New Sedimentary Rock Made from Coastal Slag Deposits in the U.K.

• Human activity has significantly altered the earth’s landscape, leading to the Anthropocene era.
• Industrial waste and construction debris have influenced the environment by altering soil and water acidity, soil composition, and mineral distribution.
• In 2015, artificial ground contributed over 316 million tonnes of sedimentary material to the oceans, exceeding the natural supply.
• A new kind of sedimentary rock has been documented from coastal slag deposits in the U.K., following other formations like molten glass and steel in the refuse of nuclear weapon tests and pieces of plastic floating in oceans.
• Slag is a major component of artificial ground, a composite material containing metal oxides and silicon dioxide, and is a by-product of the steelmaking process in the iron and steel industries.
• The lithification process hardens industrial waste, including slag, into sedimentary rocks, creating artificial ground.
• The sedimentary rocks with slag are relatively more abundant in the U.K. due to historical industrial activities.
• Slag is chemically stable and has the ability to neutralize acidity, and when lithified slag breaks down, it stores greenhouse gases like carbon dioxide through a process called mineral carbonation.
• Understanding how slag undergoes lithification is crucial to understanding how the deposits will behave over time, so that we may eventually maximize its carbon capture potential.
• Reusing slag to sequester carbon could reduce the industry’s carbon footprint.