HR: 16:35h
AN: U34A-02 [Abstracts]
TI: Structural Imaging and Petrophysics of Chicxulub Impact Crater From Instantaneous Seismic Attributes
AU: * Salguero-Hernandez, E
EM: salguero@geofisica.unam.mx
AF: Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Circuito de la
Investigación Cientifica s/n, Mexico City, D.F 04510, Mexico
AU: Urrutia-Fucugauchi, J
EM: juf@geofisica.unam.mx
AF: Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Circuito de la
Investigación Cientifica s/n, Mexico City, D.F 04510, Mexico
AU: Ramirez, L C
EM: lcramire@imp.mx
AF: Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas 152, Edif. Sismologia,
Cub.105, Mexico City, D.F 07730, Mexico
AB:
Over the past two decades, Chicxulub impact crater has been studied with a wide array of geophysical
techniques, drilling with continuous core recovery and high-resolution marine seismic surveys, with the purpose
of investigating crater structure, crater stratigraphy and impact lithology characterization. In our study, we use for
the first time seismic attributes to further analyze the marine seismic data. Seismic attributes are a powerful tool
to enhance information; computing complex seismic traces and petrophysical characterization. Instantaneous
seismic attributes amplitude envelope, frequency and phase are useful in correlating seismic events even
thought accurate interpretation would be difficult if there are no calibrated synthetic data. Conventional
instantaneous attributes were computed for two 2D long seismic profiles Chicx-A and Chicx-A1, which run E-W
across the crater. The three instantaneous seismic attributes are consistent in showing major crater
characteristics: (1) Tertiary carbonate-impact breccia contact inside the basin presents a continuous high-energy
anomaly with higher frequencies than the Tertiary reflectors or melt; (2) most of the transient cavity shows as a
large zone of higher frequencies compared to outside the basin at the same two-way travel time; (3) two fracture
zones in the slumped blocks are observed as two zones of low energy and low frequency; (4) breccias outside
the basin present a peculiar seismic signature in the phase attribute, sharply contrasting from Tertiary and
Cretaceous signatures; and (5) the phase attribute permits recognition of continuity of several Tertiary and some
Cretaceous reflectors.
DE: 0902 Computational methods: seismic
DE: 0910 Data processing
SC: Union [U]
MN: 2007 Joint Assembly