Using Ground Penetrating Radar to Determine Stratigraphic Architecture of the Cooloola Sand Mass, Southeastern, Queensland, Australia
Michael Levenson
Advisor: Dr. Allen Gontz
Friday May 4th, 2018
CSL 422 – 11 to 11:20 am
watch Michael’s defense
Abstract
The Cooloola Sand Mass (CSM) is a major coastal dunefield situated within the Great Sandy Region of southeast Queensland, Australia and forms part of the terminus of the longest downdrift system of siliceous clastic sediments on the planet. The CSM is orientated roughly north-south. It extends 65 km and varies in width from less than 1 km to greater than 25 km. It is composed almost entirely of unconsolidated aeolian sands with parabolic dunes, blowouts, and degraded dune systems. The highest dunes reach 240 m above sea level and the entire sand sheet thickness is thought to be at least 500 m, if not 800 m thick. Other researchers have focused on understanding the soil stratigraphy of the thick, > 30 m podzols and timing of dune emplacement. The oldest dune forms date to 1.2 mya. Despite the extensive nature of these sand deposits, both the timing and causes of dune activation and stabilization remain little investigated. In this paper, a small subset of GPR data from the western side of the CSM was analyzed to examine the stratigraphic relationship of the high eastern dunes with the lower-elevation plain to the west and relationship to regional climate variations. The GPR data revealed a suite of stacked GPR facies suggestive of a migrating sand sheet with linear dunes. The stacked facies range in thickness from ~3 m to > 9 m. The varying thickness is potentially related to sediment availability and wind strength.