Complex nanospherulites of zinc oxide and native amorphous boron in the lunar regolith from Mare Crisium

During the study of tea-colored impact glass fragments from the sample of lunar regolith delivered to Earth by the Luna 24 automatic station by transmission electron microscopy, the composition variations of the previously described high-carbonaceous film, the presence of at least three composition types of glasses, and unusual nanospherulites with Zn-B-N-O composition were discovered. As a part of a nonuniform high-carbonaceous oxygen-bearing film, sites enriched in either Na, S, Si, or Ca were detected. All these sites, as well as the whole film, are electron-amorphous; however, crystalline graphite was also found. Two types of nanospherulites are composed of amorphous ZnO and regular interstratifications of crystalline ZnO and amorphous boron layers with insignificant participation of adsorbed nitrogen. It is supposed that the formation of zinc-boron nanospherulites was caused by a fast-flowing explosive process and probably was modulated by high-frequency acoustic oscillations in a cloud of evaporated high-temperature ionized gas during the impact event.