Fluid transport systems for use in a downhole explosive fracturing system

An explosive system comprising an assembly of two or more elongated casings for insertion into a borehole for use in fracturing a geologic formation surrounding the borehole, the explosive system including:

• a first elongated casing having a tubular body, first and second longitudinal end caps, and defining a first internal chamber;
• a second elongated casing having a tubular body, first and second longitudinal end caps, and defining a second internal chamber, the first and second casings being mechanically coupled together in axial alignment;
• each of the first and second casings comprising a first component of an explosive located within the respective internal chamber of the casing;
• and
• at least one inlet tube communicating with the first and second internal chambers of the respective first and second casings, the at least one inlet tube being operable to deliver a second component of the explosive into the first and second internal chambers so as to combine with the first component of the explosive to comprise the explosive.

A method comprising:

• inserting an explosive assembly into a wellbore, the assembly comprising a first explosive unit and a second explosive unit, each explosive unit having a casing with a first component of an explosive within the casing;
• and then
• flowing a second component of the explosive into the inserted casings of the first and second explosive units using a common inlet tube extending through each casing to comprise the explosive within each explosive unit;
• detonating the explosive to fracture the geologic structure surrounding the borehole and the casings.