Bulk carbonaceous chondrites display a deficit of approximately 100 parts per million (ppm) in 144Sm with respect to other meteorites and terrestrial standards, leading to a decrease in their 142Nd/144Nd ratios by approximately 11 ppm. The data require that samarium and neodymium isotopes produced by the p process associated with photodisintegration reactions in supernovae were heterogeneously distributed in the solar nebula. Other samarium and neodymium isotopes produced by rapid neutron capture (r process) in supernovae and by slow neutron capture (s process) in red giants were homogeneously distributed. The supernovae sources supplying the p- and r-process nuclides to the solar nebula were thus disconnected or only weakly connected.

Martian meteorites from a single Mars ejection site record 2 billion years of magmatic activity.

The application of 87Sr/86Sr in prehistoric mobility studies requires accurate strontium reference maps. These are often based from present-day surface waters. However, the use of agricultural lime in low to noncalcareous soils can substantially change the 87Sr/86Sr compositions of surface waters. Water unaffected by agriculture in western Denmark has an average 87Sr/86Sr ratio of 0.7124 as compared to an average of 0.7097 in water from nearby farmland. The 87Sr/86Sr ratio obtained from samples over 1.5 km along a stream, which originates in a forest and flows through lime-treated farmland, decreased from 0.7131 to 0.7099. Thus, 87Sr/86Sr-based mobility and provenance studies in regions with low to noncalcareous soils should be reassessed. For example, reinterpreting the iconic Bronze Age women at Egtved and Skrydstrup using values unaffected by agricultural lime indicates that it is most plausible that these individuals originated close to their burial sites and not far abroad as previously suggested.

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