La Popa Basin
Stratigraphic and structural record of evaporite diapirism, La Popa basin and Coahuila foldbelt, Mexico
Introduction:
In October 2007, nine undergraduate and graduate students and five faculty from the University of Alabama traveled to La Popa basin, in northeastern Mexico, to examine superbly exposed structures and Lower Cretaceous to Lower Tertiary strata that record mobilization of Upper Jurassic Minas Viejas Formation evaporites. Diapiric evaporite structures in this basin are among the best-exposed analogs to subsurface hydrocarbon traps in the Gulf of Mexico and elsewhere. Objectives of this field-course were to:
- Obtain first-hand experience observing and interpreting the structural and stratigraphic features associated with evaporite diapirs
- Compare and contrast structure and stratigraphy associated with passive evaporite diapirism versus evaporite-detachment structures (evaporite-cored anticlines)
The University of Alabama Department of Geological Sciences is grateful
for generous financial assistance from George Lindahl, III
Logistics:
Students and faculty in The University of Alabama Fall 2007 Seminar in Tectonics [GEO 534/634] spent 4 days (Oct 11-14) examining stratigraphic and structural relationships northwest of Hidalgo, Mexico. Rental vans were used to obtain access to well-exposed geologic features in the mountainous desert along the east flank of the Sierra Madre Oriental. The participants spent three nights at Posada El Potrero Chico on the outskirts of Hidalgo.
Field Observations:
DAY TWO: Halokinetic stratigraphy adjacent to a passive evaporite diapir: El Papalote
DAY THREE: Evidence of halokinesis (salt moblization): La Popa weld
DAY FOUR: Evaporite detachment structures: El Potrero Chico