Increased Marine Productivity in the Southern Humboldt Current System During MIS 2–4 and 10–11

Tapia, Raúl; Ho, Sze Ling; Nunez-Ricardo, Samuel; Marchant, Margarita; Lamy, Frank; Hebbeln, Dierk

doi:10.1029/2020pa004066

Cited by 6 publications

(3 citation statements)

References 109 publications

(177 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This expansion could result in a higher sensitivity of the outer PIS to abrupt temperature changes and thus initiate a higher susceptibility to millennial-scale variations as recorded here in freshwater runoff and linked terrigenous sediment deposition. Such an assumption is in line with the study by Tapia et al ( 36 ) where the high nutrient inflow during MIS 2–4 is considered to be derived from increased precipitation combined with a more active ice sheet. Furthermore, the onset of the TIPs during late MIS 3, when temperature levels were warmer and eustatic sea level higher than during MIS 4 and MIS 2, indicates that increasing precipitation associated with a northward movement of the SWW/ACC system plays an important role.…”

Section: Millennial-scale Pis Variationssupporting

confidence: 85%

See 1 more Smart Citation

A marine record of Patagonian ice sheet changes over the past 140,000 years

Hagemann,

Lamy,

Arz

et al. 2024

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

Terrestrial glacial records from the Patagonian Andes and New Zealand Alps document quasi-synchronous Southern Hemisphere–wide glacier advances during the late Quaternary. However, these records are inherently incomplete. Here, we provide a continuous marine record of western–central Patagonian ice sheet (PIS) extent over a complete glacial–interglacial cycle back into the penultimate glacial (~140 ka). Sediment core MR16-09 PC03, located at 46°S and ~150 km offshore Chile, received high terrestrial sediment and meltwater input when the central PIS extended westward. We use biomarkers, foraminiferal oxygen isotopes, and major elemental data to reconstruct terrestrial sediment and freshwater input related to PIS variations. Our sediment record documents three intervals of general PIS marginal fluctuations, during Marine Isotope Stage (MIS) 6 (140 to 135 ka), MIS 4 (~70 to 60 ka), and late MIS 3 to MIS 2 (~40 to 18 ka). These higher terrigenous input intervals occurred during sea-level low stands, when the western PIS covered most of the Chilean fjords, which today retain glaciofluvial sediments. During these intervals, high-amplitude phases of enhanced sediment supply occur at millennial timescales, reflecting increased ice discharge most likely due to a growing PIS. We assign the late MIS 3 to MIS 2 phases and, by inference, older advances to Antarctic cold stages. We conclude that the increased sediment/meltwater release during Southern Hemisphere millennial-scale cold phases was likely related to higher precipitation caused by enhanced westerly winds at the northwestern margin of the PIS. Our records complement terrestrial archives and provide evidence for PIS climate sensitivity.

show abstract

Section: Millennial-scale Pis Variationssupporting

confidence: 85%

“…Thus, they are restricted to the continental margin north of the PIS off central Chile (ODP Site 1234; e.g., refs. 33 and 34 ) and further offshore in the southern section of the southeast Pacific [GeoB3327-5 and PS75/034-2; ( 35 , 36 )], locations which are only partially within the range of terrigenous sediment input from South America ( Fig. 1 ).…”

mentioning

confidence: 99%

A marine record of Patagonian ice sheet changes over the past 140,000 years

Hagemann,

Lamy,

Arz

et al. 2024

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

View full text Add to dashboard Cite

show abstract

“…with the factor 8.333 representing the molecular weight ratio of CaCO 3 and carbon (e.g., Faust et al, 2020;Tapia et al, 2021).…”

Section: Core Metadatamentioning

confidence: 99%

The Importance of Ecological Accommodation Space and Sediment Supply for Cold-Water Coral Mound Formation, a Case Study From the Western Mediterranean Sea

et al. 2021

Self Cite

View full text Add to dashboard Cite

The formation of cold-water coral (CWC) mounds is commonly seen as being the result of the sustained growth of framework-forming CWCs and the concurrent supply and deposition of terrigenous sediments under energetic hydrodynamic conditions. Yet only a limited number of studies investigated the complex interplay of the various hydrodynamic, sedimentological and biological processes involved in mound formation, which, however, focused on the environmental conditions promoting coral growth. Therefore, we are still lacking an in-depth understanding of the processes allowing the on-mound deposition of hemipelagic sediments, which contribute to two thirds of coral mound deposits. To investigate these processes over geological time and to evaluate their contribution to coral mound formation, we reconstructed changes in sediment transport and deposition by comparing sedimentological parameters (grain-size distribution, sediment composition, accumulation rates) of two sediment cores collected from a Mediterranean coral mound and the adjacent seafloor (off-mound). Our results showed that under a turbulent hydrodynamic regime promoting coral growth during the Early Holocene, the deposition of fine siliciclastic sediments shifted from the open seafloor to the coral mounds. This led to a high average mound aggradation rate of >130 cm kyr–1, while sedimentation rates in the adjacent off-mound area at the same time did not exceed 10 cm kyr–1. Thereby, the baffling of suspended sediments by the coral framework and their deposition within the ecological accommodation space provided by the corals seem to be key processes for mound formation. Although, it is commonly accepted that these processes play important roles in various sedimentary environments, our study provided for the first time, core-based empirical data proving the efficiency of these processes in coral mound environment. In addition, our approach to compare the grain-size distribution of the siliciclastic sediments deposited concurrently on a coral mound and on the adjacent seafloor allowed us to investigate the integrated influence of coral mound morphology and coral framework on the mound formation process. Based on these results, this study provides the first conceptual model for coral mound formation by applying sequence stratigraphic concepts, which highlights the interplay of the coral-framework baffling capacity, coral-derived ecological accommodation space and sediment supply.

show abstract

Composition, age and origin of Pleistocene turbidite deposits at ODP site 1232, Nazca plate: Implications for volcanism and climate change in central south Chile

Beck

Hickey‐Vargas

2022

Journal of South American Earth Sciences

View full text Add to dashboard Cite

Increased Marine Productivity in the Southern Humboldt Current System During MIS 2–4 and 10–11

Cited by 6 publications

References 109 publications

A marine record of Patagonian ice sheet changes over the past 140,000 years

A marine record of Patagonian ice sheet changes over the past 140,000 years

The Importance of Ecological Accommodation Space and Sediment Supply for Cold-Water Coral Mound Formation, a Case Study From the Western Mediterranean Sea

Composition, age and origin of Pleistocene turbidite deposits at ODP site 1232, Nazca plate: Implications for volcanism and climate change in central south Chile

Contact Info

Product

Resources

About