Paleomagnetic Studies of Salt Domes

Wulf A. Gose, J. Richard Kyle

For the past several years, we have been pursuing a detailed paleomagnetic and petrographic study of the anhydrite cap rock of the Winnfield salt dome in Louisiana. This is the first such study ever undertaken and offers new insight into the timing of basinal and halokinetic processes. At Winnfield, periodic introduction of metalliferous fluids along the salt or anhydrite interface resulted in the formation of stratiform sulfide laminae, which contain the magnetic mineral pyrrhotite. Dense stratigraphic sampling of a 40-m section of the anhydrite yielded a magnetic reversal sequence that corresponds to sea-floor magnetic anomalies M22 to M20 (Kimmeridgian) and we were thus able to determine directly the age and rate of anhydrite accumulation. We recently sampled an additi nal 20 m of section at Winnfield and initiated a similar study of the Damon Mound, a salt dome in the Houston diapir province.

AAPG Search and Discovery Article #91030©1988 AAPG Annual Convention, Houston, Texas, 20-23 March 1988.