Strangways is a large impact structure, the eroded remnant of a former impact crater, located in the Northern Territory of Australia about east-south-east of the town of Mataranka. It was named after the nearby Strangways River. The location is remote and difficult to access. Its age has been determined as approximately 646 Ma. Description The circular topographic feature that marks the site was originally thought to be volcanic, with an impact origin first proposed in 1971 after the discovery of evidence diagnostic of impact including shatter cones and shocked quartz. The circular topographic feature is about in diameter and lies within Mesoproterozoic sedimentary rocks of the McArthur Basin. However, this is only a relic of the original crater after considerable erosion. Estimates of the original rim diameter vary between different researchers in the range ; the Earth Impact Database prefers a diameter of . The age of the impact event has been determined at 646 ± 42 Ma (Neoproterozoic) based on radiometric dating of impact melt rocks. In 1996, the crater's site was listed on the now-defunct Register of the National Estate. See also List of impact craters in Australia References Impact craters of the Northern Territory Proterozoic impact craters Precambrian Australia Geology of the Northern Territory Northern Territory places listed on the defunct Register of the National Estate