Minor changes in biomarker assemblages in the aftermath of the Cretaceous-Paleogene mass extinction event at the Agost distal section (Spain)

Variation in organic matter across the Cretaceous-Paleogene boundary in New Zealand supports the “Living Ocean” model of biotic recovery

“…Elsewhere at other distal sections, similar muted algal biomarker responses have been observed (Fig. 9D), such as Agost in Spain (Sosa-Montes de Oca et al, 2021), IODP Site 738 (Kerguelen Plateau) and Site 1262 (Walvis Ridge) (Bralower et al, 2020). In contrast, a transient decrease in S/(S + H) ratios in the neritic K-Pg boundary distal section from the Fish Clay in Denmark (Sepúlveda et al, 2009) was observed (Fig.…”

“…10B and C). This was also observed in the δ 13 C TOC record of the Agost distal section (Spain) (Sepúlveda et al, 2019;Sosa-Montes de Oca et al, 2021). We attribute this discrepancy to the complex organic matter source changes across the K-Pg boundary.…”

“…There have been several biomarker studies on the biotic response and recovery after the K-Pg boundary in distal sections (Bralower et al, 2020;Sepúlveda et al, 2009;Taylor et al, 2018;Sosa-Montes de Oca et al, 2021), as well as recent papers on the biotic response within the Chicxulub structure (Schaefer et al, 2020). The findings of these studies differ, however, the response of non-fossilizing plankton appears to be spatially variable.…”

“…Sepúlveda et al (2009) used sterane distributions to argue for blooms of algae just above the boundary in the Fish Clay of Denmark (Stevns Klint distal section), and then a rapid recovery to preevent distributions. Sosa-Montes de Oca et al (2021) used the distribution of specific phytoplankton (pristane, phytane, steranes), vascular plant (n-alkanes) and bacterial (hopanes) biomarkers at the Agost distal section (Spain) to reveal highly variable terrigenous inputs immediately preceding and right after K-Pg boundary but minimal changes in the algal and bacterial assemblages. Similarly, Bralower et al (2020) analysed the micrite-rich layer (boundary clay) at 31 sites across the world, to argue for transient ocean-wide blooms of cyanobacteria and algae in the millennia after the K-Pg boundary impact event.…”

Lethal microbial blooms delayed freshwater ecosystem recovery following the end-Permian extinction

“… 59 . Data sources: late early Cambrian (c. 509 Ma) 63 , 85 , 86 ; end-Ordovician (c. 445 Ma) 63 , 87 ; Lau Event (c. 424 Ma) 64 ; Late Devonian (c. 372 Ma) 62 , 63 ; Hangenberg Event (c. 359 Ma) 62 , 63 ; end-Guadalupian (c. 260 Ma) 19 , 88 ; end-Permian (c. 252 Ma) 10 , 16 , 37 , 44 , 47 , 49 – 54 , 63 , 89 ; end-Triassic (c. 183 Ma) 60 , 64 , 90 – 92 ; Toarcian oceanic anoxic event (c. 183 Ma) 93 – 95 ; Cretaceous OAE 1a (c. 123 Ma) 96 ; Cretaceous OAE 2 (c. 94 Ma) 96 – 102 ; end-Cretaceous (c. 66 Ma) 62 , 63 , 69 , 70 , 103 – 105 ; Paleocene-Eocene Thermal Maximum (c. 56 Ma) 61 , 106 – 109 ; Holocene 1 , 2 , 110 , 111 . Ed.…”