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17 High concentrations of extraterrestrial iridium have been reported in terminal Sturtian and 18Marinoan glacial marine sediments and are used to argue for long indicate a return to more fully oxygenated seawater in the aftermath of the Marinoan snowball 28 earth. Sections dominated by hydrogenous osmium indicate increasing submarine hydrothermal 29 sources and/or continental inputs that are increasingly dominated by young mantle-derived rocks 30 after deglaciation. Sedimentation rate estimates for the basal cap carbonates yield surprisingly 31 slow rates of a few centimeters per thousand years. This study highlights the importance of 32 using sedimentary rock samples that represent sufficiently large area-time products to properly 33 sample extraterrestrial particles representatively, and demonstrates the value of using multiple 34 tracers of extraterrestrial matter. 35