Methods of detecting the locations of well treating fluids

A method of detecting the subterranean location of a well treating fluid after the treating fluid has been introduced into a well and used for performing a treatment therein comprising the steps of:

• (a) combining a nonhazardous thermal neutron absorbing material with said treating fluid, wherein said thermal neutron absorbing material is insoluble in water;
• (b) introducing said treating fluid including said thermal neutron absorbing material into said well and performing a well treatment in said well therewith;
• (c) emitting fast neutrons from a source thereof in said well whereby said fast neutrons interact with elements in said well and are thermalized thereby;
• (d) detecting thermal neutrons backscattered in said well and generating a count representative of the detected thermal neutrons over one or more selected subterranean intervals in said well;
• and
• (e) determining the subterranean locations of said treating fluid in said well in response to the differences in said count generated in step (d) and a count representative of said one or more subterranean intervals in said well before the well treatment of step (b) is performed due to thermal neutrons being absorbed by said thermal neutron absorbing material in said treating fluid.

A method of detecting the subterranean location of an aqueous hydraulic cement composition after the cement composition has been introduced into a zone to be cemented in a well comprising the steps of:

• (a) combining a nonhazardous thermal neutron absorbing material with said cement composition, wherein said thermal neutron absorbing material is insoluble in water;
• (b) introducing said cement composition including said thermal neutron absorbing material into said zone to be cemented;
• (c) emitting fast neutrons from a source thereof in said well whereby said fast neutrons interact with elements in said well and are thermalized thereby;
• (d) detecting thermal neutrons backscattered in said well and generating a count representative of the detected thermal neutrons over one or more selected subterranean intervals in said well;
• and
• (e) determining the subterranean locations of said cement composition in said well in response to the differences in said counts generated in step (d) and a count representative of said one or more subterranean intervals in said well before said cement composition is introduced therein in accordance with step (b) due to thermal neutrons being absorbed by said thermal neutron absorbing material in said cement composition.

A method of detecting the subterranean location of a well treating fluid after the treating fluid has been introduced into a well and used for performing a treatment therein comprising the steps of:

• (a) prior to introducing said treating fluid into said well, emitting fast neutrons from a source thereof in said well whereby said fast neutrons interact with elements in said well and are thermalized thereby;
• (b) detecting thermal neutrons backscattered in said well and generating a count representative of the detected thermal neutrons over one or more selected subterranean intervals in said well;
• (c) combining a nonhazardous thermal neutron absorbing material with said treating fluid, wherein said thermal neutron absorbing material is insoluble in water;
• (d) introducing said treating fluid including said thermal neutron absorbing material into said well and performing a well treatment in said well therewith;
• (e) again emitting fast neutrons from a source thereof in said well whereby said fast neutrons interact with elements in said well and are thermalized thereby;
• (f) again detecting thermal neutrons backscattered in said well and generating a count representative of the detected thermal neutrons over said one or more selected subterranean intervals in said well;
• and
• (g) determining the subterranean locations of said treating fluid in said well in response to the differences in said counts generated in steps (b) and (f) due to thermal neutrons being absorbed by said thermal neutron absorbing material in said treating fluid.