Search

The upper Ordovician reservoir is one of the leading producing units in SW part of the Murzuq basin; it has a complex architecture inherited from the glacial effects on the braided fluvial deposits of the late stage at this era. The ultimate target for any petrophysical evaluation is to determine the quantities of water saturation and porosity accurately, but unfortunately, the models for thinly interbedded sand and shale layers are not straightforward. Therefore in this paper, an effort has been made to delineate and distinct between the types of interbedded (shaly -sand and sandyshale layers), and lithology end members by application compressional compliance versus density cross-plot in the two studied wells. After that, the determination of the thinly interbedded of layers type is augmented by correlating Vp-compliance with Poisson's ratio, effective porosity, and VP/VS. Among all the examined cross-plot; Poison's ratio, VP/VS and effective porosity with compressional compliance enhanced the upper and lower boundaries of the thinly interbedded sand and shale layers of the Ordovician succession in Murzuq basin. The "Mamuniyat" formation (main reservoir) with more clean sand content displays low compressional compliance, low-velocity ratio, and low Poisson's ratio. In contrary, the rich TOC shale (Hot shale) shows high compressional compliance, high-velocity ratio and high Poisson's ratio. While the disputed sandstone, siltstones and silty shales of late Ordovician "Bir Tlacsin" formation has slightly higher compressional compliance, velocity ratio, and Poisson's ratio than the underlying Mamuniyat formation, which enables drawing a clear contact between two gradually graded formations in the areas with no abrupt changes. The estimated petrophysical and elastic and properties are then used as an input for electrofacies prediction in both wells, by using unsupervised neural network classification. The predicted petrophysical facies clusters in both wells failed to differentiate between the various type of shales. However, the petro-elastic facies cluster reliably delineated the interbedded sandy- shale and shaly-sand thin layers without using gamma-ray logs. The results will help to avoid and to reduce the errors made during fluid substitution and rock physics models of shaly -sand formations. [ABSTRACT FROM AUTHOR]

Evaluations of fruit quality and nitrogen, potassium, and calcium concentration of apple (Malus domesticaBorkh. cvs. Gala and Golab) grown with five treatments of NO3−:NH4+ratios were made in pot culture. The concentrations of NO3−:NH4+ratios were 2.5:0.1, 6:1, 6:0.7, 6:0.5, 6:0.3 meq L−1. Fruit size, percent dry matter, total dissolved solids, total acidity, or juice pH was not affected by increased ammonium in the ratio. Firmness decreased as the proportion of NH4+increased. Gala and Golab differed in some of these parameters. Concentrations of N and K increased as NH4+increased, whereas Ca had no trend or decreased. Generally, the treatment of 2.5:0.1 produced fruits with lower N but higher K and Ca concentrations than the other treatments. This research showed that some parameters such as fruit weight, length, and diameter, juice pH, and dry matter were not affected significantly by NH4+concentration whereas composition was affected. [ABSTRACT FROM PUBLISHER]