Calcareous Nannofossil Biostratigraphy and Growth Periods of Co-Rich Crusts from Pacific Seamounts
Zhang Haisheng
Han Zhengbing
Lei Jijiang
Zhao Jun
Yu Peisong
Hu Ji
Lu Bing
PulyaevaIA
Abstract：It enriches the geological history of Co-rich crusts (CRC)formation and the paleoceanography for us to understand the growth ages and periods of CRC.CRC samples collected from the Magellan and mid-Pacific seamounts were studied for the growth geological ages and periods by employing biostratigraphy (biological impressions).The primary formation geological ages and calcareous nannofossil assembly are different between CM3D06 CRC from the Magellan seamount and CB14 CRC from the mid-Pacific seamount.Based on the identification of calcareous nannofossil imprints and original fossil remains,five growth periods are determined for CM3D06 CRC,namely,Cretaceous (or older),Late Paleocene-Early Eocene,Middle-Late Eocene, Middle-Late Miocene,and Pliocene-Pleistocene,whereas four growth periods for CB14 CRC are determined as follows:Late Paleocene,Middle-Late Eocene,Middle Miocene,and Pliocene to Pleistocene.Regional characteristics for the nannofossil com-bination features of two CRC samples indicate the impact of oceanic environment on marine organisms and their adaptation.The unconformity of sub-layers and variation of structure and texture of the two CRC samples show that the main hiatus occurred during Oligocene.
Keywords：Co-rich crustcalcareous nannofossilbiostratigraphygeological agePacific seamountgeochemistry
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 775-783 )