POSSIBLE TSUNAMI DEPOSITS OF THE NORTHEAST COAST OF THE YUCATAN PENINSULA

With the use of LIDAR data, a large depositional feature, assumed to be a beach ridge, was revealed in the jungle on the northeast coast of Quintana Roo on Mexico’s Yucatan Peninsula. These beach ridges typically form on linear trends that parallel the coastline and were located 2 kilometers inland where the linear morphology of the beach ridges had been extensively broken. It has been suggested that either tsunami or extreme hurricane activity may have caused the extreme change in beach ridge morphology. However, the northeast coast of the Yucatan is not known to experience extreme events such as tectonic activity though hurricane activity is common. The purpose of this research was to determine the cause of the geomorphic disturbance of the beach ridges. Field methods included the collection of rock samples, geologic mapping, and georeferencing of beach ridge morphology. Rock samples were analyzed and geologic data georeferenced within a Geographic Information System. Spatial analysis of the LIDAR data and lab analysis of the geologic and geomorphic features revealed that the break in the linearity of the ridges was not a result of tsunami or hurricane activity but rather the natural process associated with changes in sea level.