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Interactions between surface water and groundwater (hyporheic exchange) influence water quality and control numerous physical, chemical, and biological processes. Despite its importance, hyporheic exchange and the associated dynamics of solute mixing are often difficult to characterize due to spatial (e.g., sedimentary heterogeneity) and temporal (e.g., river stage fluctuation) variabilities. This study coupled geophysical techniques with physical and chemical sediment analyses to quantify hyporheic exchange dynamics in a compound bar deposit within a gravel-dominated river system in southwestern Ohio. Electromagnetic induction (EMI) was used to quantify variability in electrical conductivity within the compound bar. A zone of high electrical conductivity was clearly identified as a fine-grained cross-bar channel fill. Differences in the physical and geochemical characteristics of such channel fills play an important role in hyporheic flow dynamics and nutrient processing. EMI informed locations of electrode placement for time-lapse electrical resistivity imaging surveys to examine changes in electrical resistivity driven by hyporheic exchange, revealing preferential flow paths through high-permeability sediments. Grain size analyses confirmed interpretations of geophysical data, and loss on ignition and x-ray fluorescence identified more favorable locations for enhanced geochemical and microbial activity as cross-bar channel fills identified through EMI measurements. These findings provide fundamental insights into hyporheic exchange, and the technical framework presented in this study has implications for improving future studies of hyporheic dynamics and numerical model development through more accurate representation of geomorphologic features and sediment heterogeneity.