America Graben (Discarded)

Location

Eastern Pulaski County

References

Ross 1963, Heyl et al. 1965, Kolata et al. 1981

Description

The America Graben was described as part of a complex zone of northeast-trending faults that displace Paleozoic rocks beneath Mississippi Embayment sediments in southernmost Illinois (Ross 1963). From the distribution of Cretaceous and Tertiary deposits, Ross inferred recurrent displacements through the Eocene Epoch and possibly later. Heyl et al. (1965) showed the America Graben on a map, but presented no new evidence for its existence. Kolata et al. (1981), using additional subsurface data, showed fewer faults cutting Paleozoic strata and found no compelling evidence for Cretaceous or younger movement. Their map does not indicate a graben; therefore, the use of the name America Graben should be discontinued.