shale

sedimentary rock / source rock

Noun

This term describes a specific geological formation characterized by fissility, meaning the rock naturally breaks along parallel planes. It is often associated with dark colors due to high organic carbon content, which distinguishes it from lighter siltstones or sandstones. In modern industrial contexts, the word frequently appears in the phrase shale gas or shale oil. This refers to the hydrocarbon-bearing source rock rather than the rock itself, shifting the connotation from a purely geological description to one of energy extraction and hydraulic fracturing.

Meanings

Noun

A fine-grained sedimentary rock composed of clay-sized particles that splits easily into thin, flat layers.

"The geologist identified a thick layer of black shale in the canyon wall."

Noun

A type of sedimentary rock that contains trapped organic matter and can be fractured to extract natural gas or oil.

"The boom in the energy sector was driven by the development of shale gas extraction."

Last Updated: June 13, 2026•Report an Error