Sea Cliffs and Fronting Wave Cut Platform Originate

Sea Cliffs and Fronting Wave Cut Platform Originate in settings where there is a relative sea level fall - where land surface is rising at a faster rate than sea level is rising. West Cliff Drive, Santa Cruz, CA

Sea Cliff Retreat – Processes and Timing 1. Abrasion of a Basal Notch 2. Thresholded Failure 3. Comminution Lag Protective Feedback Figure from Hapke and Richmond, 2002, Marine Geology Episodic Sea Cliff Failure Retreat History

Sea Cliff Erosion – feedbacks* grain entrainment - abrasion - positive feedback beach development - wave energy dissipation - negative feedback

Correlation of Wave Runup and Sea Cliff Retreat after: Ruggiero et al. , 2001 What about influence of lithology?

Tectonically Active Margin: Santa Cruz Mountains and SF Peninsula Image courtesy of USGS / PG&E Cooperative Research

Monterey Canyon - tectonic offset Figure from Greene et al. , 1991

Erosional Geomorphic Features - Marine Terraces Note sharp edges of the modern (actively forming) sea cliffs and diffuse, scraps of terrace treads high in the landscape Highway 1 near Santa Cruz, California

Correspondence of Terrace Elevation with Age/SL highstand From Merritts and Bull, 1989, Geology

Marine Terrace Generation and Degradation* Animation by Robert S. Anderson: http: //geomorph. geology. ufl. edu/~adamsp/Outgoing/Animations/bobs_terrace_movie. mov

Isostatic Uplift and Landform Preservation Holocene Beach Ridges - Sweden isostatic uplift from deglaciation since late Pleistocene = 2 mm/yr

Isostatic Uplift of the Florida Platform

Karstostasy - Idealized Animation by Peter N. Adams: http: //geomorph. geology. ufl. edu/~adamsp/Outgoing/Animations/Fla. Epeir_Run 109. mov

Karstostasy – Application to Florida Through the Pleistocene Animation by Peter N. Adams: http: //geomorph. geology. ufl. edu/~adamsp/Outgoing/Animations/Fla. Epeir_Run 125. mov