Major, Through-going Stylolites in the Lower Ordovician Goodwin Limestone, Southern Nevada: Petrography with Dating from Paleomagnetism

Abstract

ABSTRACT The Early Ordovician Goodwin Limestone, a shallow-water, miogeoclinal calcarenite that occurs in the southern Great Basin, has been studied paleomagnetically and petrographically at one site in the Desert Range, southern Nevada. Major, through-going stylolites that occur in the Goodwin are relatively late diagenetic features because they truncate or deform all other fabrics. Locally, development of these stylolites has caused major disruption of primary bedding owing to differential compaction around chert nodules. The Goodwin yields a well-grouped characteristic magnetization that can be no younger than Early Triassic; because this magnetization is not affected by the stylolitic compaction, however, the magnetization could not have been acquired penecontemporaneously with deposition ut rather must reflect remagnetization. In turn, the paleomagnetic data show that the stylolites had formed by Early Triassic time at the latest and were not affected by Mesozoic thrusting or Cenozoic Basin-and-Range deformation.