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A.V. Applegate

Publications and source records attributed to A.V. Applegate.

2 recordsLinked to original sources

Structure and stratigraphy of the western Florida shelf; Part I, Multichannel reflection seismic data

This paper presents a synthesis of multichannel seismic data on the Western Florida shelf (Fig. 1). This work is part of an ongoing regional program conducted by the U.S. Geological Survey in studying the Exclusive Economic Zones of the United States. The data include 1270 km of 32-fold, common-depth-point (CDP), reflection seismic line obtained with a 3200 m, 64 channel, hydrophone streamer and a 2000 in 3 airgun array. The rationale for the line layout was to tie eight key exploration wells among the 14 existing in federal waters prior to 1980 to 4 key wells in Florida. An attempt was also made to connect our survey with that of the University of Texas Institute of Geophysics in the deep Gulf of Mexico basin. A second set of 1500 km of 24-fold CDP data were collected using a 1200 m, 24-channel streamer and a 550 in 3 airgun source. This set was intended to tie additional wells, drilled between 1979 and 1983, and to infill our original net. Gravity and magnetic measurements were also made along these lines. Our subsurface information in federal waters consists of well logs and files released to us initially by the Conservation Division of the U.S. Geological Survey and subsequently by the U.S. Minerals Management Service. Most information from wells in state waters was provided by the Florida Geological Survey. Table 1 lists wells included in our study and summarizes the types of logs and other information available from each well. Spontaneous potential or gamma ray, resistivity or conductivity, sonic and density logs were generally available. Lithologic information, paleontologic and log picks on stratigraphic units and dip-meter data were also common. Check shot surveys for velocity analysis were available in three wells.

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Subdivision and regional stratigraphy of the pre-Punta Gorda rocks (lowermost cretaceous-jurassic?) in South Florida

In recent years several wells have been drilled in the South Florida Basin through carbonate and evaporite sequences to depths as much as 5,300 ft below the Punta Gorda Anhydrite. The deepest well penetrated igneous basement rocks to a total depth of 18, 670 ft. Correlation of anhydrite beds below the Punta Gorda has revealed several thick anhydrite units (200 to 400 ft) with regional persistence. The pre-Punta Gorda section is subdivided into four easily identifiable units listed in order of increasing age — Lehigh Acres (lowermost Comanchean), Pumpkin Bay (upper Coahuilan), Bone Island (lower Coahuilan), and Wood River (Jurassic?) Formations, all newly named in this report. In addition, the Lehigh Acres is divided into the West Felda Shale (base), Twelve Mile, and Able Members which are also named and defined in this report. Geochemical evidence indicates that the Lehigh Acres unit and the upper part of the Pumpkin Bay unit contain the most likely source beds for petroleum. Only two production tests have been carried out in the basin in strata below the oil-productive Sunniland Limestone. One was through casing in a Wood River dolomite zone. It reportedly produced water and some gas. The other was a drill stem test in an upper Pumpkin Bay dolomite zone which produced only water. In the Gulf Florida State Lease 826Y (Permit No. 275), a moderately porous, 350-ft-thick Pumpkin Bay dolomite zone was observed. As this well is west of the axis of the basin, better reservoir conditions presumably exist on the West Florida shelf than onshore.

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