气候变化领域集成服务门户(CCPortal): Controls on the abundance, provenance and age of organic carbon buried in continental margin sediments

CCPortal

DOI	10.1016/j.epsl.2021.116759
	Controls on the abundance, provenance and age of organic carbon buried in continental margin sediments
	Ausín B.; Bruni E.; Haghipour N.; Welte C.; Bernasconi S.M.; Eglinton T.I.
发表日期	2021
ISSN	0012821X
卷号	558
英文摘要	Continental margins play a fundamental role in the carbon cycle as primary oceanic locations of organic carbon (OC) burial. However, gaps remain in our understanding of factors controlling the distribution and preservation of organic matter (OM) in these heterogeneous and dynamic systems. In particular, the impact of hydrodynamic processes on the age, abundance, and stable isotopic composition of sedimentary OC is poorly constrained. Here, we characterize the OC present in bulk and grain-size sediment fractions from seven continental margin settings. Our results reveal that hydrodynamic particle sorting processes exert a ubiquitous influence on the radiocarbon age of OC. Both, hydrodynamic characteristics of mineral particles and the nature of their interactions with OM influence sedimentary OC content, whereas no significant influence of either effect is manifested in corresponding δ13C values. Since OC preferentially resides within the fine silt fraction (2-8 μm), and this fraction accounts for a substantial fraction of the bulk sediment mass, translocation and subsequent re-deposition of distant fine silt has the greatest potential to distort local OC signatures relative to those associated with clay or coarse silt fractions. We suggest that the magnitude of differences in 14C-age and OC content among grain-size fractions, determined by the interplay of hydrodynamic sorting and other site-specific processes, allow three different categories of depositional environment to be defined: initial, stable, and mature. Each domain is characterized by different degrees of vertical and lateral OC supply that reflect influences of local biological productivity and carbon export from overlying surface waters and physical forcing that drive hydrodynamic processes. This generic framework may serve as a guide to refine assessment of OC burial and to constrain the magnitude of potential aliasing among co-eval proxy signals in continental margin sedimentary sequences. © 2021 The Author(s)
关键词	continental margins grain size hydrodynamic sorting organic carbon radiocarbon age
英文关键词	Deposition; Grain size and shape; Hydrodynamics; Screening; Sedimentology; Sediments; Silt; Biological productivity; Depositional environment; Hydrodynamic characteristics; Hydrodynamic particles; Hydrodynamic process; Preservation of organic matters; Sedimentary sequence; Stable isotopic compositions; Organic carbon; continental margin; depositional environment; grain size; hydrodynamics; isotopic composition; marine sediment; organic carbon; organic matter; provenance; radiocarbon dating; sediment chemistry; sedimentary sequence; stable isotope; structural control
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203023
作者单位	Geological Institute, ETH Zurich, Switzerland; Geology Department, Salamanca University, Salamanca, Spain; Laboratory of Ion Beam Physics, ETH Zurich, Switzerland
推荐引用方式 GB/T 7714	Ausín B.,Bruni E.,Haghipour N.,et al. Controls on the abundance, provenance and age of organic carbon buried in continental margin sediments[J],2021,558.
APA	Ausín B.,Bruni E.,Haghipour N.,Welte C.,Bernasconi S.M.,&Eglinton T.I..(2021).Controls on the abundance, provenance and age of organic carbon buried in continental margin sediments.Earth and Planetary Science Letters,558.
MLA	Ausín B.,et al."Controls on the abundance, provenance and age of organic carbon buried in continental margin sediments".Earth and Planetary Science Letters 558(2021).