DOI: 10.1016/j.gloplacha.2013.05.004
论文题名: Paleomagnetism and biostratigraphy of sediments from Southern Ocean ODP Site 744 (southern Kerguelen Plateau): Implications for early-to-middle Miocene climate in Antarctica
作者: Florindo F. ; Farmer R.K. ; Harwood D.M. ; Cody R.D. ; Levy R. ; Bohaty S.M. ; Carter L. ; Winkler A.
刊名: Global and Planetary Change
ISSN: 0921-8226
出版年: 2013
卷: 110 起始页码: 434
结束页码: 454
语种: 英语
英文关键词: Antarctica
; CONOP
; Diatom biostratigraphy
; Kerguelen Plateau
; Miocene
; Paleoclimate
; Paleomagnetism
Scopus关键词: Antarctica
; CONOP
; Kerguelen plateau
; Miocene
; Paleoclimates
; Paleomagnetism
; Constrained optimization
; Geomagnetism
; Glaciers
; Isotopes
; Ocean currents
; Sediments
; Biostratigraphy
; biostratigraphy
; chronostratigraphy
; geoaccumulation
; geomagnetic field
; ice sheet
; ice shelf
; microfossil
; Miocene
; paleoecology
; paleoenvironment
; paleomagnetism
; sediment analysis
; sedimentation
; Antarctic Circumpolar Current
; Indian Ocean
; Kerguelen Plateau
; Southern Ocean
; Bacillariophyta
英文摘要: New paleomagnetic results from lower-to-middle Miocene samples from Ocean Drilling Program (ODP) Holes 744A and 744B, cored during ODP Leg 119 on the southern Kerguelen Plateau (Indian Ocean sector; Southern Ocean), provide a chronostratigraphic framework for an existing and under-utilized paleoclimate archive during a key period of Antarctic climate and ice sheet evolution. Site 744 is strategically positioned for high-latitude paleoceanographic and paleoclimatic studies because it lies within the southern domain of the Antarctic Circumpolar Current (ACC) and in proximity to the large and active Lambert Glacier-Amery Ice Shelf drainage system of the East Antarctic Ice Sheet. Magnetostratigraphic results were reported previously for this site, but technical difficulties and limited sampling prevented confident correlation of the magnetic polarity record with the geomagnetic polarity timescale. Our results, which are constrained by new semi-quantitative analyses of diatom assemblages and radiolarian first and last appearance events that are evaluated within a regional Southern Ocean biostratigraphic dataset through Constrained Optimization (CONOP) model runs, permit significant refinement of previous age models for the lower-to-middle Miocene sequence recovered at Site 744 (spanning the interval from ~. 21 to 13.7. Ma). An extended record of sediment accumulation, with average sedimentation rates of ~. 0.7-0.9. cm/kyr, is interrupted by a series of hiatuses in the middle Miocene. These disruptions in sediment supply, or erosional events, could mark a local response of north-south fluctuations in the location and/or strength of the Antarctic Circumpolar Current during transient glacial events within the Mid-Miocene Climate Optimum (MMCO; ~. 17 to 14.45. Ma). With the enhanced age control provided by this study, combined with a refined chronostratigraphy for the underlying upper Eocene to Oligocene strata, Site 744 becomes a good candidate for future high-resolution stable isotope and microfossil paleoecological work, which will further elucidate the late Paleogene and early Neogene paleoenvironmental history of the Southern Ocean. © 2013 Elsevier B.V. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84888840029&doi=10.1016%2fj.gloplacha.2013.05.004&partnerID=40&md5=1ab24579f81ad4b3511c77ace4db9c24
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/11132
Appears in Collections: 全球变化的国际研究计划
There are no files associated with this item.
作者单位: Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata, 605, I-00143 Rome, Italy
Recommended Citation:
Florindo F.,Farmer R.K.,Harwood D.M.,et al. Paleomagnetism and biostratigraphy of sediments from Southern Ocean ODP Site 744 (southern Kerguelen Plateau): Implications for early-to-middle Miocene climate in Antarctica[J]. Global and Planetary Change,2013-01-01,110.