Identifying fracture barriers for hydraulic fracturing

A non-transitory computer-readable medium storing one or more instructions executable by a computer system to perform operations for identifying fracture barriers in a well, the operations comprising:

• converting rebound hardness values of a rock specimen from the well to unconfined compressive strength (UCS) values, wherein each of the rebound hardness values corresponds to a respective coordinate of a measurement grid imposed on the rock specimen, wherein the coordinates of the measurement grid are depth and columns;
• for each column of the grid, plotting the UCS values versus depth;
• mapping, based on a maximum UCS value and a minimum UCS value, a relative strength contour plot for the rock specimen;
• mapping, based on a fixed strength range, an absolute strength contour plot for the rock specimen;
• and
• determining, based on the relative strength contour, the absolute strength contour, and mineralogy of the rock specimen, that the rock specimen is indicative of a fracture barrier in the well.

An apparatus for identifying fracture barriers in a well, comprising:

• one or more processors;
• and
• a non-transitory computer-readable storage medium coupled to the one or more processors and storing programming instructions for execution by the one or more processors, the programming instructions instructing the one or more processors to perform operations comprising:
• converting rebound hardness values of a rock specimen from the well to unconfined compressive strength (UCS) values, wherein each of the rebound hardness values corresponds to a respective coordinate of a measurement grid imposed on the rock specimen, wherein the coordinates of the measurement grid are depth and columns;
• for each column of the grid, plotting the UCS values versus depth;
• mapping, based on a maximum UCS value and a minimum UCS value, a relative strength contour plot for the rock specimen;
• mapping, based on a fixed strength range, an absolute strength contour plot for the rock specimen;
• and
• determining, based on the relative strength contour, the absolute strength contour, and mineralogy of the rock specimen, that the rock specimen is indicative of a fracture barrier in the well.