کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4748464 1360108 2012 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Gephyrocapsa occurrence during the Middle Pleistocene transition in the Northern Pacific Ocean (Shatsky Rise)
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فسیل شناسی
پیش نمایش صفحه اول مقاله
Gephyrocapsa occurrence during the Middle Pleistocene transition in the Northern Pacific Ocean (Shatsky Rise)
چکیده انگلیسی

The gephyrocapsids, main component of the Pleistocene calcareous nannofossil assemblages, are here discussed as biostratigraphical and paleoclimate tools. The occurrence of the genus Gephyrocapsa is quantitatively analysed in the core ODP 198-1209B, collected in the NW Pacific Ocean. The studied stratigraphic succession covers a time interval including the Middle Pleistocene Transition (MPT), a highly investigated period characterized by important global climate changes. During the Pleistocene, Gephyrocapsa is extremely abundant and provides several bioevents used in biostratigraphy. In addition to the known standard events, we observe the occurrence of particular Gephyrocapsa morphogroups and significant changes in the relative abundance of G. caribbeanica. In the Early-Middle Pleistocene we identify four intervals based on the Gephyrocapsa content. Moreover, during the MPT, the stratigraphic distribution of Gephyrocapsa underlines a dominance of both the small morphogroup and the medium-sized G. caribbeanica that could be dependent on their paleoecology. Small Gephyrocapsa and G. caribbeanica seem to be more competitive than other coccolithophores during the global oceanographic variations and the re-organisation of the glacial-interglacial periodicity during the MPT.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geobios - Volume 45, Issue 2, March–April 2012, Pages 209–217
نویسندگان
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