Injection withdrawal tracer tests to assess proppant placement

Abstract

Placement of proppant in subterranean formations during hydraulic fracturing is assessed. A method of one aspect includes introducing a hydraulic fracturing fluid including a proppant into a subterranean formation through a well. Samples of the hydraulic fracturing fluid are recovered through the well over a period of time. A concentration of at least one tracer in each of the samples is determined. The concentrations of the at least one tracer in the samples are analyzed to assess placement of the proppant in the subterranean formation. Other methods, apparatus, and systems are also disclosed.