File:High-temperature Fe-rich impact-related spherules (41598 2018 38089 Fig5).png

English: Group 1 SEM Images: High-temperature Fe-rich impact-related spherules. (a–f) High-temperature impact spherules have distinctive dendritic surface texturing indicative of rapid quenching from melt temperatures above ~1450 °C. SEM-EDS analyses for each spherule are in Supplementary Table S7. Elemental composition of spherule in (b) is in Supplementary Fig. S6. (g) Photomicrograph of high-temperature impact-related spherule illustrating the difficulty in distinguishing these from framboids (Fig. 11a) and detrital grains (Fig. 11c). Note percentages of Fe and O at lower right of some images. The composition of these spheroids is FeO (wüstite), a highly reduced mineral that almost never occurs under natural terrestrial conditions, but is common in meteorites and materials produced during impact events under oxygen-deficient conditions.