Tagged propping agents and related methods

1. A method for tracking the backflow of proppants in a fractured subterranean formation into which a plurality of proppant composition particles comprising a non-radioactive, detectable tracer uniformly distributed in a ceramic composition have been introduced, comprising analyzing a sample of the backflow by detecting for presence of the tracer in the sample.

2. A method as set forth in claim 1 wherein the subterranean formation has a plurality of zones and the backflow is tracked by introducing a plurality of types of said proppant composition particles, wherein each type of proppant composition particles is tagged with a tracer distinguishable from tracers of the other types of proppant composition particles, directing each of the types of proppant composition particles to a different zone, analyzing a sample of the flowback from at least one of the zones by detecting for presence of each of the tracers, and thereby identifying the type of proppant composition particles associated with the flowback.

3. A method as set forth in claim 2 wherein at least one of the tracers is a combination of types of tracers.

4. A method as set forth in claim 1 wherein the presence of the tracer is detected by X-ray fluorescence, inductively-coupled plasma, or proton-induced X-ray emission.

5. A method as set forth in claim 1 wherein the non-radioactive, detectable tracer is selected from the group consisting of lanthanides, strontium, barium, gallium, germanium, tantalum, zirconium, vanadium, chromium, manganese and combinations thereof.

6. A method as set forth in claim 1 wherein the non-radioactive, detectable tracer is selected from the group consisting of lanthanum, cerium, strontium, barium, gallium, germanium, and combinations thereof.

7. A method as set forth in claim 1 wherein the non-radioactive, detectable tracer is selected from the group consisting of lanthanum, cerium, and combinations thereof.

8. A method as set forth in claim 1 wherein the proppant composition particles are substantially free of resin.

9. A method as set forth in claim 1 wherein the proppant composition particles consist essentially of the non-radioactive, detectable tracer uniformly distributed in a ceramic composition.

10. A method as set forth in claim 1 wherein the non-radioactive, detectable tracer is in contact with the ceramic composition.

11. A method as set forth in claim 1 wherein the proppant composition particles are at least partially coated with a coating material.

12. A method as set forth in claim 11 wherein the coating material is resin.

13. A method as set forth in claim 1 wherein the proppant composition particles are of a size that is selected from the group consisting of (a) from about 20 mesh to about 40 mesh, (b) from about 16 mesh to about 20 mesh, (c) from about 30 mesh to about 50 mesh, (d) from about 30 mesh to about 60 mesh, and (e) from about 16 mesh to about 30 mesh.

14. A method as set forth in claim 1 wherein the tracer makes up about 0.03 to about 0.2 percent by weight of the composition of the proppant composition particles.

15. A method as set forth in claim 1 wherein the non-radioactive, detectable tracer is not present in the ceramic composition or is present in the ceramic composition in a concentration that is less than about 1,000 ppm based on weight.

16. A method for tracking the backflow of proppants in a fractured subterranean formation into which a plurality of proppant composition particles comprising a non-radioactive, detectable tracer uniformly distributed in a ceramic composition have been introduced, comprising analyzing a sample of the backflow by detecting for presence of the tracer in the sample; wherein:

(a) the non-radioactive, detectable tracer is selected from the group consisting of lanthanides, strontium, barium, gallium, germanium, tantalum, zirconium, vanadium, chromium, manganese and combinations thereof;

(b) the proppant composition particles are of a size that is selected from the group consisting of (i) from about 20 mesh to about 40 mesh, (ii) from about 16 mesh to about 20 mesh, (iii) from about 30 mesh to about 50 mesh, (iv) from about 30 mesh to about 60 mesh, and (v) from about 16 mesh to about 30 mesh; and

(c) the tracer makes up about 0.03 to about 0.2 percent by weight of the composition of the proppant composition particles.

17. A method as set forth in claim 16 wherein the proppant composition particles consist essentially of the non-radioactive, detectable tracer at least partially embedded uniformly distributed in a ceramic composition.

18. A method as set forth in claim 17 wherein the non-radioactive, detectable tracer is not present in the ceramic composition or is present in the ceramic composition in a concentration that is less than about 1,000 ppm based on weight.

19. A method as set forth in claim 18 wherein the non-radioactive, detectable tracer is selected from the group consisting of lanthanum, cerium, strontium, barium, gallium, germanium, and combinations thereof.

20. A method as set forth in claim 19 wherein the non-radioactive, detectable tracer is selected from the group consisting of lanthanum, cerium, and combinations thereof.

21. A method as set forth in claim 16 wherein the subterranean formation has a plurality of zones and the backflow is tracked by introducing a plurality of types of said proppant composition particles, wherein each type of proppant composition particles is tagged with a tracer distinguishable from tracers of the other types of proppant composition particles, directing each of the types of proppant composition particles to a different zone, analyzing a sample of the flowback from at least one of the zones by detecting for presence of each of the tracers, and thereby identifying the type of proppant composition particles associated with the flowback.

22. A method as set forth in claim 21 wherein at least one of the tracers is a combination of types of tracers.