The timescale of the modification stage basin-sized impact structures is not well understood. Owing to ca. 10 km erosion since its formation, Vredefort structure, South Africa, an ideal testing ground for deciphering post-impact modification. Here, we present geophysical and geochemical evidence from Granophyre Dikes, which were derived - now eroded melt sheet. dikes have been studied mostly in...

Abstract Recent observations and geophysical studies at the Vredefort impact structure have indicated that melt dikes in central uplift of small depth extents. In this study, we performed magnetic electrical resistivity tomography (ERT) surveys Lesutoskraal granophyre dike (LGD) trenched to confirm its extent. The ERT survey showed outcrops LGD are associated with shallow resistive zones <3 ...

The Sonju Lake intrusion (SLI) is a 1200-m-thick, shallow-dipping, sheet-like intrusion that forms part of the Beaver Bay Complex (RI-58, Chapter 7). Although its exposed strike-length is only about 3 km (Fig. 3-1), the SLI has a distinctive aeromagnetic signature that can be traced for at least 20 km beneath a cover of glacial drift. The nearly constant width of its aeromagnetic anomaly sugges...

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, petrographi...

Breccias and melt rocks found at possible meteorite impact structures on Earth may contain a minor extraterrestrial component. In the absence of evidence of shockmetamorphic effects in such rocks, the unambiguous detection of an extraterrestrial component can be of diagnostic value regarding the impact origin of a geologic structure. Previously the concentrations of siderophile elements, mainly...

Few studies in Australia have employed automated mineral techniques to augment archaeological site investigations, and there are no known published micromorphological of Australian shell midden sites. This pilot study presents results a micro-analytical investigation Tegillarca granosa (formerly as Anadara ) the Old Geos site, located an elevated location on Burrup Peninsula NW Australia. Analy...