Geologic pore system characterization framework

One or more non-transitory computer-readable media storing instructions that, when executed by at least one processor of a computing system, cause the computing system to perform operations, the operations comprising:

• acquiring nuclear magnetic resonance (NMR) data and sonic data for a borehole in a subsurface geologic region using a tool string disposed in the borehole;
• determining, from the sonic data, pore shape information for a plurality of pore shape classes;
• determining, from the NMR data, pore size information for a plurality of pore size classes;
• computing a T2 logarithmic mean for each of at least two pore size classes based on the NMR data;
• computing pore geometry parameters comprising a semi-long axis, a semi-short axis, and a cross-section area index using the pore shape information and the T2 logarithmic means;
• jointly processing the pore shape information, the pore size information, and the pore geometry parameters to determine pore-system properties of the subsurface geologic region;
• computing permeability values with respect to depth along at least a portion of the borehole based on the pore-system properties;
• and
• controlling movement of the tool string in the borehole based at least in part on the computed permeability values.

A system, comprising:

• one or more processors;
• and
• at least one memory comprising at least one non-transitory computer-readable medium storing instructions that, when executed by at least one of the one or more processors, cause the system to perform operations, the operations comprising:
• acquiring nuclear magnetic resonance (NMR) data and sonic data for a borehole in a subsurface geologic region using a tool string disposed in the borehole;
• determining, from the sonic data, pore shape information for a plurality of pore shape classes;
• determining, from the NMR data, pore size information for a plurality of pore size classes;
• computing a T2 logarithmic mean for each of at least two pore size classes based on the NMR data;
• computing pore geometry parameters comprising a semi-long axis, a semi-short axis, and a cross-section area index using the pore shape information and the T2 logarithmic means;
• jointly processing the pore shape information, the pore size information, and the pore geometry parameters to determine pore-system properties of the subsurface geologic region;
• computing permeability values with respect to depth along at least a portion of the borehole based on the pore-system properties;
• and
• controlling movement of the tool string in the borehole based at least in part on the computed permeability values.