27 Geological Surveys and Resource Mapping/Evaluation Studies (Posters)

This session highlights studies from state geologic surveys and the U.S. Geological Survey regarding natural resource evaluations. We welcome submissions with relevance to critical minerals, rare earth elements, various energy sectors, and the construction industry.

Tuesday, 10 March 2026
9:00 AM - 5:00 PM
RCC, Lower Level Hall

Ultramafic Rocks in Virginia: Potential for Carbon Mineralization and Critical Mineral Resources

Paper number: 27-2
Program: Technical Sessions
Time: 9:00 AM – 9:00 AM

Authors

Abstract

Ultramafic rocks contain calcium- and magnesium-rich minerals favorable for carbon mineralization and may also be enriched in nickel and cobalt, critical mineral elements that are important for the green energy transition. Two major types of ultramafic rocks are identified in Virginia. In the Blue Ridge and western Piedmont, talc chlorite schists of Neoproterozoic age outcrop as NE–SW striking lenses and belts, extending up to ~60 km within metasedimentary and metavolcanic rocks. In the southern Piedmont, small outcrops of metamorphosed pyroxenite occur as pods and lenses (up to 1km) within gneisses, metagabbro, and amphibolite. Field observations reveal that talc chlorite schist is fine- to medium-crystalline and ranges from relatively hard with a weak foliation to soft-soapy with a well-developed schistosity. Petrographic analyses indicate that these rocks contain chlorite, talc, and relict amphibole and pyroxene, with minor quartz. Metapyroxenite has a medium- to coarse-crystalline, massive to weakly foliated texture, and is composed primarily of pyroxene and amphibolite with chlorite, serpentine, and relict olivine. Both lithologies contain accessory opaque minerals, including chalcopyrite, pentlandite, and Cr- or Fe-oxides, as well as carbonate minerals including dolomite and calcite.

The ultramafic lithologies show enrichment in Ni, Co, and Cr, likely related to sulfide mineralization and regional hydrothermal activity. Although the talc chlorite schist overall has below ore grade concentrations of these critical elements, the broad surface extent of this unit suggests a larger potential resource. Several dimension stone and crushed stone quarries are developed in the talc chlorite schist, and their mine tailings could serve as an additional source for ex-situ carbon mineralization. Metapyroxenites have higher overall Ni, Co, and Cr, with one locality containing ore-grade concentrations of nickel. Limited surface exposure and varied petrogenesis histories make it difficult to access the distribution of metapyroxenite resources. A possible zone of nickel sulfide accumulation may occur beneath these ultramafic units and warrants further evaluation.

Geological Society of America Abstracts with Programs. Vol. 58, No. 1

doi: 10.1130/abs/2026SE-411722

© Copyright 2026 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.