Origin, transportation and emplacement of Permian and Triassic exotic limestone blocks based on faunal analysis of foraminifers

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Limestone blocks contained in the Permian to Early Cretaceous accretionary complexes of Japan yield various kinds of Permian and Triassic foraminifers that provide restrictions considering the plate movement of the Panthalassan-originated seamounts, and tectonics and paleobiogeography of Paleozoic to Mesozoic in East Asia. This research program was performed to understand the field occurrences, lithologic properties, and fossil assemblages in confined and representative limestone blocks of each of the accretionary terranes of Japan that are most suitable for studying time- and space-distribution of Paleozoic and Mesozoic foraminifers in the Circum-Pacific regions and also have useful geologic data for the present study. Biostratigraphic distribution, faunal composition, and taxonomic diversity of foraminifers in relation to limestone lithologies were clarified in many of these limestone blocks. This research program discussed and revealed on paleobiogeography of Late Paleozoic foraminifers, depositional site of limestone and limestone-bearing strata, and post-depositional tectonic modification based on the careful examination of phylogenetic relationships, time- and space-distribution, degree of similarities of diagnostic species and faunal composition of these foraminifers, adding results of many unpublished data and literature survey to those obtained in this research program. Further time and information are necessary to lead the final conclusion to explain the aim of this program that is focused on the origin, transportation and emplacement of these exotic limestone blocks. Eighteen papers and many lines of new information deeply related to the aim of this program were obtained in these three years as the results of active promotion of this research program that was placed as the extension and further development of my serial work concerning evolution and paleobiogeography of Late Paleozoic and Mesozoic foraminifers.