[en] Gamma-radiation data obtained on Madras beach has been analysed and it is found that there is a good negative correlation between the grain size and the observed gamma ray activity. A method has been proposed to utilize this correlation to obtain average grain size by much easier procedure, in comparison to sieve analysis, using the gamma-radiation intensity. This procedure can be used where the beach sand is not having anomalously high radiations (which are caused by monazite and other minerals). A case study from marina beach area, Madras is presented and it is suggested that this method can be applied to other areas by developing correlation relationships for the area under investigation. (author). 4 refs., 2 figs

[en] Promising uraniferous area in parts of Central India was brought out by integration of multi sensor and multi platform data sets. The study of multiple aerospace data sets available on analog and digital format and their integration using visual and digital processing techniques have helped in delineating the lithocontacts and different structural elements and their relation with uranium mineralization. The lithological discrimination and identification of contacts between various lithounits were achieved using airborne gamma-ray spectrometric survey (AGRS) data, as well as, spectral signatures of the rocks. The digital data analyses using linear contrast and histogram equalization, appeared useful in demarcating anomalous color patches, extension of shear zone (ENE-WSW), also parallel fractures ENE-WSW, and cross faults NW-SE influencing uranium mineralization in granitised granites and migmatites. The statistical analyses of AGRS data in combination with ground radiometric data indicate non-magmatic nature of uranium in the area. (author). 8 refs., 3 figs., 4 ills., 3 tabs

[en] Total intensity magnetic data of Umra area are subjected to low- and high- pass filtering. The filtered maps bring out the nature of deep seated as well as shallower features and several faults. Apparent resistivity and chargeability contour maps of the area are correlated with the filtered maps and bore hole data. The successful bore holes drilled in the area occur at the intersection of the inferred faults, suggesting a method of choosing areas for detailed investigations from magnetic anomaly maps. (author). 17 refs., 6 figs

[en] Regional emanometric survey using the closed circuit technique was carried our for measurement of radon and thoron concentration in the soil covered areas of Mogarra and Bijepar, Bhandara district, Maharashtra. The aim of the survey was to delineate potential areas for subsurface uranium bearing horizons to be taken up for detailed investigations. The radon and thoron values obtained from the survey were correlated with the soil samples analysis data by the method of class intervals and cumulative frequency analysis. Anomalous zones holding promise for subsurface uranium occurrences have been identified, substantiated by statistical treatment and recommended for detailed investigations (author). 11 refs., 5 figs