Discovering Coastal Processes Coastal areas are geologically dynamic and shaped by processes related to both internal processes such as tectonism, volcanism, and isostacy and surficial processes such as wave erosion, mass wasting, and cliff retreat. In this activity we will look at two case studies chosen to investigate the effects of both internal and surficial processes. The first case study looks at subsidence in the Hawaiian Islands based on data from drowned coral reefs, while the second deals with coastal erosion along the Oregon coast. For each part of the activity you will be looking at real data and asked to draw conclusions based on your analysis.