Sediment sorting and focusing in the eastern equatorial Pacific

被引:11
作者
Bista, Diksha [1 ,2 ]
Kienast, Stephanie S. [1 ]
Hill, Paul S. [1 ]
Kienast, Markus [1 ]
机构
[1] Dalhousie Univ, Dept Oceanog, 1355 Oxford St,POB 15000, Halifax, NS B3H 4R2, Canada
[2] Univ Bristol, Sch Geog Sci, Bristol, Avon, England
基金
加拿大创新基金会; 加拿大自然科学与工程研究理事会;
关键词
Grain size; Sediment focusing; Sorting coefficient; Particle sorting; Eastern equatorial Pacific; GRAINED UNFLOCCULATED SEDIMENTS; PANAMA BASIN; SIZE CHARACTERISTICS; SEA-FLOOR; TH-230; ATLANTIC; REDISTRIBUTION; OCEAN; ACCUMULATION; PRODUCTIVITY;
D O I
10.1016/j.margeo.2016.09.016
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
The interpretation of sedimentary records in terms of glacial-interglacial changes in particle flux in the eastern equatorial Pacific (EEP) has been controversial. Here, we analyze disaggregated inorganic grain size (DIGS) distributions of three marine sediment cores from this region, focusing on the last 21 ka, to investigate evidence of sediment redistribution on the sea floor. Grain size sorting coefficients show that sediments in the EEP are moderately to well sorted, indicating sediment reworking in this, region due to bottom currents. Furthermore, a systematic correlation between focusing factors and sorting coefficients at two sites shows that more focused sediments are also better sorted. We conclude that grain size based sedimentary records are consistent with the Th-230-based evidence of lateral sediment redistribution on the sea floor in the EEP. (C) 2016 Elsevier B.V. All rights reserved.
引用
收藏
页码:151 / 161
页数:11
相关论文
共 80 条
[1]   Modern CaCO3 preservation in equatorial Pacific sediments in the context of late-Pleistocene glacial cycles [J].
Anderson, R. F. ;
Fleisher, M. Q. ;
Lao, Y. ;
Winckler, G. .
MARINE CHEMISTRY, 2008, 111 (1-2) :30-46
[2]  
Anderson R.F., 2005, PALEOCEANOGRAPHY, V20, P381
[3]   A comparison of multiple proxies for export production in the equatorial Pacific [J].
Averyt, KB ;
Paytan, A .
PALEOCEANOGRAPHY, 2004, 19 (04) :1-14
[4]   DISTRIBUTION OF THORIUM ISOTOPES BETWEEN DISSOLVED AND PARTICULATE FORMS IN THE DEEP-SEA [J].
BACON, MP ;
ANDERSON, RF .
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 1982, 87 (NC3) :2045-2056
[5]  
BACON MP, 1984, ISOT GEOSCI, V2, P97
[6]  
Bista D., 2015, THESIS
[7]   GRADISTAT: A grain size distribution and statistics package for the analysis of unconsolidated sediments [J].
Blott, SJ ;
Pye, K .
EARTH SURFACE PROCESSES AND LANDFORMS, 2001, 26 (11) :1237-1248
[8]   Partitioning of eolian and hemipelagic sediment in eastern equatorial Pacific core TR 163-31B and the late Quaternary paleoclimate of the northern Andes [J].
Boven, KL ;
Rea, DK .
JOURNAL OF SEDIMENTARY RESEARCH, 1998, 68 (05) :850-855
[9]   Excess sediment 230Th:: Transport along the sea floor or enhanced water column scavenging? [J].
Broecker, Wallace .
GLOBAL BIOGEOCHEMICAL CYCLES, 2008, 22 (01)
[10]   Eastern Equatorial Pacific productivity and related-CO2 changes since the last glacial period [J].
Calvo, Eva ;
Pelejero, Carles ;
Pena, Leopoldo D. ;
Cacho, Isabel ;
Logan, Graham A. .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2011, 108 (14) :5537-5541