Investigating Self-Organization of Modern Reefal Landscapes Using a Cellular Automata Model

As can be observed from satellite, many aspects of modern carbonate depositional systems are self-organized. However, understanding of the processes that generate this distinctive behavior remain elusive. In an effort to match process to self-organized geometry, we present a 3-D forward model of reef growth using cellular automata. This model simulates reef growth and distribution of skeletal debris over spatial extents of several sq. kilometers and runs through time scales of several millennia. Classes in the model include, but are not limited to, branching and massive corals, algal hardgrounds, and unconsolidated sand. Model variables include sea level, initial topography, light intensity, and life history traits for the biological facies. Processes incorporated within the model include mortality and colonization rates for biological classes, transition probabilities between facies, and rates of vertical accretion. Together, these result in a self-organized landscape that emulates those observed in nature, such as rims, reticulate structures, and debris aprons. The results are visualized by accessing topographic and facies maps generated at user-determined time intervals. The goals of this work are to 1) investigate which configurations of environmental parameters result in specific spatial motifs, 2) examine the effects of environmental perturbations on reef construction, and 3) understand the importance of biological and physical regimes on the generation of geomorphological features.

AAPG Search and Discovery Article #90142 © 2012 AAPG Annual Convention and Exhibition, April 22-25, 2012, Long Beach, California