Ejecta Layer
A widespread layer of ejecta, believed to be from the Acraman crater, is found within Ediacaran rocks of the Flinders Ranges at least 300 km east of the crater, and in drill holes from the Officer Basin to the north. At the time these areas were shallow sea, and the ejecta settled into mud on the sea floor. The ejecta contains shocked minerals and small shatter cones, is composed of rock similar in age and composition to that at the crater, and is associated with an iridium anomaly suggesting contamination with extraterrestrial material. An evolutionary radiation within marine microorganisms (acritarchs) occurs just above the level as the ejecta layer, and some authors believe there may be a connection. The proximity of the crater to the type area for the Ediacara Biota is noted, though probably not significant given the likely global consequences of the impact.
Read more about this topic: Acraman Crater
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