| Abstract |
Permian to Jurassic bedded chert sequences in the Japanese accretionary complexes are recognized as pelagic deep-sea deposits and characterized by a very low sedimentation rate (less than a few millimeters per thousand years) and absence of coarse-grained terrigenous clastics. Owing to their low sedimentation rate and long-term continuous deposition, these bedded cherts could provide the accretion history of extraterrestrial matter over geologic time. In this talk, I will review studies of extraterrestrial matter in bedded chert sequences from the Jurassic accretionary complexes, southwest Japan. The following topics will be presented and discussed in the seminar:
(1) The origin and significance of fossil micrometeorites found in the Triassic and Jurassic bedded cherts;
(2) collapse of marine ecosystem triggered by a Late Triassic impact event. |
