Systems and Methods for Identifying Sanding in Production Wells Using Time-Lapse Sonic Data

A system for identifying a layer of a formation through which a borehole extends that exhibits a significant increase in a volume of sand that reduces a volume of hydrocarbon production during the course of production at the borehole, comprising:

• an acoustic tool including an acoustic source configured to generate an acoustic wave and an array of acoustic receivers configured to receive data corresponding to the acoustic wave, the acoustic tool being located in the borehole;
• and
• a control unit comprising at least one processor and a memory, wherein the control unit is configured to:
• cause the acoustic source to generate a first acoustic wave at a first time;
• receive first data from the array of acoustic receivers, the first data corresponding to the first acoustic wave;
• obtain Stoneley dispersion data and cross-dipole flexural dispersion data from the first data;
• determine a horizontal shear modulus, C66, using the Stoneley dispersion data obtained from the first data;
• determine at least one vertical shear modulus, C44 or C55, using the cross-dipole flexural dispersion data obtained from the first data;
• cause the acoustic source to generate a second acoustic wave at a second time, the second time being subsequent to the first time;
• receive second data from the array of acoustic receivers, the second data corresponding to the second acoustic wave;
• obtain Stoneley dispersion data and cross-dipole flexural dispersion data from the second data;
• determine a horizontal shear modulus, C66, using the Stoneley dispersion data obtained from the second data;
• determine at least one vertical shear modulus, C44 or C55, using the cross-dipole flexural dispersion data obtained from the second data;
• and
• analyze changes in the horizontal and vertical shear moduli determined from the first and second data, wherein the changes provide an indication of a change in anisotropic characteristics of the layer of the formation resulting from production at the borehole.