Examining the Stratigraphy of the Beaches and Dunes
Ground penetrating radar (GPR) is a non-intrusive geophysical instrument that emits an electromagnetic pulse into the ground at a given frequency and records the return signals generated by contrasts in subsurface sediments. Processed GPR data produces imagery of the that is useful for sedimentological or stratigraphic studies. We have been collecting GPR at Sandy Hook’s most rapidly growing beach to study how wind, waves, tides, and currents are moving sand to create the coastal landforms that comprise the beach today. Integrating these geophysical data with centimeter-accurate topographical data collected with GNSS (global navigation satellite system) survey equipment provides constraints on the ages (<20 years) of the interpreted stratigraphic surfaces. Sediment samples collected from shallow excavations ground-truth interpretations and provide insight regarding the sedimentological characteristics of the beach deposits. Through this work, we are able to generate historical records of storm-driven erosion events and analyze how the beach recovers post-storm.
