Deciphering quaternary sediment dynamics: a synthesis of X-ray CT imaging and grain size endmember modeling

This study utilizes the capability of X-ray-computed tomography (CT) in the quantitative characterization of unconsolidated Quaternary sediments. Integrating CT scans with grain size endmember modeling (EMM) offers a novel approach to understanding sedimentological processes. The CT scans were analyzed to delineate Hounsfield Unit (HU) distributions, identifying four distinct density components reflective of varied sediment types. This classification, grounded in Gaussian mixture modeling, reveals intricate details of the sedimentary texture and its relation to depositional dynamics. The EMM further unraveled the textural complexity of the sediments, correlating CT-derived density variations with specific grain size fractions. This analysis illuminated the stratigraphic interplay between finer and coarser materials, indicative of alternating depositional energies within a dynamic fluvial-lacustrine setting. Principal Component Analysis (PCA) augmented this understanding, distilling the core’s complex sedimentology into principal factors that govern grain size distribution and density variations. Combining CT imaging with granulometric analysis provides a robust methodology for reconstructing depositional environments; this not only enhances our grasp of Quaternary sediment dynamics but also establishes a framework for future exploration in paleoenvironmental reconstruction.