Petrobras, 1983. "Potiguar Basin, Brazil", Seismic Expression of Structural Styles: A Picture and Work Atlas. Volume 1–The Layered Earth, Volume 2–Tectonics Of Extensional Provinces, & Volume 3–Tectonics Of Compressional Provinces, A. W. Bally
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This seismic section is located in the central graben of the Potiguar basin, with a northwest to southeast direction. in its central part, there is a structural high called Alto de Quixaba (Quixaba High), originated during Lower Cretaceous time by an intense tensional tectonism. The Central Graben is filled with Neocomian lacustrine sediments, cut by a Cenomanian angular unconformity. The sedimentary sequence deposited from Cenomanian to Coniacian/Santonian, grades from fluvial clastics to shallow platform limestones.
The seismic data was recorded with DDS-888 48-channel equipment, using vibroseis as source (16 sweeps per point of vibration, weighted array; 64 sweeps in 100 m, or 328 ft), and 36 geophones per station (180 m, or 591 ft, long array, 36 geophones per station). Coverage was 24fold and maximum offset was 1,350 m (4,420 ft).
This chapter depicts a northeast to southwest seismic line located in the central part of submerged Potiguar basin. Horizon 3 (interpreted time section, offshore) represents the top of a "rift" sequence (Aptian) which is affected by normal faults. Horizon 2 indicates the top of a carbonate transgressive sequence (Turonian to late Campanian) interbedded with shales and sandstones. Horizon 1 shows the base of Tertiary regressive platform sequence. The interval between reflectors (1) and (2) constitutes the shale, sandstone, and turbidite slope sequence.