Article: Algal growths in the Rhaetic Cotham Marble of southern England

The Cotham Marble horizon in the Upper Rhaetic of southern England includes the two well-known rocks, Landscape Marble and Crazy Cotham Marble. Previous hypotheses concerning the origin of Landscape Marble are listed and the widely quoted gas-bubble explanation is discussed critically. An algal origin is proposed for the Landscape Marble, and the Crazy Cotham Marble is shown to be a current-concentrated breccia.