Textural Studies of Graded Bedding. Observation and Theory

SUMMARY Published data and new observations from the Tertiary and Ordovician show that non‐multiple, continuously graded beds from turbidite sequences have size decline curves that are either convex, concave, or straight. Utilizing a physical model and knowledge of fluid mechanics of turbulent transport, a formula relating both median and maximum grain‐size to height above the base of the graded bed was obtained. This analysis suggests that the shape of the size decline curve in a continuously graded bed depends on the initial size distribution of particles carried by the turbulent current.