Methods for forming pathways of increased thermal conductivity for geothermal wells

A method of forming at least one pathway of increased thermal conductivity between a formation and a wellbore in a geothermal well comprising the steps:

• a) providing a conduit in the wellbore, the conduit having an internal passageway, at least one port between the internal passageway and an exterior of the conduit, and a sliding sleeve valve assembly for changing a configuration of the at least one port, wherein the at least one port is changeable between an open configuration, a closed configuration and an excluded configuration, wherein the excluded configuration restricts movement of material between the internal passageway and the exterior of the conduit;
• b) introducing a thermally conductive material into at least one fracture in the formation through the at least one port in the open configuration, wherein the thermally conductive material comprises a fluid and solid particles and in the excluded configuration of the at least one port, the solid particles of a predetermined size are prevented from moving between the internal passageway and the exterior of the conduit;
• and
• c) putting the at least one port in the excluded configuration and putting the well in an underbalanced state such that the pressure in the internal passageway is less than the pressure outside the conduit, causing the thermally conductive material to move towards the at least one port that is in the excluded configuration and for the solid particles to accumulate at the exterior of the conduit around the at least one port and the at least one fracture to form the at least one pathway of increased thermal conductivity between the formation and the conduit.