Abstract
Origin and distribution of the heavy minerals of surficial and subsurficial sediments has been investigated in the alluvial Nile River terraces, Khartoum North, Sudan. Heavy mineral assemblages in the very fine sand fraction (0.063 - 0.125 mm) of 10 sediment samples were identified using petrography microscope. Results of descriptive statistical parameters revealed that most sediments samples belonged within very poorly sorted to extremely poorly sorted, strongly negative skewed to strongly positive skewed and mesokurtic to very leptokurtic. The quartz was the dominant in the opaque minerals in all sediments. The non-opaque heavy minerals were dominant by zircon, tourmaline, rutile, garnet, sillimanite, and andalusite. Results revealed that the ultrastable minerals (zircon, tourmaline and rutile) were found in all sediments with range from (2% - 47.36%, 2.08% - 29% and 3% - 24.99%), respectively. Garnet, sillimanite and andalusite were also found with range from (5% - 67%, 1% - 9.09% and 1% - 50%), respectively. Heavy mineral assemblage indentifies sources that are not bounded to the local origin. The proportion and presence of heavy minerals from outside source rocks indicated relatively strong reworking of zircon sand from the outer-shelf to inner-shelf as well relatively long distance of transport. Fluvial and Aeolian sediments were the dominant environments in the investigated area. We conclude that most heavy minerals in the study area are originally derived from gneisses and schist metamorphic rocks and some igneous rocks of the Ethiopian plateau.
Highlights
Heavy minerals are defined as high density minerals, which have specific gravities of 2.9 g∙cm−3 or higher [1]
Laboratory errors caused by heavy mineral separation during sample preparation could influence the heavy mineral assemblages
The aim of this study was to identify the non-opaque heavy minerals assemblage of the surficial and subsurficial sediments in the Nile terraces at Khartoum North, Sudan in an attempt to refer them to their origin
Summary
Heavy minerals are defined as high density minerals, which have specific gravities of 2.9 g∙cm−3 or higher [1]. The heavy mineral assemblage in sediments usually reflects their parent rocks as well their origin. Over the last two decades, specific heavy minerals including zircon, monazite, garnet, tourmaline, apatite, rutile, and Ti-Fe oxide minerals have been widely used to decipher the provenances of marine and Nile river sediments in terms of their unique varietal characteristics [4]. According to [5] the factors which influence the assemblage of the heavy minerals include weathering at different stages between the original source rocks and sedimentary environments, mechanical abrasion during transportation, physical sorting and diagenetic processes during buried. Laboratory errors caused by heavy mineral separation during sample preparation could influence the heavy mineral assemblages
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
