CASE HISTORY OF BENTON FIELD, BOSSIER PARISH, LOUISIANA

Abstract

A regional gravity‐meter survey executed during the summer of 1943 along the eastern slopes of the Sabine uplift indicated the presence of a prominent minimum trend. The first traverse of a subsequent reflection seismograph survey in portions of Townships 20 and 21 north, Ranges 12 and 13 west, Bossier Parish, Louisiana, revealed strong critical west and north dips, after which the Benton structure was delineated by a moderate amount of seismograph work. Geophysical maps of the raw gravity configurations and two seismic control horizons are presented. A comparison of the base of the anhydrite control with the deeper seismograph horizon, later identified to be somewhat below the Bodcaw sand of the Cotton Valley series, demonstrates the shifting of the structural axes down dip with increased depth. The discovery well on the apex of the structure and 16 other development wells confirm the outline of the seismic Cotton Valley picture. The structure is an elongate anticline approximately seven miles long with an average width of two and one‐quarter miles. Although only 60 feet of closure on the “D” sand has been proven by drilled wells, it is evident that total closure must exceed 100 feet. The history of folding of the Benton structure reveals interesting comparison of the results of the local causative forces as opposed to the effects of regional tilting due to the Sabine uplift. The remarkable accuracy of the seismic data was chiefly responsible for the unusual development following discovery of the field which resulted in early unitization of leaseholds which later included mineral and royalty interests. This permitted very economical drilling costs and proper spacing and location of wells to secure efficient drainage.