Document Details

Document Type : Article In Journal 
Document Title :
Radiogenic Isotope Fractionation as an Indication for Uranium Mobility in the Granites of El Shallal Area, West Central Sinai, Egypt
تجزؤ نظائر سلسلة اليورانيوم كدليل على حركة اليورانيوم فى جرانيتات منطقة الشلال، غرب وسط سيناء، مصر
 
Subject : Earth Sciences 
Document Language : English 
Abstract : The granitic rocks at Wadi El Shallal area are categorized into metaluminous hornblende-biotite granites and peraluminous two-mica granites. The chemical analyses indicate that the two-mica granites are slightly altered and characterized by high uranium and thorium contents (averages 20.27 and 27.12 ppm, respectively). Compared to the hornblende-biotite granites, the 230Th/234U and 234U/238U activity ratios of the two-mica granites display values that depart significantly from equilibrium. The sample plots of the two granitic types are distributed in a trend reflecting more 234U loss from the two-mica granites. Leaching experiments confirmed that the area around mineral grain boundaries are more enriched in 234U relative to its parent 238U as a result of ?-recoil process that displaces the daughter nuclei outside the grain surface. This daughter (234U) is ejected from the grain into the open spaces and therefore, subjected to leaching by fluids. The observed uranium series disequilibrium in the granitic rocks from El Shallal area reflects isotopic fractionation and a recent migration of uranium in the two-mica granites. The high uranium contents and U-Th isotopic composition of the two-mica granites fairly suggest that these rocks are probably the source for uranyl mineralization of the nearby Um Bogma Formation reflecting a history of leaching, mobilization and precipitation by meteoric and groundwater. However, more intensive investigations for uranium series disequilibrium of local groundwater and uranyl mineralization of Um Bogma Formation are recommended. 
ISSN : 1012-8832 
Journal Name : Earth Sciences Journal 
Volume : 20 
Issue Number : 1 
Publishing Year : 1430 AH
2009 AD 
Number Of Pages : 23 
Article Type : Article 
Added Date : Sunday, October 11, 2009 

Researchers

Researcher Name (Arabic)Researcher Name (English)Researcher TypeDr GradeEmail
يحيى حسن داودYehia H. DawoodResearcher  

Files

File NameTypeDescription
 21610.pdf pdf 

Back To Researches Page