摘要
正确判断富钴结壳生长年代及过程有助于研究结壳形成地质历史和重建古海洋环境.利用生物地层学方法(生物遗留印痕)对太平洋不同海山结壳样品进行生长时代和阶段研究,发现麦哲伦海山CM3D06结壳和中太平洋海山CB14结壳最初形成年代和富集特征差异显著:前者为白垩纪(或更古老)、晚古新世-早始新世、中-晚始新世、中-晚中新世、上新世-更新世等5个阶段;后者为晚古新世-早始新世、中-晚始新世、中中新世、上新世-更新世等4个阶段.两座海山结壳层内部超微化石组合具有极强的区域性特征,反映了大洋环境对生物的影响以及生物对环境的适应.结壳层间的不整合和结构构造的变化指示在渐新世其生长存在间断期,与成矿作用的间断有关.
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.
出处
《地球科学（中国地质大学学报）》
EI
CSCD
北大核心
2014年第7期775-783,共9页
Earth Science-Journal of China University of Geosciences
基金
国家自然科学基金(Nos.41076072,40676025)
