Annals Geol. Surv. Egypt, V. XXIV (2001), PP. 507-520

APPLICATION OF GAMMA LOGGING TO STUDY

URANIUM CONTENTS WITHIN ABU – TARTUR

GRAVELLITIC PHOSPHORITE, KHARGA OASIS

NEW VALLEY, EGYPT

El Hakim, B., Saber, H. S., Abd Allah, A. A. and Kamel, A. M.

Egyptian Geological Survey And Mining Authority

ABSTRACT

Natural radioactivity logging was used inside 100 exploratory phosphorite boreholes at Abu – Tartur area, New Valley, having total depth of about 16 Km, and the average depth of boreholes was about    160 m. The studied area was about 23 Km2.

Isorad, isopach and structural contour maps were constructed for two main gravellitic phosphorite beds ( out of four beds ). Equivalent uranium was estimated within each bed, iso – equivalent uranium content contour map was constructed , and the approximate amount of uranium was calculated.

Depths of boreholes range from 118 to 197 m, while depth to the 1st gravellitic bed varies from 90 – 156m, and depth to the 2nd bed varies from 94 to 161m. Thickness of 1st bed ranges from 0.15 to 0.8m , and that for the 2nd from 0.10 to 0.95m.

Equivalent uranium in parts per million varies from 16 to 131 ppm (two to three times higher than that of the main economic phosphorite bed).

Approximate amount of equivalent uranium within the 1st bed was estimated to be equal to about 927 ton and within the 2nd bed about 685 ton, so the total amount of estimated equivalent uranium within the two beds equals about 1612 ton.