1: Pre-Nectarian lunar craters (e.g., Ryder, 1989; Taylor, 1992)
2: Erathosthenian craters (e.g., McEwen et al., 1997)
3: Proterozoic impacts, Australia (Shoemaker & Shoemaker, 1996)
4: Lunar farside rayed craters (McEwen et al., 1997)
5: US Mississippi lowland craters (Shoemaker, 1977)
6: Early Ordovician meteorite flux estimate (Schmitz et al., 1996, 1997)
7: Cenozoic ET matter flux, Os isotope model (Peucker-Ehrenbrink, 1996)

Compilation of terrestrial accretion rates of extraterrestrial (ET) matter through time. Note high accretion rates of meteorites and cosmic dust in the early Ordovician. See Schmitz et al. (1997) for discussion.

Compilation of Cenozoic terrestrial accretion rates of ET matter. See Peucker-Ehrenbrink et al. (1994) and Peucker-Ehrenbrink (1996) for references and discussion.

Accretion rates of ET matter over the past 80 Ma, calculated using a four component Os isotope mixing model (see Peucker-Ehrenbrink, 1996, for discussion). Lower diagram is a blow-up for the time span 0-7 million years.

Publications:

Peucker-Ehrenbrink, B. (1996). Accretion of extraterrestrial matter during the last 80 million years and its effect on the marine Os isotope record. Geochim. Cosmochim. Acta, 60, 3187-3196.

Schmitz, B., B. Peucker-Ehrenbrink, M. Lindströem and M. Tassinari (1997). Accretion rates of meteorites and cosmic dust in the early Ordovician. Science, 278, 88-90.

Peucker-Ehrenbrink, B., G. Ravizza and A.W. Hofmann (1994) Cosmic dust: terrestrial accretion rate and solubility in seawater. Min. Mag. 58A, 718-719.

1. Reconstructing the Os-isotope Record of Seawater
2. Isotope Topology of the Mantle
3. Partitioning of Os between Mineral Phases in Mantle-derived Rocks
5. Anthropogenic PGE Pollution of Coastal Environments
6. Continental Weathering and Runoff of Osmium