4 D2. Igneous and Metamorphic Processes — From Kimberlites to Meteorites (Posters)

Sunday, 9 March 2025
1:30 PM - 5:00 PM
Lower Level Lobby

INTRIGUING MINERALIZATION WITHIN ARKANSAS NOVACULITE ADJACENT TO MAGNET COVE AT THE VARNEDORE PROSPECT, MALVERN, ARKANSAS

Paper number: 4-6
Program: Technical Sessions
Time: 1:30 PM – 5:00 PM

Authors

Abstract

Alkaline igneous rocks of the Magnet Cove Alkaline Intrusive Complex (Magnet Cove) were emplaced during the mid-Cretaceous period into older, deformed Ordovician, Mississippian, and Devonian age country rocks of the Ouachita Mountains near modern-day Malvern, Arkansas. Recently, some intriguing mineralization has been discovered within the novaculite rocks immediately east of Magnet Cove at a small mine known as the Varnedore Prospect. The prospect is located approximately 500 m east of the boundary between Magnet Cove and surrounding Mississippian-Devonian Arkansas Novaculite rocks. Rock samples have been collected from two pits at the Prospect, and hand sample examination of these samples indicate the presence of known minerals such as brookite, limonite, smoky quartz, and goethite. Several additional minerals, however, are not easily identifiable by visual inspection alone. This project is focused on confirmation of known minerals and identification of unknown minerals occurring in this novaculite. Methods of analysis include petrographic analysis, scanning electron microscopy (SEM), and powder X-ray diffraction (XRD). Initial examination of three samples of quartz indicates multiple generations of crystallization that contain a variety of mineral inclusions within each generation. Given that the mineralization appears to be located primarily within fractures in the novaculite and the sampling location is close to Magnet Cove, the identification of minerals within the novaculite may help to elucidate a possible relationship between novaculite fracturing, mineralization within fractures, and the emplacement of nearby alkaline intrusive rocks.

Geological Society of America Abstracts with Programs. Vol. 57, No. 1

doi: 10.1130/abs/2025SC-408980

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