AUTHOR=Zhang Handan , Che Hong , Xia Jinqi , Cheng Qi , Qi Di , Cao Junqian , Luo Yiming 

TITLE=Sedimentary CaCO3 Accumulation in the Deep West Pacific Ocean

JOURNAL=Frontiers in Earth Science

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/earth-science/articles/10.3389/feart.2022.857260

DOI=10.3389/feart.2022.857260

ISSN=2296-6463

ABSTRACT=<p>Distribution of calcium carbonate (CaCO<sub>3</sub>) in marine sediment has been studied over the last century, and influence by multiple factors with regard to dissolution and dilution of sedimentary CaCO<sub>3</sub> has long been established. There is still lack of quantification on the influence of those factors, so it remains elusive to determine which specific process is driving the down-core variation of CaCO<sub>3</sub> content (<sub>wt</sub>CaCO<sub>3</sub>%) records. Here, based on a newly compiled CaCO<sub>3</sub> data set and a carbonate model, depth-profiles of sedimentary <sub>wt</sub>CaCO<sub>3</sub>% from the West Pacific Ocean can be well illustrated, and influence from different factors on their distribution features can be quantified. The deep ocean circulation is found to largely shape the inter-basin disparity in sedimentary <sub>wt</sub>CaCO<sub>3</sub>% distribution between the equatorial regions (e.g., the Western Equatorial Pacific Ocean and the Central Pacific Ocean) and the north–west regions (the Philippine Sea and the Northwest Pacific Ocean) in our study region. Moreover, the slow carbonate dissolution rate in the deep Central Pacific Ocean guarantees better accumulation of CaCO<sub>3</sub> at depth compared to that in other regions. However, enhanced dilution by non-carbonate materials of sedimentary CaCO<sub>3</sub> on a topographic complex can potentially obstruct the dissolution profiles constituted by sedimentary <sub>wt</sub>CaCO<sub>3</sub>% in the pelagic ocean. The aforementioned assertion suggests that changes of <sub>wt</sub>CaCO<sub>3</sub>% accumulation in marine sediment in the West Pacific Ocean can be used to dictate past changes of the deep ocean circulation (2,500 to 3,000 m) in this area but constraint on the non-carbonate flux, especially on the topographic complex, should be necessary.</p>