Regional Sequence Stratigraphic Setting of Miocene-Pliocene Sediments, Veracruz Basin, Mexico
Marco A. Arreguin-Lopez and Paul Weimer
University of Colorado, Boulder, Colorado
This study focuses on the sequence stratigraphy of the Miocene-Pliocene deposits in the Veracruz basin. It is based on an interpretation of 2160 km of 2 dimensional and 590 square km of 3 dimensional seismic data, 27 wireline logs and 16 wells with biostratigraphy. Ten stratigraphic intervals were identified and interpreted ages range from 20.6 Ma to 3.8 Ma.
The initial sedimentary fill into the basin, 20.6-10.75 Ma, reflects a deep foreland fill. The basin consisted of folded highs around its flanks and structural lows. Pre-existing bathymetric highs affected the distribution of sediments derived primarily from the west through a series of canyon systems cut between preexisting folds. Depositional systems change regionally from channel-fill and overbank to the west to channel-fill, overbank, and sheet deposits on the eastern margin.
Between 10.75-6.2 Ma, the basin was deformed by a series of rising anticlines, which were underlain by thrust faults. The development of these bathymetric highs segmented the depositional systems. The canyon systems on the western margin fed sediment to the basin and deposited primarily in channel fill and overbank settings that changed basinward to lobes. The uplifting structures acted as barriers to turbidite flow. The channel and overbank deposits pinched out on the eastern margin of the basin.
By 6.2-3.8 Ma, significant deltas had developed to the north, supplying most of the basin sediment, and only minor sediment in the west. Deepwater deposition occurred in the middle to southern basin area. Channel-fill and overbank deposits predominated, onlapping the distal southern margin.
AAPG Search and Discovery Article #90032©2004 GCAGS 54th Annual Convention, San Antonio, Texas, October 10-12, 2004