278 Understanding Temporal Dynamics in Hydrogeochemistry and Sedimentary Processes in Estuarine Environments

This session explores temporal changes in estuarine environments with respect to water chemistry and sediment inputs. Effects of evolving physiochemical properties and isotopic composition of water, as well as the geochemical attributes of sediments on the environment will be presented.

Wednesday, 22 October 2025
1:30 PM - 5:30 PM
HBGCC, 213AB

Multi-Proxy Analysis of Sediment Dynamics and Inputs in the Wouri Estuary

Paper number: 278-11
Program: Technical Sessions
Time: 4:20 PM – 4:35 PM

Authors

Abstract

Understanding sediment dynamics and input sources in estuaries is essential for effective environmental management and conservation. This study investigates the historical sediment flux and source inputs in the Wouri tropical estuary, Cameroon, using two 78 cm sediment cores collected from tidal flats on the eastern and western flanks of the estuary.

The cores were analyzed for grain size and color variation, organic matter content using the Loss on Ignition (LOI) method, and elemental composition via wavelength-dispersive X-ray fluorescence (WDXRF). Elemental enrichment factors were calculated relative to average crustal abundance and compared between the two locations.

The eastern core revealed three stratigraphic sections: a lower fine-grained unit (organic matter: 7.9 – 13.5%), a middle layer with mixed fine and coarse grains (4.8 – 7.7%), and an upper coarse-grained section (0.9 – 1.8%). The western core displayed two sections: a lower medium-grained layer (3.6 – 4.6%) and an upper coarse-grained layer (1.9  – 2.1%). These variations in grain size and organic matter content indicate shifts in depositional energy, suggesting a historical tidal energy asymmetry across the estuary.

Elemental analysis showed moderate to very high enrichment of antimony (Sb) and molybdenum (Mo) throughout both cores. Cobalt (Co) and arsenic (As) were also moderately to significantly enriched in the eastern core, while moderate Co enrichment was noted only in the upper 15 cm section of the western core. These findings suggest spatial variation in sediment input sources, likely influenced by river discharge dynamics and varying anthropogenic pressures within the estuarine catchment.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6

doi: 10.1130/abs/2025AM-412296

© Copyright 2025 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.