
Radiometric
Assay
This
facility exists not only at AMD Headquarter but also at all the
regional centers. The laboratory
extends support to the exploration programme by carrying out physical
assay of geological samples for uranium, thorium and potassium by
non-destructive radiometric techniques where gamma and beta emissions
from radioactive minerals are measured. Total gamma activity of the
samples is measured for their content. The uranium, thorium or
potassium content of rock samples are determined by measuring the
characteristic gammas of these elements using gamma-ray spectrometry.
The equipment is developed and fabricated in-house and consists of
NaI (Tl) crystal (solid or well type) with four single channel analysers
and other counting set up for multi-channel analysers with predefined
regions of interest. In case the samples are in disequilibrium
state due to weathering and various geological reasons, low energy
gamma-ray spectrometry is resorted to for determination of uranium
along with radium, thorium and potassium, enabling disequilibrium
studies.
The
laboratory also provides the facility for natural gamma-ray
logging of bore hole and core assay of the borehole core samples.
The concentration of eU3O8 is
determined in the range from ppm to percent level using either
GM detector or scintillation detector.
In
regions, these tasks are carried out by the Physics Laboratory
located in each region. The Regional Physics laboratories
also carry out repair and maintenance of instruments
available with them.
In addition, the laboratory at Hyderabad is also responsible
for the preparation and calibration of radiometric standards required
for borehole logging, shielded-probe logging, sample and core assay
work.

Neutron
Activation Analysis
Instrumental
neutron activation analysis (INAA) laboratory is located at AMD Headquarter,
Hyderabad. It is a nondestructive nuclear technique, employed to
find the elemental concentrations of Na, K, Ca, Sc, Cr, Fe, Co, Zn,
Ga,
As, Br, Rb, Ag, Sb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Tm, Ho,
Yb, Lu, Hf, Ta, W, Au, Th and U. Measurements from percentage
to ultra trace levels are possible by this technique. High purity
germanium co-axial/ planar solid-state detector coupled to PC-based
multichannel analyser is employed for spectrum analysis after irradiating
the sample in CIRUS reactor of BARC.

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