Extraterrestrisk och terrestrisk kromrik spinell i fanerozoiska kondenserade sediment
… to Earth during a part of middle Ordovician. From an early Paleocene marine sedimentary sequence with known sedimentation rate in Zumaia, northern Spain, 90,5 kilogram of condensed limestone, dated to about 63 Ma, was sampled. The limestone was dissolved in hydrochloric- and …