Gardner's relation
Gardner's relation,orGardner's equation,named after G. H. F. Gardner and L. W. Gardner, is an empirically derived equation that relatesseismicP-wavevelocity to thebulk densityof thelithologyin which the wave travels. The equation reads:
whereis bulk density given in g/cm3,is P-wave velocity given in ft/s, andandare empirically derived constants that depend on thegeology.Gardner et al. proposed that one can obtain a good fit by takingand.[1]Assuming this, the equation is reduced to:
where the unit ofis feet/s.
Ifis measured in m/s,and the equation is:
This equation is very popular inpetroleum explorationbecause it can provide information about the lithology from interval velocities obtained from seismic data. The constantsandare usually calibrated fromsonicanddensitywell log information but in the absence of these, Gardner's constants are a good approximation.
References
[edit]- ^Gardner, G.H.F.; Gardner L.W.; Gregory A.R. (1974)."Formation velocity and density -- the diagnostic basics for stratigraphic traps"(PDF).Geophysics.39:770–780.Bibcode:1974Geop...39..770G.doi:10.1190/1.1440465.Archived fromthe original(PDF)on 2017-08-09.Retrieved2010-03-07.