The Influence of Neotectonic Activity on Groundwater System Dynamics in the Mambilla Plateau, Taraba State

The Mambilla Plateau in Taraba State, North East Nigeria, is one of the country's highest terrains and straddles active fault systems whose neotectonic influence on groundwater recharge, flow pathway geometry, and spring discharge patterns has not been investigated, representing a significant gap in understanding of groundwater systems in tectonically active highlands. This study investigates the influence of neotectonic activity on groundwater system dynamics in the Mambilla Plateau using a multidisciplinary approach combining geomorphic analysis, structural geology, hydrogeological monitoring, and isotope hydrology. Morphotectonic analysis of a high-resolution digital elevation model derived from ALOS-PALSAR radar imagery identifies active fault scarps, offset drainage channels, and anomalous knick points indicative of neotectonic activity. Structural fieldwork characterises fault kinematics and documents evidence for recent displacement. A spring inventory was conducted across the plateau, cataloguing discharge rates, temperature, electrical conductivity, and location relative to mapped structural features. Seasonal and inter-annual spring discharge time series were analysed to characterise storage and transmission properties of the aquifer system feeding each spring. Stable isotope and dissolved gas compositions of spring waters provide constraints on recharge altitude, mean residence time, and mixing between shallow and deep flow systems. The study tests the hypothesis that fault-controlled permeability pathways act as preferential recharge conduits, producing systematically higher-yield springs at structural intersections. Keywords: neotectonics, groundwater dynamics, Mambilla Plateau, spring discharge, isotope hydrology.