CEED Head

Marathon Fold Belt

The Marathon Belt is a world-class laboratory for studying the sedimentation and deformation in a Paleozoic orogen.

Here one can observe spectacular exposures illustrating shifting sedimentary patterns and source areas as the region was progressively deformed during the Paleozoic. Deep water basins fill as an island arc grows and thrusting is initiated eventually culminating in a collision with an exotic terrane. Resistant novaculite causes the structures to be well-preserved and stand out in bold relief. Studies initiated by P. B. King and continued by students and faculty at the University of Texas give us an excellent understanding of the well-exposed strata. Published studies by petroleum geologists provide an unusual complementary picture of the third dimension.

1mara_marathondem
Digital Elevation Model of part of the Marathon Basin showing some of the spectacular folding.  Width of image is 21 miles.

2mara_novaculitefold
View of an anticline in the Caballos Novaculite. This distinctive light-colored rock unit in the Marathon Belt is correlated with novaculite in Arkansas in the Quachita deformed belt.

 

3mara_marathonxsect


A cross-section illustrating the structural complexity in the Marathon Belt

 (from LaRoche & Higgins, 1990)