas rainfall, watershed area, and upland/plain ratio exert secondary control. Lower relief areas with high rainfall exhibit high soil moisture thereby inducing conditions of waterlogging. The study signifies the potential of satellite image-based evaluation of waterlogging through the use of Digital Elevation Model, Tropical Rainfall Measuring Mission-based rainfall measurement, and temporal waterlogging assessment together with other terrain parameters for conceptual understanding of waterlogging in northern Bihar plains.  相似文献   

Site suitability analysis for khair(ACACIA CATECHU) in part of doon valley using geoinformatics     

Puneet Dwivedi  S. P. S. Kushwaha  S. Nandy  C. S. Rathore 《Journal of the Indian Society of Remote Sensing》2006,34(2):187-191

  相似文献   

Regional setting and characteristics of the Neoproterozoic Wadi Hamama Zn–Cu–Ag–Au prospect: evidence for an intra-oceanic island arc-hosted volcanogenic hydrothermal system     

Yasser Abd El-Rahman  Adel A. Surour  Abdel Hamid W. El-Manawi  Abdel-Monem A. El-Dougdoug  Sayed Omar 《International Journal of Earth Sciences》2015,104(3):625-644

  相似文献   

Effects of Climate Change on Rice Production in the Tropical Humid Climate of Kerala, India     

S. A. Saseendran  K. K. Singh  L. S. Rathore  S. V. Singh  S. K. Sinha 《Climatic change》2000,44(4):495-514

The CERES-Rice v3. crop simulation model, calibrated and validated for its suitability to simulate rice production in the tropical humid climate Kerala State of India, is used for analysing the effect of climate change on rice productivity in the state. The plausible climate change scenario for the Indian subcontinent as expected by the middle of the next century, taking into account the projected emissions of greenhouse gases and sulphate aerosols, in a coupled atmosphere-ocean model experiment performed at Deutsches Klimarechenzentrum, Germany, is adopted for the study. The adopted scenario represented an increase in monsoon seasonal mean surface temperature of the order of about 1.5°C, and an increase in rainfall of the order of 2 mm per day, over the state of Kerala in the decade 2040–2049 with respect to the 1980s. The IPCC Business-as-usual scenario projection of plant usable concentration of CO₂ about 460 PPM by the middle of the next century are also used in the crop model simulation. On an average over the state with the climate change scenario studied, the rice maturity period is projected to shorten by 8% and yield increase by 12%. When temperature elevations only are taken into consideration, the crop simulations show a decrease of 8% in crop maturity period and 6% in yield. This shows that the increase in yield due to fertilisation effect of elevated CO₂ and increased rainfall over the state as projected in the climate change scenario nearly makes up for the negative impact on rice yield due to temperature rise. The sensitivity experiments of the rice model to CO₂ concentration changes indicated that over the state, an increase in CO₂ concentration leads to yield increase due to its fertilisation effect and also enhance the water use efficiency of the paddy. The temperature sensitivity experiments have shown that for a positive change in temperature up to 5°C, there is a continuous decline in the yield. For every one degree increment the decline in yield is about 6%. Also, in another experiment it is observed that the physiological effect of ambient CO₂ at 425 ppm concentration compensated for the yield losses due to increase in temperature up to 2°C. Rainfall sensitivity experiments have shown that increase in rice yield due to increase in rainfall above the observed values is near exponential. But decrease in rainfall results in yield loss at a constant rate of about 8% per 2 mm/day, up to about 16 mm/day.  相似文献   

Acoustic anisotropy related to anisotropic stress conditions during formation and unloading     

E. Fjaer  R. M. Holt  J. S. Rathore  B. Åhlén 《Geophysical Journal International》1991,107(3):687-691

  相似文献   

Snow and glacier melt runoff model to estimate hydropower potential     

Anil V Kulkarni  S S Randhawa  B P Rathore  I M Bahuguna  R K Sood 《Journal of the Indian Society of Remote Sensing》2002,30(4):221-228

Himalayan region has high concentrations of mountain glaciers. Large extent of this region is covered by seasonal snow during winter. Runoff generates from melting of these snow and glaciers is one of the important sources of water for the Himalayan Rivers. Glaciers and snowfields are distributed throughout the Himalayas and form a source of numerous streams. Due to steep slopes, all such streams have potential sites for hydropower generation. If this potential is fully utilized, it will help in generating power from environmentally friendly Run-of-River (RoR) hydropower stations. Considering these aspects, a stream flow simulation model was developed for small streams. This will help in estimation of average seasonal unrestricted hydropower potential of snow and glaciated streams for winter, summer, monsoon and autumn seasons. Information generated through remote sensing technique as glacier, permanent snow cover, seasonal snow cover, altitude of snow and glaciers were used in conjunction with daily maximum and minimum temperature, rainfall and discharge. The model was developed for Malana nala located in Parbati River basin near Kullu in Himachal Pradesh. It was validated at adjacent Tosh nala in the same basin. Seasonal runoff computed from the model is comparable with observed data for all seasons except Monsoon. Good results in autumn, winter and summer seasons demonstrates usefulness of runoff model to assess hydropower potential of snow and glaciated streams and therefore, the model was applied to ungauged Sorang Gad and Kirang Khad. In winter runoff was estimated as 1.8 and 1.69 cumecs for Kirang Khad and Sorang Gad, respectively. This is important, as viability of hydropower station depends upon winter stream runoff. These results suggest that the model is useful tool to assess initial estimate of hydropower potential for large number of snow and glaciated streams, for which no hydrological data is available.  相似文献