Granulometric Analysis: Radionuclide Activity, Uranium, Thorium & Potassium

[hariprasath]

why do we need to determine the particle size while estimating the activity of radionuclides?
is there any relation between the particle size (sand, silt and clay) and primordial radionuclide?
will the content of uranium, thorium and potassium rely on particle sizes?

 

[Astronuc]

why do we need to determine the particle size while estimating the activity of radionuclides?
is there any relation between the particle size (sand, silt and clay) and primordial radionuclide?
will the content of uranium, thorium and potassium rely on particle sizes?

Is one referring to ores? Particle size and composition are important with respect to shielding of alpha and beta activity, and alpha more so than beta. The composition, i.e., the proportion that is U or Th in the mineral is also important with respect to obtaining a correct assay. U and Th ores represent a variety of compositions with varying levels of U or Th compounds.

https://en.wikipedia.org/wiki/Uranium_ore

With respect to economics, one wishes to identify deposits that have the highest concentration of U or Th. This is also the motivation for any of the economically important elements, e.g., Au, Ag, REE, Pt, Rh, Co, Fe, Cr, Ni, Zr, . . . . .

 

[hariprasath]

thanks for the reply,
do there exists any relation between the minerals (Zn, Cu, Mn, Fe) that is found in the sediments with that of radionuclides (U, Th, K)?

 

[Astronuc]

thanks for the reply,
do there exists any relation between the minerals (Zn, Cu, Mn, Fe) that is found in the sediments with that of radionuclides (U, Th, K)?

There does not appear to be a specific or unique relationship, but rather, it is geologically or geographically dependent. For example, vanadium occurs in about 152 minerals, which could include various iron ores, but it is also a byproduct of certain uranium ores.

There is an example of uranium with Fe and Mn minerals, "The Ningyo-Toge uranium deposit is one of the typical sedimentary uranium deposits in Japan. In general, during weathering, U is removed from the basal granite through underground water. The underground water in this area is rich in U, and has a comparatively high concentration of Fe and Mn." http://www.sciencedirect.com/science/article/pii/0009254187901367

See page 275 in http://www.minsocam.org/msa/OpenAccess_publications/Craig_Vaughan/Craig_Vaughan_Chptr_10.pdf
The text discusses URANIUM-VANADIUM-COPPER ORES ASSOCIATED WITH SANDSTONES AND UNCONFORMITY-TYPE URANIUM DEPOSITS

One can also research Monazite and its distribution.

 

[hariprasath]

thank you for the answer sir, the link i went through is also useful in clarifying the doubts.