Seismic monitoring below source tool

A sensory assembly and system can be used in a wellbore to detect and characterize the earth strata and formations around the wellbore, where a signal emitting sensory tool is part of a tool string deployed in the wellbore, and where weighted fiber optic cable is deployed in an extended position below the signal emitting sensory tool. The fiber optic cable is also part of wire-line, slickline, or coiled tubing injector head connected to the signal emitting sensory tool, thereby providing fiber optic cable both above and below the signal emitting sensory tool in position to collect backscatter signals from earth strata and formations around the wellbore. The collection of backscatter signals, particularly from below the signal emitting sensory tool, allows for more precise characterization of formations and fractures within the earth strata.