Southwest Florida Coastal and Estuarine Environment  Response to Sea Level Change Over the Late Holocene

Chris Kitchen, Class of 2002

Dept. of Geology, Whitman College, Walla Walla, WA 99362

    Questions

        How has southwest Florida's coastal and estuarine environments evolved in response to sea level change over the late Holocene?  What are the implications for future environmental change?

       Can this environmental and sea level change be seen in the biofacies record?  How do these biofacies reflect environmental change and do they correlate to present day environments?  Does this contribute to evidence of sea level rise and fall?

         Hypothesis

         Biofacies will reflect sea level and corresponding environmental change by the presence of certain indicator species.  These biofacies will show the overall transgressive sequence and will also show high frequency regressive periods.  From these biofacies, I will be able to determine the current rate of rise.

        We can use the past as a key to the present to determine if relative sea level is currently rising or falling and the effects of these on estuarine environments.  We can also use this information as target restoration indicators of success and how stable coastlines are in the face of transgression.

        Study Area

        I conducted my research on Rookery Bay and the 10,000 island areas of southwest Florida. Specifically, the area of study is a transect from the Blackwater river out past Hog Key into open ocean.  This area includes river, estuarine, lagoon, bay, brackish water, intertidal, and marine environments.

        Methods

      I used a 3 cm diameter aluminum irrigation tubes that are 732 cm long.  We used a vibrator head to core and bore them through the Holocene sediment as far as possible and pull them out with a tripod using a system of come-alongs and winches.  I cut these cores open in the lab to describe and sample them.