Backus, Milo M., 1932-2014-10-242018-01-222014-10-242018-01-221980-12http://hdl.handle.net/2152/26894textThe presence of gas and oil in some sand formations decreases the seismic velocity and density to such an extent that anomalously large reflections coefficients are encountered at fluid contacts. Geerstma and Gassmann's theories are equivalent and provide a good way to study the physical properties that affect the elastic behavior of the porous rock. The fluid-contact reflectivity (gas-water, oil-water) can be well estimated based on the brine saturated velocity alone. A comparison between the estimated and observed fluid-contact reflectivities on seismic and well log data from an Offshore prospect showed a remarkable agreement.electronicengCopyright is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.Seismic reflection methodPetroleum in submerged landsPetroleum--GeologyNatural gas--GeologyThesis