<> "The repository administrator has not yet configured an RDF license."^^ . <> . . . "Source Parameters of Injection-induced Microseismicity"^^ . "We analyze source parameters of microseismic events (M < − 1) associated with high flow-rate water injections in a shale formation at a depth of 220 m. Two types of events were observed several hundred impulsive events with clear P- and S-wave arrivals, and continuous emissions with peaked spectra detected well into the experiment. For a representative collection of impulsive events, an −2 model provided satisfactory fits to displacement spectra corrected for attenuation, and average quality factors of 34 and 15 were obtained for P and S waves. P-wave first motion analysis and E S  /E P ratios indicated the existence of a non-double-couple component in some events, particularly early in the experiment. A clear difference was observed for estimates of stress release parameters as non-double-couple events had smaller stress drops and apparent stresses. The seismic efficiency of double-couple and non-double-couple events was limited to 0.9% and 0.05% respectively, with average values being 0.25% and 0.02%. A comparison of our results with those reported for a similar magnitude range in a hard-rock formation indicates considerably smaller estimates of stress drop and apparent stress in our case while seismic efficiencies are comparable."^^ . "1998-11" . . "153" . "1" . . "Springer Verlag"^^ . . . "Pure and Applied Geophysics"^^ . . . "00334553" . . . . . . . . . . "Tom J."^^ . "Boone"^^ . "Tom J. Boone"^^ . . "Shahrair"^^ . "Talebi"^^ . "Shahrair Talebi"^^ . . "CANMET, Canada"^^ . . . "Imperial Oil Resources Ltd., Canada"^^ . . . . . . "HTML Summary of #1510 \n\nSource Parameters of Injection-induced Microseismicity\n\n" . "text/html" . . . "Source parameter estimation" . . . "Alberta" . . . "Unconventional hydrocarbon extraction" . .