Vast laminated diatom mat deposits from the west low-latitude Pacific Ocean in the last glacial period

Trends and Future Projections for Marine Biogeochemistry Research in Indonesia (Tren dan Proyeksi Penelitian Biogeokimia Laut di Indonesia)

“…As reported by Bin et al (2009) who analyzed the diatom mats in Eastern Philippines Sea and identified the species of the diatoms as giant Ethmodiscus rex (Wallich) Hendey, blooms of which occurred during the last glacial periods. Diatoms were reported as the predominant contributors to global carbon fixation by accounting for over 40% of total oceanic primary production.…”

The silicon isotope composition of Ethmodiscus rex laminated diatom mats from the tropical West Pacific: Implications for silicate cycling during the Last Glacial Maximum

“…This model dates deposition of the DC and LDM-03 units to 31.0-29.4 kyr and 29.4-19.5 kyr, respectively (note that all reported ages are "before present") [Xiong et al, 2013a]. Unfortunately, the age model of core WPD-12 is not well established due to reversed accelerator mass spectrometry (AMS) 14 C age data throughout the core, and the age of the cored interval can be constrained only broadly to between~25 kyr and~19 kyr [Zhai et al, 2009]. Possible reasons for AMS 14 C age reversals in the study cores were considered by Xiong et al [2013a].…”

“…These characteristics suggest such a rapid increase in the EAWM during DC deposition that it triggered strong wind-driven upwelling [Xiong et al, 2010[Xiong et al, , 2013a and that upwelling then inhibited blooms of giant diatoms such as E. rex owing to their requirement for water mass stratification [Gingele and Schmieder, 2001;De Deckker and Gingele, 2002;Kemp and Villareal, 2013]. Wind-driven upwelling may have stimulated modest levels of small spring-bloom diatom productivity during DC deposition, as evidenced by an opal peak (Figure 4c), a maximum in small diatom abundance [Zhai et al, 2012], and high illite/smectite ratios (Figure 4d). [De La Rocha et al, 1998;Reynolds et al, 2008;Romero et al, 2011;Pichevin et al, 2012].…”

“…rex LDMs were deposited widely in the eastern Philippine Sea (EPS) during the Last Glacial Maximum (LGM) [ Xiong et al ., , and references therein], as documented in a series of cores recovered from the Parece Vela Basin (Figure ) during the 2003–2004 cruise of R/V Science No. 1 [ Zhai et al ., ]. The widespread occurrence of E .…”

“…The upper unit (0-286 cm; all depths are relative to the core top) is composed of olive-grey and grey, laminated diatom mats (LDM-03), which are dominated by fragmented valves of the mat-forming diatom E. rex in nearmonospecific assemblages ( Figure 3a) with extremely low abundances of other diatom species and radiolarians ( Figure 3b) [Zhai et al, 2009]. The middle unit (286-334 cm) is characterized by grey diatomaceous clays (DCs) that are dominated by E. rex and small spring-bloom diatoms [Zhai et al, 2012] but lack lamination. The lower unit (334-405 cm) comprises massive red pelagic clays (PCs) that generally lack a microfossil component.…”