Original Research ARTICLE
Sediment provenance of the Nansha Trough since 40ka B.P. in the South China Sea: Evidence from δ13Corg, TOC and pollen composition
- 1South China Sea Institute of Oceanology (CAS), China
Geochemical proxies in organic matter (OM) are considered to be reliable proxies for deciphering types of paleo-vegetation (C3 plants and C4 plants) and their abundance. The contributions of total organic carbon (TOC), stable carbon isotopes (δ13Corg), total nitrogen (TN) and organic carbon to total nitrogen ratios (C/N) were obtained from a gravity core NS07-25 (6°39.945′ N, 113°32.936′ E, water depth 2006 m), extracted from the southern South China Sea (SCS). These data were used to reconstruct the climate changes of the Nansha Trough since 40ka B.P. by comparing them with pollen data from the same core, and this comparison provides better sediment provenance details in the study area. During the periods between 37ka to 27ka, and from 12.5ka to modern day, the majority of terrestrial sediment received from Borneo, and some climatic events have been governed by aeolian fluxes from mid-latitude areas (mainland China). These periods were relatively humid, compared to 27ka to 12.5ka, where the majority of terrestrial sediment came from the Sunda Shelf through riverine pathways. This study serves as the first study to correlate deep oceanic pollen and geochemical proxies in order to identify the weaken terrestrial OM signals in the deep ocean.
Keywords: Southern South China Sea, TOC, δ13Corg, Pollen, Deep ocean, sediment provenance
Received: 13 Mar 2019;
Accepted: 29 Apr 2019.
Edited by:Giancarlo Scardia, São Paulo State University, Brazil
Reviewed by:Li Wu, Anhui Normal University, China
Mingrui Qiang, South China Normal University, China
Copyright: © 2019 Thilakanayaka, Chuanxiu, Xiang, Devendra and Dasanayaka. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Luo Chuanxiu, South China Sea Institute of Oceanology (CAS), Guangzhou, 510301, Guangdong Province, China, firstname.lastname@example.org