Analogue model of gravity driven deformation in the salt tectonics zone of northeastern Mexico
Por:
Gracia-Marroquin, Diego, Cerca, Mariano, Carreon-Freyre, Dora, Barrientos-Garcia, Bernardino
Publicada:
1 dic 2018
Categoría:
Geology
Resumen:
In the deep seated gravity-driven deformation systems of the Gulf of
Mexico contemporaneous extension and contraction of the overburden is
favored by mechanical decoupling from the basement along thick salt
sequences (up to 4 km). The up dip extension is located inland, on the
continental shelf of northeast Mexico, and is characterized by
extensional listric faults and roll-overs; the downdip shortening zone
is located at the deep waters and is characterized by a fold and thrust
belt detached above the salt layer. Two physical experiments are used to
discuss some aspects of these gravity-driven systems. The experimental
setup includes a motor-driven experimental table, an inclined brittle
basement (1 degrees), a silicone layer simulating the salt sequences,
and sand layers simulating the pre-kinematic Jurassic-Cretaceous strata
before Laramide shortening. Deformation resulted in further tilting of
the basement (3 degrees to 4 degrees). After the onset of deformation,
thin sand layers were added at regular time intervals simulating the
syntectonic sedimentation. The experiments reproduced the geometry of
the deformation at the frontal ramp characterized by a seaward vergent
thrust and its associated deformed region (the Perdido fold belt). The
fold and thrust belt localization was favored by the change in basement
inclination (a built-in slope change). Key elements interpreted in one
available section of the area were reproduced in the model: a) the
presence of an antithethic roll-over in the extensional zone and, b) the
basinward vergence of folds and thrusts observed in the downdip
shortening zone in the mexican Perdido fold belt.
Filiaciones:
Posgrado en Ciencias de la Tierra, Centro de Geociencias, Universidad Nacional Autónoma de México, Blvd. Juriquilla No. 3001, Juriquilla, Querétaro, C.P. 76230, Mexico
Laboratorio de Mecánica de Geosistemas, Centro de Geociencias, Universidad Nacional Autónoma de México, Blvd. Juriquilla No. 3001, Juriquilla, Querétaro, C.P. 76230, Mexico
Centro de Investigaciones en óptica A.C., Loma del Bosque No. 115, León, Guanajuato, C.P. 37150, Mexico
Univ Nacl Autonoma Mexico, Ctr Geociencias, Posgrad Ciencias Tierra, Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Univ Nacl Autonoma Mexico, Ctr Geociencias, Lab Mecan Geosistemas, Blvd Juriquilla 3001, Juriquilla 76230, Queretaro, Mexico
Ctr Invest Opt AC, Loma del Bosque 115, Guanajuato 37150, Mexico
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