Standoff specific corrections for density logging

An apparatus for estimating a parameter of interest of a volume of an earth formation, the apparatus comprising:

• a conveyance device configured to be conveyed in a borehole intersecting the earth formation, the conveyance device comprising at least one nuclear sensor configured to make measurements of the volume relating to the parameter of interest;
• a caliper associated with the conveyance device and configured to determine a standoff of the at least one sensor relative to a wall of the borehole;
• a processor configured to:
• estimate a plurality of density measurements relating to the parameter of interest using radiation counts from the at least one nuclear sensor, with the at least one processor configured to associate each density measurement of the plurality of density measurements with one of a plurality of standoff bins corresponding to values for the standoff from the caliper while recording the counts associated with each density measurement in a non-transitory computer-readable storage medium accessible to the processor;
• determine a compensated density value for each standoff bin by correcting each density measurement of the plurality of density measurements using a correction model determined from a plurality of predefined models based on the standoff bin associated with the particular density measurement by using a standoff distribution profile to assign weights to the corrections due to standoff over a range of standoff values corresponding to the standoff bin;
• use the compensated density values for at least one standoff bin to determine a final compensated density value;
• and
• output the final compensated density value.