Li, and 10 co-authors, reported in 2018 that the Dhala structure in Central India has been a topic of global interest ever since the report of an ancient meteorite impact event there. The authors presented an integrated study of the petrology, geochemistry, and zircon U-Pb zircon geochronology and rare earth element geochemistry from the structure along with and an analysis of the grain morphology and textural features.
The authors provide new insight into the nature and timing of the impact event. The zircon grains from the impactites show textures typical of shock deformation which the authors correlated with the impact event. The authors also identified the presence of reidite based on Raman spectroscopy and characteristics such as a persistent planar fracture, bright backscattered electron images, and a lack of zoning, which are all diagnostic features of this mineral formed during an impact event. The authors' zircon U-Pb data from the various rock types in the basement show magma emplacement at ca. 2.5–2.47 Ga, and the Pb loss features suggest that the impact might have occurred between ca. 2.44 Ga and ca. 2.24 Ga.
Another minor group of late Paleoproterozoic zircons with concordant ages of 1826 and 1767 Ma in the brecciated quartz reefs along the margins of the impact
crater from unfractured grains represent an younger thermal event after the impact. The rare-earth element patterns of the Neoarchean to early Paleoproterozoic zircon population reflect the effects of hydrothermal alteration on a peralkaline host rock. The abnormally high concentration of K2O in the impactite (up to 15.91 wt%), is also
consistent with metasomatic alteration associated with the impact event
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