Department of Geology and Geophysics, Indian Institute of Technology, Kharagpur 721 302, India.
J Biosci. 2009 Nov;34(5):749-64. doi: 10.1007/s12038-009-0066-7.
Deep-sea benthic foraminifera, planktic foraminifer Globigerina bulloides and pteropods have been quantitatively analysed in 451 samples from Ocean Drilling Program (ODP) Hole 716A, to understand both surface and deep-sea palaeoceanographic changes in the equatorial Indian Ocean basin during the late Quaternary (approximately 444-151 Kyrs). Benthic foraminifera were analysed from >125 microm size fraction whereas Globigerina bulloides and pteropods were analysed from > 150 microm size fraction. Factor analysis of most dominant benthic foraminiferal species over the studied time span made it possible to identify three biofacies characterizing distinct deep-sea environmental settings at Hole 716A. The environmental interpretation of each species is based on the ecology of recent deep-sea benthic foraminifera. The faunal record indicates fluctuating deep-sea conditions including changes in surface productivity, organic food supply and deep-sea oxygenation linked to changing wind intensities. These changes are pronounced on glacial-interglacial time scales driven by summer monsoon winds.
对取自大洋钻探计划(ODP)716A 孔的 451 个样本中的深海底栖有孔虫、浮游有孔虫Globigerina bulloides 和翼足类进行了定量分析,以了解晚第四纪(约 444-151 千年前)期间赤道印度洋盆地的表层和深海古海洋变化。底栖有孔虫分析采用>125 微米粒径部分,而 Globigerina bulloides 和翼足类则采用>150 微米粒径部分。对研究期间最主要的底栖有孔虫种进行的因子分析,使得有可能在 716A 孔识别出三种生物相,它们代表了不同的深海环境。对每个种的环境解释基于现代深海底栖有孔虫的生态学。动物群记录表明,深海条件波动较大,包括与季风强度变化有关的表层生产力、有机食物供应和深海氧化作用的变化。这些变化在夏季季风驱动的冰期-间冰期时间尺度上很明显。