Sustainable Exploration Of Critical Minerals: Integrated Magnetotelluric And Gravity Surveys For Lithium Pegmatite Targeting

Abstract

The global transition toward renewable energy has led to a sharp increase in demand for lithium, a critical element in energy storage technologies. Traditional exploration methods, often limited to shallow detection, are inadequate for identifying deep or structurally complex pegmatite-hosted lithium deposits. This study develops and tests an integrated geophysical approach combining magnetotelluric (MT) and gravity surveys to improve the detection of deep-seated lithium-bearing pegmatites in the Coconino Plateau region of north-central Arizona. Gravity anomaly analysis identified two low-density zones, Zone A (~1.2 km) and Zone B (~1.5 km), while MT resistivity imaging revealed corresponding high-resistivity features typical of coarse-grained, spodumene-rich pegmatites. Integrated interpretation showed strong spatial concordance between the datasets, improving confidence in anomaly classification. Structural analysis further indicated that both zones are aligned with regional faults, reinforcing the hypothesis of structurally controlled pegmatite emplacement. The results demonstrate that combining MT and gravity surveys provides a scalable, non-invasive exploration framework capable of reducing environmental disturbance compared to invasive drilling campaigns. Beyond advancing geophysical methodology, the approach contributes to sustainable resource exploration by enabling more accurate targeting of strategic minerals essential for clean energy technologies. While the study highlights methodological strengths, limitations include the use of partially synthetic MT data and the absence of drilling validation, which should be addressed in future work. This integrated workflow offers a model for environmentally responsible exploration in underexplored terrains, supporting global efforts to secure critical minerals for the clean energy transition.