Early history of the Western Pacific Warm Pool during the middle to late Miocene (similar to 13.2-5.8 Ma): Role of sea-level change and implications for equatorial circulation
Nathan, SA; Leckie, RM; mleckie@geo.umass.edu
2009
发表期刊PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
ISSN0031-0182
卷号274期号:40606页码:140-159
摘要We document the waxing and waning of a "proto-warm pool" in the western equatorial Pacific (WEP) based on a study of multi-species planktic foraminiferal isotope ratios and census data spanning the 13.2-5.8 Ma interval at ODP Site 806. We hypothesize that the presence or absence of a proto-warm pool in the WEP, caused by the progressive tectonic constriction of the Indonesian Seaway and modulated by sea level fluctuations, created El Nino/La Nina-like alternations of hydrographic conditions across the equatorial Pacific during the late Miocene. This hypothesis is supported by the general antithetical relationship observed between carbonate productivity and preservation in the western and eastern equatorial Pacific, which we propose is caused by these alternating ocean-climate states. Warming of thermocline and surface waters, as well as a major change in planktic foraminferal assemblages record a two-step phase of proto-warm pool development similar to 11.6-10 Ma, which coincides with Miocene isotope events Mi5 and Mi6, and sea-level low stands. We suggest that these changes in the biota and structure of the upper water column in the WEP mark the initiation of a more modern equatorial current system, including the development of the Equatorial Undercurrent (EUC), as La Nina-like conditions became established across the tropical Pacific. This situation sustained carbonate and silica productivity in the eastern equatorial Pacific (EEP) at a time when carbonate preservation sharply declined in the Caribbean. Proto-warm pool weakening after similar to 10 Ma may have contributed to the nadir of a similar "carbonate crash" in the EEP. Cooling of the thermocline and increased abundances of thermocline taxa herald the decay of the proto-warm pool and higher productivity in the WEP, particularly similar to 9.0-8.8 Ma coincident with a major perturbation in tropical nannofossil assemblages. We suggest that this interval of increased productivity records El Nino-like conditions across the tropical Pacific and the initial phase of the widespread "biogenic bloom". Resurgence of a later proto-warm pool in the WEP similar to 6.5-6.1 Ma may have spurred renewed La Nina-like conditions, which contributed to a strong late phase of the "biogenic bloom" in the EEP. (C) 2009 Elsevier B.V. All rights reserved.
部门归属[Nathan, Stephen A.; Leckie, R. Mark] Univ Massachusetts, Dept Geosci, Amherst, MA 01003 USA
关键词Western Pacific Warm Pool Carbonate Crash Biogenic Bloom Equatorial Pacific Indonesian Seaway Planktic Foraminiferal Isotope Paleoecology Middle To Late Miocene Mi Events Sea Level Ocean Circulation Central American Seaway
学科领域Geography, Physical ; Geosciences, Multidisciplinary ; Paleontology
URL查看原文
收录类别sci
文献类型期刊论文
条目标识符http://ir.scsio.ac.cn/handle/344004/8417
专题海洋科技动态信息-印太暖池系统研究
通讯作者mleckie@geo.umass.edu
推荐引用方式
GB/T 7714
Nathan, SA,Leckie, RM,mleckie@geo.umass.edu. Early history of the Western Pacific Warm Pool during the middle to late Miocene (similar to 13.2-5.8 Ma): Role of sea-level change and implications for equatorial circulation[J]. PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,2009,274(40606):140-159.
APA Nathan, SA,Leckie, RM,&mleckie@geo.umass.edu.(2009).Early history of the Western Pacific Warm Pool during the middle to late Miocene (similar to 13.2-5.8 Ma): Role of sea-level change and implications for equatorial circulation.PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY,274(40606),140-159.
MLA Nathan, SA,et al."Early history of the Western Pacific Warm Pool during the middle to late Miocene (similar to 13.2-5.8 Ma): Role of sea-level change and implications for equatorial circulation".PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY 274.40606(2009):140-159.
条目包含的文件
文件名称/大小 文献类型 版本类型 开放类型 使用许可
Early history of the(4437KB) 开放获取--请求全文
个性服务
推荐该条目
保存到收藏夹
查看访问统计
导出为Endnote文件
相关权益政策
暂无数据
收藏/分享
所有评论 (0)
暂无评论
 

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。