The Greenbrier Limestone, also known locally as the "Big Lime", is an extensive limestone unit deposited during the Middle Mississippian Epoch (345.3 ± 2.1 – 326.4 ± 1.6 Ma), part of the Carboniferous Period.

Greenbrier Limestone is in some places more than 400 feet (120 metres) thick, allowing it to trap large quantities of oil and gas.

Since this carbonate rock erodes quickly in the region's wet climate, outcrops are not prominent and are often quarried.

The limestones in this interval are predominantly skeletal grainstones or packstones.

This article about a specific stratigraphic formation in West Virginia is a stub.