Post-Impact Faulting of the Holfontein Granophyre Dike of the Vredefort Impact Structure, South Africa, Inferred from Remote Sensing, Geophysics, and Geochemistry

Better characterization features borne from long-term crustal modification processes is essential for understanding the dynamics of large basin-forming impact structures on Earth. Within deeply eroded 2.02 Ga Vredefort Impact Structure in South Africa, melt dikes are exposed at surface. In this study, we utilized a combination field, remote sensing, electrical resistivity, magnetic, petrographical, and geochemical techniques to characterize one such dike, namely, Holfontein Granophyre Dike (HGD), along with host granites. The HGD split into two seemingly disconnected segments. Geophysical modeling both segments suggests that rock does not penetrate below modern surface deeper than 5 m, which was confirmed by later transecting construction trench. Even though textures clast content different segments, major element, trace O isotope compositions each segment indistinguishable. Structural measurements tectonic foliations granites, as well spatial expression suggest dike segmented an ENE–WSW trending sinistral strike-slip fault zone. Such offset must have occurred after solidified. However, structure has been affected any events occurred. Therefore, inferred segmentation consistent occurring post-impact environment. These may involved progressive uplift crater floor, adjustment craters Moon.