Thin section photomicrograph (plane-polarized light) of calcite (stained pink with Alizarin Red S)
filling irregular vugs inferred to be former evaporite nodules in the basal Seven Rivers Fm. Note the
cloudy, geopetal fabric within the calcite — the "cloudy" material consists of kaolinite booklets
that have fallen to the bottom of the vugs when the evaporites were leached. Sample from outcrop
along New Mexico Highway 137 in western Rocky Arroyo, Eddy Co., New Mexico.
Long axis of photograph = 3.5 cm.

© Peter A. Scholle, 1999

Guadalupe Mtns. geology —— Scholle home page —— NM Bureau staff page —— NM Bureau main page