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Twenty-two peat samples collected at different depths of a core including the layer affected by the 1908 explosion in Tunguska area of Central Siberia, Russia, and three basalt samples collected near the site, are analyzed by ICP-MS. The concentrations of Pd, Ni, Co, E REE, Ti and Sr in the event layers are 4-35 times higher than the background values in the normal layers. The variation of Pd is closely related to Ni, Co and ΣREE in the event layers, but not to these elements in the normal layers. It indicates that these excess elements came from the same source, i.e. the Tunguska explosion body. In addition, the patterns of Cl-chondrite-normalized REE in the event layers ((La/Yb)N≈2-3) are much flatter than those in the normal layers ((La/Yb)N≈7-143), and differ from those in the three basalt samples. The concentrations of REE in the three basalt samples are tens times higher than those in the event layers. It may be inferred that these excess elements could not be produced by the contamination of th
Twenty-two peat samples collected at different depths of a core including the layer affected by the 1908 explosion in Tunguska area of Central Siberia, Russia, and three basalt samples collected near the site were analyzed by ICP-MS. The concentrations of Pd, Ni, Co, E REE, Ti and Sr in the event layers are 4-35 times higher than the background values in the normal layers. The variation of Pd is closely related to Ni, Co and ΣREE in the event layers, but not to In addition, the patterns of Cl-chondrite-normalized REE in the event layers ((La / Yb) N≈2 -3) are much flatter than those in the normal layers ((La / Yb) N≈7-143), and differ from those in the three basalt samples. The concentrations of REE in the three basalt samples are tens times higher than that in the event layers. It may be inferred that these excess elements could not be produced by th e contamination of th