Bostwick J.A. et al. (1995) Asteroid sample return mission II: Eltanin recovered (abs. Meteoritics 30, 490 ):
The Late Pliocene impact of the Eltanin asteroid produced a truly unique deposit in the known sedimentary record. It is the only known impact into a deep-ocean basin. Evidence of this impact was first discovered as an Ir anomaly in sediments from core El 3-3 recovered by the USNS Eltanin in 1964. Further examination of these sediments revealed that Ir was largely contained (ca. 50%) within mm-sized grains of vesicular impact melt and that several % of the impact debris consists of unmelted meteorite fragments. The unmelted fragments are from a meteoritic basalt similar to howardites and mesosiderites and have been named the Eltanin meteorite. Trace components of the impact debris include rare metal grains and glassy spherules containing megnesioferrite spinel. The spherules may be impact vapor condensates. Thus the impact debris contains materials derived from the unaltered projectile, an impact melt (a simple mixture of projectile and salts from the seawater target), and an impact vapor cloud. Assuming that the impact site was near core El 3-4 (57° 47.2' S and 90° 47.6' W), the site with the most debris, a conservative estimate of the minimum asteroid diameter was about 500 m, although it could have been as large as 2 km. ______________________________________________ Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
