Basement structural controls on the Jurassic sedimentary sequences in the Tampico-Misantla basin, Northeastern Mexico from a 3-D seismic reflection study

Abstract

The Tampico-Misantla basin is a mature oil rich province in northeastern Mexico with large unconventional oil plays currently being revitalized. Results of a 3-D seismic reflection study of the basement and Jurassic sequences are used to analyze the basement influence on sediment sequence and basin structure, by mapping the seismo-stratigraphic horizons for the (Tithonian) Pimienta, (Kimmeridigian) Taman/San Andrés, (Oxfordian) Santiago, (Callovian) Tepexic/Huehuetepec and (Bathonian) Cahuasas formations. The basement is characterized by stepped NW-SE tilted blocks of horst and grabens. The upper section in horsts to the northeast is at depths of 3200 m, whereas the lower section at 6500 mbsl lies to the southwest. Blocks are bounded by planar and curved, high angle normal faults with NW-SE and NE-SW orientation that form a conjugated system active from the Triassic to upper Jurassic, with two major pulses during the Bajocian and the Oxfordian. Vertical slips of main faults are variable and may reach 2000 m. The basement blocks play a major role in defining the depositional systems, with the thickness and distribution of overlying sedimentary units. Based on our analysis the middle Jurassic stratigraphic units of the Cahuasas Formation were deposited predominantly in continental environments, and exhibit large thickness variations. The Callovian Tepexic and Huehuetepec Formations were deposited in transitional and shallow marine environments, with relatively uniform thickness and distribution. The Oxfordian to Tithonian Santiago, Taman/San Andres and Pimienta Formations were deposited in varying marine environments, showing a tendency of progressively pinching out against the paleotopographic highs. The thickness variation in the Santiago Formation suggests episodes of increasing subsidence and fault reactivation. The seismic volume modeling documents the basement structure and stratigraphy of the Jurassic sequences in the Tampico-Misantla basin.