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Natural Resources Research - Recognition of reservoir quality is an important objective in reservoir characterization process. By definition, the quality of a reservoir is described by its... 相似文献
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ABSTRACT The intracratonic basins of central Australia are distinguished by their large negative Bouguer gravity anomalies, despite the absence of any significant topography. Over the Neoproterozoic to Palaeozoic Officer Basin, the anomalies attain a peak negative amplitude in excess of 150 mGal, amongst the largest of continental anomalies observed on Earth. Using well data from the Officer and Amadeus basins and a data grid of sedimentary thicknesses from the eastern Officer Basin, we have assessed the evolution of these intracratonic basins. One-dimensional backstripping analysis reveals that Officer and Amadeus basin tectonic subsidence was not entirely synchronous. This implies that the basins evolved as discrete geological features once the Centralian Superbasin was dismembered into its constituent basins. Two- and three-dimensional backstripping and gravity modelling suggest that the eastern Officer Basin evolved from a broad continental sag into a region of intracratonic flexural subsidence from the latest Neoproterozoic, when flexure of the lithosphere deepened the northern basin. The results from gravity modelling improve when the crust is thickened beneath the northern margin of the basin and thinned at the southern margin, as has been suggested by recent deep seismic data. The crustal thickening beneath the basin's northern margin abuts the region of greatest topographic relief and is consistent with the observed structure at the edges of many orogenic belts. If the Officer Basin evolved as a foreland-type basin from the late Proterozoic and has retained those features to the present, then one implication is that in the absence of any significant topography, cratonic lithosphere must be able to support stresses over very long periods of geological time. 相似文献
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Bassem S. Nabawy 《Arabian Journal of Geosciences》2014,7(3):889-898
In the present study, 12 theoretical models have been introduced for studying the effect of the grain size and shape on the intergranular porosity, ?. From the first eight models, it is stated that the grain size has no effect on the intergranular porosity, but it is declared that the smaller the grain size means the smaller the interstitial pore spaces and therefore, the less the ability of the pore spaces to receive finer sediments, then the higher the porosity. On the other hand, studying the present models revealed that the total intergranular porosity decreases when increasing the grain elongation ‘E’ (the length of the grain/the diameter of the grain) as a shape anisotropy parameter. A new equation has been introduced relating the total pore volume to the grain shape/elongation. $$ \emptyset = 26.188\ {E^{-1 }} + 21.431 $$ The grain sorting of the present models has been studied by adding another group of grains of the critical grain size of occupation inside the pore spaces; the pore volume decreases by about 41.0 % of the total porosity. To check the applicability of the proposed equation, 46 samples of highly porous sandstone have been selected from different places in Egypt and studied petrographically, and their total pore volume have been measured using Digital Image Analysis (DIA) ‘? Im’ and helium injection technique ‘? He.’ Petrographically, the studied samples are quartz arenite and ferruginous quartz arenite. The pore types are mostly characterized mostly as (1) intergranular porosity and rarely as (2) intragranular porosity, (3) vuggy porosity, and (4) fracture porosity. The grain elongation ‘E’ for the present samples has been measured using the DIA technique; it varies from 1.34 to 1.73. Porosity ‘? He’ varies between 25.8 and 34.7 %, gas permeability ‘k’ varies from 0.14 to 6.92 μm2 (very good to excellent rank), and the mean pore diameter ‘D’ varies between 3.9 and 25.7 μm (macro to mega pores). The study stated the applicability of the present equation and introduced a number of equations that could be used to calculate porosity, permeability, and pore radius in terms of grain elongation. The applicability of the present study has some limitations due to (1) cementation, (2) microporosity, and (3) fracturing. The effect of cementation can be minimized by processing the grains and the surrounding cement statistically as a bulk ellipsoid unit, whereas the micropores/fractures can be measured by helium injection. 相似文献
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Alex Fore Ziad S. Haddad T. N. Krishnamurti Ernesto Rodgridez 《Pure and Applied Geophysics》2012,169(3):415-424
One of the current problems in the accurate estimation of over-ocean wind from scatterometry observations is the proper accounting
for precipitation. Specific cases such as hurricanes are particularly difficult, because precipitation in the eye wall and
rain bands can be quite heavy, and therefore, affect the scatterometer signatures so drastically that a category-4 hurricane
can appear, to the scatterometer, to have category-1 winds. We have developed an approach to infer and account for the signature
of the precipitation from non-simultaneous passive-microwave measurements of rain, with the help of geostationary IR measurements.
In this note, we describe the basic approach, and the results of applying it to the data taken by the Tropical Rainfall Measurement
Mission Microwave Imager measurements several hours before and after the QuikSCAT observation of Hurricane Rita in September
2005. We also describe how we are enhancing the approach with more realism in the assimilation of the IR information. 相似文献
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Regional flood frequency analysis (RFFA) is often used in hydrology to estimate flood quantiles when there is a limitation
of at-site recorded flood data. One of the commonly used RFFA methods is the index flood method, which is based on the assumptions
that a region satisfies criterion of simple scaling and it can be treated homogeneous. Another RFFA method is quantile regression
technique where prediction equations are developed for flood quantiles of interest as function of catchment characteristics.
In this paper, the scaling property of regional floods in New South Wales (NSW) State in Australia is investigated. The results
indicate that the annual maximum floods in NSW satisfy a simple scaling assumption. The application of a heterogeneity test,
however, reveals that NSW flood data set does not satisfy the criteria for a homogeneous region. Finally, a set of prediction
equations are developed for NSW using quantile regression technique; an independent test shows that these equations can provide
reasonably accurate design flood estimates with a median relative error of about 27%. 相似文献
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John Jansen Bassem Haddad Wayne Fassbender Patrick Jurcek 《Ground Water Monitoring & Remediation》1992,12(4):103-109
A frequency domain electromagnetic induction sounding survey (FDEM) was conducted on a landfill in northern Illinois to determine the depth of fill, locate areas of drum disposal, and locate areas of heavy metal sludge disposal. Sketchy information obtained from interviews of the site personnel identified specific exploration targets and areas of concern. The results of the geophysical survey verified much of the reported disposal history and identified areas suspected to contain hazardous waste.
Based on the results of the survey, the thickness of fill was estimated and two areas with highly conductive fill were located. These areas could represent leachate pockets or sludge disposal areas. An area in which the fill appears to be thicker than expected was identified. This area is thought to represent industrial sludge disposal in trenches excavated into the existing fill and underlying soils. An area with several linear in-phase, quadrature, and conductivity highs was detected. A subsequent magnetometer survey detected linear magnetic anomalies that are believed to be caused by parallel trenches filled with steel drums. This area is believed to be a previously unreported hazardous waste drum disposal cell excavated into the native soil.
As of this writing, the results of this survey have not been verified by traditional intrusive methods. When these investigations begin, we expect that information provided by the FDEM survey will reduce project costs by directing subsequent investigations, thereby reducing the number of borings and test pits required to characterize the site. While there is an unavoidable margin of error and uncertainty in remote sensing methods, the subsurface coverage provided by this geophysical survey could not have been reproduced by traditional methods without substantial expense. This paper presents the results of the survey and discusses application of the FDEM method on landfills. 相似文献
Based on the results of the survey, the thickness of fill was estimated and two areas with highly conductive fill were located. These areas could represent leachate pockets or sludge disposal areas. An area in which the fill appears to be thicker than expected was identified. This area is thought to represent industrial sludge disposal in trenches excavated into the existing fill and underlying soils. An area with several linear in-phase, quadrature, and conductivity highs was detected. A subsequent magnetometer survey detected linear magnetic anomalies that are believed to be caused by parallel trenches filled with steel drums. This area is believed to be a previously unreported hazardous waste drum disposal cell excavated into the native soil.
As of this writing, the results of this survey have not been verified by traditional intrusive methods. When these investigations begin, we expect that information provided by the FDEM survey will reduce project costs by directing subsequent investigations, thereby reducing the number of borings and test pits required to characterize the site. While there is an unavoidable margin of error and uncertainty in remote sensing methods, the subsurface coverage provided by this geophysical survey could not have been reproduced by traditional methods without substantial expense. This paper presents the results of the survey and discusses application of the FDEM method on landfills. 相似文献
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