Classification of sedimentary furrows and a model for furrow initiation and evolution.

Sedimentary furrows are longitudinal bed forms which form in fine-grained, cohesive sediments of the deep-sea floor as well as in similar sediments in estuaries and in large lakes. Deep-sea furrows have been observed where bottom currents often flow in one direction at 5-20+ cm/sec. Those developed in muddy, cohesive sediments tend to have steep walls and flat floors, while those developed in carbonate-rich cohesive sediments are broad and have gently sloping walls. A model for furrow initiation and development in muddy cohesive sediments suggests that furrows develop in depositional environments swept by recurring, directionally stable, and episodically strong currents. Dissolution may play an important role in the formation and evolution of furrows in carbonate-rich cohesive sediments.-Author