La Formación Carbonera y sus implicaciones tectónicas, estados de Coahuila y Nuevo León

http://dx.doi.org/10.18268/BSGM1989v50n1a1

Samuel Eguiluz de Antuñano*

• PEMEX. Exploración Z. NE.

Abstract

The mountain ranges situated on the Curvature of Monterrey, between Monterrey and Saltillo cities, northeastern Mexico, exhibit a sandstone sequence that was the base to fundament the existence of a landmass during the Jurassic.

Former studies had situated the clastic rocks within La Casita Formation. New studies have founded that the sandstone contains ammonites of Neocomian age.

In this paper it is made the distinction between two siliciclastic sequences, assigning the upper part to the Carbonera Formation. 1t is proposed in this paper the name Carbonera for a siliciclastic rocks of Neocomian age of diverse environments situated on the austral margin of the Coahuila paleoisland, the sequence overlay La Casita or Taraise Formations and underlay Cupido or Virgen formations. The Carbonera Formation correlates with Hosston, San Marcos, Las Vigas and Barril Viejo Formations.

The deposits of Carbonera Formation in the Monterrey-Saltillo area and their regional correlation in other basins of northern Mexico, suggest that the sedimentary event was synchronous and has close relationships with global eustatic sea level changes.

Geophysical and geological data suggest the structural continuity between the Muertos, San Lucas and Arteaga anticlines in the east, and their extension to the west. The deformation style is a transitional zone between the Sabinas basin and the fold and thrust belt of Parras area.

Configuration of magnetic basement, seismology, gravity data and petroleum wells information, confirm the idea postulated before by many authors to consider the southern limit of the Coahuila block as a paleochannel situated between the Mexican interior Basin and other basins to the east.