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A study was made using seismic work to define stratigraphic features in the Tampico basin in Mexico. The Tampico basin is in northeast Mexico, south of Tampico. The objective of the study was to define stratigraphy features within the Mesozoic and Tertiary parts of the basin. The lithologic sequence includes (a) consolidated Tertiary sands and shales, and (b) Cretaceous clastics and limestones, shales, and sandstones. Oil in the area is produced from turbidites and conglomerates which fill paleocanyons of Eocene age. The paleocanyons appear in a fan form. The lithology in the Late Cretaceous and Upper Jurassic section displays no major structural features, except a regional dip toward the Gulf Coast which is conformable with the basement. Conventional multichannel common- epth-point (CDP) reflection seismic data were collected and processed in the area during 1977 to 1980. After a preliminary structural interpretation was made on data, a seismic line which ran transverse to a fan in a paleocanyon was selected to use as a base for a seismic stratigraphy study. This seismic line was reprocessed through wavelet processing sequence to produce a true amplitude section. The wavelet processing sequence was used to reduce distortions in the basic wavelet and to recover high frequences lost due to transmission and absorption effects. From the true amplitude section, seismic anomalies such as bright spots and flat spots were identified. Following this, the data were processed through a rigorous wave equation inversion to produce an interval velocity section which t en became the main tool for stratigraphic interpretation. Low velocity anomalies were encountered within the Eocene, the top and base of the Late Cretaceous, and the Upper Jurassic. These anomalies corresponded to those identified in the true amplitude section and are postulated to be oil-saturated zones. The anomalous zones were then mapped laterally using the other seismic sections in the area.
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