Common field tests used initially to inform and eventually to truth fracture propagation models include
observing well logs, seismic testing, sonic logs, gamma ray logs, resistivity logs, and monitoring fluid injection
and downhole pressures of the well during hydraulic fracturing, among other techniques.11 Seismic testing is
a technique that can be run on the surface of the Earth, but most techniques require an observational well
to be drilled for monitoring purposes. A few field techniques will be discussed below