Mineralogy and Prospecting of heavy minerals in alluvial sediments of Karkheh River Khouzestan, Iran

The Preset study is on alluvial sediments with variable origin of the Karhkeh river, in order to recognize their heavy minerals dominant pattern distributions. The distribution data analyzed by monovariable. Variance and covariance cofficient statistical analyses. 100 samples which are collected from recent and old traces river sediments are considered fof studies on 30 heavy minerals which are seperated by heavy liquid method (Bromoform). Although, the net volum of heavy minerals in the study area is negiigible but the variation and local concentration of minerals is so high and considerable. The highest measured volume of heavy minerals after concentration of 5000c.cis still negligible. 5 samples were analyzed using XRD method to recognize other minerals and also confirme microscopic mineralogy observations. Also 7 samples were analyzed by NAA method to present correlation patterns of elements in high potential area. According to variance analyses and mineralogical studies most of the heavy minerals in the Karkheh sediments originate from 3 lithological units which are dominantly located in the upper parts of the basin and the Sanandaj- Sirjan Zone. Due to observation of bright and dark heavy minerals, total percent of bright heavy minerals (zircon – rutill – garnet and turmaline) in the Karkheh sediments is more than 5% (63285. 86 gr/t) and total percent of dark heavy minerals (ilmenite – hematite – chromite – ch romite – mangnetite) is more than 6% (7474.84 gr/t). Based on the procedure suggested by Rose & webb (1979) several high potential area pionts were selected for garnet, zircon, ilmenite and rutile explorations. Covariance coefficient shows close positive carrelation for zircon and rutile mineral in all samples and anomaly areas have similar quantites of these minerals. The quantity of ilmenite in all samples is consider ably high and several remarkable anomalous points are present. Garnet present with magnetite which is the most abundant mineral in alluvium, and shows a constant distribution along the field sampling.