Lower carboniferous coal deposition environments on Spitsbergen, Svalbard     

W.H. Abdullah  D. Murchison  J.M. Jones  N. Telnaes  J. Gjelberg 《Organic Geochemistry》1988,13(4-6)

Two coal-bearing units from the Lower Carboniferous succession in Central Spitsbergen, Svalbard, have been investigated using coal petrographic and geochemical techniques. The upper member consists mainly of algal cannels, dominated by Botryococcus-type algae. The coals from the lower member are a mixture of durite-type coals with sporinite and inertinite and coals containing prdominantly vitrinite. The Rock-Eval and pyrolysis-GC also show a clear distinction in the composition of the organic matter in the two coal-bearing units investigated. These results, together with detailed sedimentological analyses, are used to reconstruct the depositional environments for the two coal-bearing sequences.  相似文献   

Analyzing spatial disparities in access to health care: A methodology with application in Bangladesh     

Abdullah A. Khan Ph. D. 《GeoJournal》1985,10(1):91-107

This paper develops a methodology for analyzing spatial disparities in access to health care in situations where the data base is limited, and applies it in the context of Bangladesh. The proposed indirect measures of inpatient and outpatient service utilization, and of quality of available services, seem to provide reasonably accurate, consistent, and interpretable results; these indices are combined into a composite index of relative access to health care. The form of the composite index and its components permits the incorporation of Sopher's disparity index into the methodology for measuring urban-rural disparities in relative access to health care. The empirical analysis based on subdivision level data revealed that Bangladesh's health care delivery system is, in general, characterized by extremely low level of access and a high degree of disparity in favor of urban areas, especially in terms of inpatient services. Spatial patterns of relative access and urban/rural disparity were perused through cartographic and statistical analyses; although clear-cut regional patterns did not emerge, the considerable spatial variations could be explained largely with reference to urbanization and density of population. Assuming improved level of access and minimal urban/rural disparity as basic policy goals a method to prioritize spatial units for future allocation of health sector resources is recommended.The author gratefully acknowledges the helpful comments on an earlier draft of this paper by Dr. S. M. Bhardwaj, Professor of Geography, Kent State University.  相似文献   

Application of a two-dimensional electrical tomography technique for investigating landslides along the Amman–Dead Sea highway, Jordan     

Awni T. Batayneh  Abdullah A. Al-Diabat 《Environmental Geology》2002,42(4):399-403

Electrical tomography geophysical surveys were conducted with the SYSCAL-R2 resistivity instrument at the location of instantaneous rock failure of a few 1,000s m³ along the Amman-Dead Sea highway, Jordan, providing a ground image for investigating landslide sites which caused material damage and closed the road. This slide occurred along two major fault planes after heavy rainfall in a rock consisting of a succession of shale, marl and marly limestone layers which were folded, tilted and fractured. Three electrical tomography profiles were performed along the axis of the slope to assess the landslide risk in such potential unstable areas. The results obtained, based on two-dimensional inversion of field data, have allowed mapping of the shale zones at depths which are characterized by a lower resistivity value, and have demonstrated that the rupture was initiated at the contact between the shale mass (black colored) and the massive limestone (white, yellowish-brown colored).  相似文献   

Area Influence Kriging     

Arik  Abdullah 《Mathematical Geosciences》2002,34(7):783-796

This paper presents a modified ordinary kriging technique referred to as the “Area Influence Kriging” (AIK). The method is a simple and practical tool to use for more accurate prediction of global recoverable ore resources in any type of deposit. AIK performs well even in deposits with skewed grade distributions when the ordinary kriging (OK) results are unreasonably smooth. It is robust and globally unbiased like OK. The AIK method is not intended to replace OK, which is a better estimator of the average grade of the blocks. Rather it aims to complement OK with its excellent performance in predicting recoverable resources that have been the major pitfalls of OK in many resource estimation cases. The paper details the methodology of AIK with a couple of examples. It also reports the results from its application to a gold deposit.  相似文献   

Quantifying threats to groundwater resources in the Republic of Maldives Part I: Future rainfall patterns and sea‐level rise          下载免费PDF全文

Abdullah A. Alsumaiei  Ryan T. Bailey 《水文研究》2018,32(9):1137-1153

Reserves of fresh groundwater on atoll islands are extremely fragile due to climatic and anthropogenic stresses. Of major concern is the quantity of water to be available in the coming decades under the influence of variable rainfall patterns, rising sea level, environmental conditions, and expected population growth that depends on groundwater resources. In this study, a 3‐dimensional numerical modelling approach using the SEAWAT modelling code is used to estimate freshwater lens volume fluctuation for 4 representative islands in the Republic of Maldives in response to long‐term changes in rainfall, sea‐level rise (SLR), and anthropogenic stresses such as groundwater pumping and short‐term impacts from tsunami‐induced marine overwash events. This work is divided into 2 papers. This first paper presents numerical model set‐up and calibration, and the effect of future rainfall patterns and SLR on fresh groundwater reserves. The second paper focuses on marine overwash events. The results of simulated future freshwater lens volume presented in the first study contribute to efficient groundwater resources planning and management for the Maldives in the upcoming decades. Freshwater lenses in small atoll islands (area < 0.6 km²) are shown to have a strong variability trends in the upcoming decades with expected reduction in lens volume between 11% and 36% due to SLR. In contrast, freshwater lenses in larger atoll islands (area > 1.0 km²) are shown to have less variability to changing patterns with expected reduction in lens volume between 8% and 26% due to SLR. Study results can provide water resource managers with valuable findings for consideration in water security measures.  相似文献   

Particulate matter dispersion and haze occurrence potential studies at a local palm oil mill     

L. C. Abdullah Ph.D.  L. L. Wong M.Sc.  M. Saari Ph.D.  A. Salmiaton Ph.D.  M. S. Abdul Rashid Ph.D. 《International Journal of Environmental Science and Technology》2007,4(2):271-278

The emissions from palm oil industry through incineration and open burning are the major sources of air pollutions contribution in Malaysia. The consequence of increasing the particulate concentration, the particulate matter dissolves with vapour and grows into droplets when the humidity exceeds approximately 70% and causing opaque situation known as haze. This work focuses on the dispersion particulate matter from palm oil mill. Gaussian Plume Model from a point source, subject to various atmospheric conditions is used to calculate particulate matter concentration then display the distribution of plume dispersion using geographic information system. Atmospheric Stability, mixing height, wind direction, wind speed, natural and artificial features play an important role in dispersion process. Study on the dispersion of particulate matters and the haze potential are presented as a case study in this paper. The data obtained will be served as the purpose of modeling the transport of particulate matter for obtaining permits and prevention of significant deterioration to the environment.  相似文献   

Letter to the editor     

Hafzullah Aksoy  N. Erdem Unal  Abdullah Gedikli 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(4):447-449

  相似文献   

Performance of a steel structure on Ar-Rayyas Sabkha soils     

Abdullah?A.?SabtanEmail author 《Geotechnical and Geological Engineering》2005,23(2):157-174

Sabkha deposits cover extensive areas along the Red Sea and the Arabian Gulf shores. They are the site of huge industrial complexes in spite of their low bearing capacity of its upper part. The strength of the Sabkha soil is controlled by several factors, among them are the evaporatic salts that cement the grains. The Standard Penetration Test (SPT) is used extensively in this terrain but its results are misleading. The Sabkha soil that may give high N value will lose most of its strength upon wetting as part of the salts are dissolved. Therefore, the design N value was adjusted for Sabkhas to account for salt migration, by relating the SPT (N) value to the Sabkha moisture and salt content. A steel structure factory that was placed in an eastern Saudi Arabian virgin Sabkha deposits was considered. After a few years of operation fresh water leaked through the ground and caused signi.cant differential collapse settlement which threatened the functional integrity of the superstructure. The differential settlement was con.ned to one area of the structure indicating that localized conditions must have contributed to the observed settlement. The subsurface conditions and the geotechnical properties of the site are presented. A statistical model was developed that quanti.es the effect of the moisture and salt content on SPT (N) values. A simple site procedure is suggested to correct the design N value in similar cases. It was found that the increase in the moisture content could reduce the SPT (N) values by as much as 60, good agreements were found between the measured and predicted N values.  相似文献   

The Logar ultrabasite massif and its reflection in the magnetic field (East Afghanistan)     

Abdullah Shareq  V.N. Voinov  E.B. Nevretdinov  L.V. Kubatkin  I.A. Gusav 《Tectonophysics》1980,62(1-2)

The paper deals with the structural position of the Logar ultrabasite massif with respect to the folded Kabul block. The ultrabasite is composed of a thick tectonic mantle in the ophiolite belt in the northern portion of south eastern Afghanistan. Magnetometric data together with geological investigations make it possible to understand the tectonic nature of the massif contacts.  相似文献   

Estimation of Longshore Sediment Transport Rate for a Typical Pocket Beach Along West Coast of India     

V. Noujas  R. S Kankara  K. Rasheed 《Marine Geodesy》2018,41(2):201-216

Estimation of Longshore Sediment Transport Rate (LSTR) in the littoral zone is essential for managing and developing any coastal zone. Numerical models are powerful tool to understand and investigate various processes responsible for LSTR in a systematic manner since direct measurement of LSTR is a difficult task. A one dimensional LITDRIFT model was implemented along the Vengurla coast for estimation of LSTR and to analyze the sensitivity of each input parameters towards the computation of LSTR. Major input parameters required for the estimation of LSTR are nearshore wave climate, bathymetry, and sediment characteristics. The nearshore wave data at a depth of 15 m were collected using wave rider buoy in 2015 is used in the present study. Field observations were carried out to survey the regional bathymetry and sediment characteristics. Annual net LSTR along Vengurala coast is relatively less and varies from ?7778 to ?9015 m³ with an average of ?8511 m³. The net direction of LSTR is towards south and gross LSTR is 1.18 × 10⁵ m³/year. The LSTR reveals more sensitivity to coastline orientation and wave direction. A 1° changes in coastline angle and wave direction causes approximately 3000 m³/month difference in LSTR. Moreover, wave height, wave period, and bed roughness has an important role for controlling LSTR. The model results help to identify the role of each parameter contributing towards LSTR estimation and a similar model approach can be applied to other coasts for estimating LSTR in an accurate way.  相似文献