Litho-structural control of Ambar crater in Deccan Trap, India

Abstract The morphology and preservation of impact craters are strongly influenced by the mechanical properties and structural architecture of the target rocks. This study examines the litho-structural control on the morphology of the Ambar impact crater formed within the Deccan Trap basalts of Maharashtra, India. Multi-source remote sensing data, including satellite imagery were integrated with GIS-based morphometric analysis and detailed field investigations to characterize lithological variations, structural elements, and crater geometry. Morphometric parameters such as crater diameter, rim height, wall slope, curvature, and circularity index were quantitatively evaluated and correlated with mapped basalt flow units and fracture networks. The results reveal pronounced spatial variations in rim morphology and slope stability that coincide with flow contacts, joint density, and lineament orientations. Zones of enhanced erosion and rim degradation preferentially follow pre-impact structural weaknesses rather than impact-generated features alone. These observations indicate that lithological heterogeneity and inherited structural fabric exert a first-order control on the post-impact modification and present-day morphology of the Ambar crater. The study highlights the necessity of integrating litho-structural frameworks into impact crater analyses, particularly in layered volcanic terrains.