English: Vein in weathered shales in the Devonian of Kentucky, USA.

These are weathered shales in the New Albany Shale, a Devonian-aged formation in Kentucky, Indiana, Illinois, and eastern Missouri. The unit is dominated by dark-colored marine mudshales of Late Devonian age. These black shales were deposited in a moderately deep, anoxic seafloor environment. This was a widespread lithofacies during the Late Devonian's Global Anoxia Event. The New Albany Shale is equivalent to the Ohio Shale, the Antrim Shale, and the Chattanooga Shale in surrounding states.

The New Albany Shale's member terminology varies from region to region. In southern Indiana and adjacent areas of Kentucky, the New Albany consists of (from the base upward): Blocher Member, Selmier Member, Morgan Trail Member, Camp Run Member, and Clegg Creek Member.

The wall seen here has an obvious, vertically-oriented vein cross-cutting the shales. The vein intruded when the surrounding shales were semi-solidified. Vein fills are squished, contorted, and telescoped vertically - the vein compacted when the shales had not completed compaction themselves. It's estimated that the vein compacted when the shales had 20 to 30% porosity, at about ~500 meters burial depth. Vein fill materials include quartz (SiO2), calcite (CaCO3), dolomite (CaMg(CO3)2) and a trace of bitumen. Vein intrusion is related to large-scale fluid migration from basins to high areas (regional arches). The vein's host rocks are the upper Camp Run Member and the Clegg Creek Member.

Stratigraphy: upper New Albany Shale, Famennian Stage, upper Upper Devonian

Locality: roadcut along the western side of the south-bound entrance ramp to Interstate 65 at the Route 245-Interstate 65 interchange, north-northeast of Belmont & south of Sherpherdsville, south-central Bullitt County, north-central Kentucky, USA (37° 55' 24.45" North latitude, 85° 41' 18.33" West longitude)