Abstract
Periplatform carbonate ooze records a composite signal reflecting both the regional oceanographic state and the development of the adjacent carbonate platform. Deconvolving these signals offers the possibility to obtain a holistic perspective on the factors governing the evolution of the platform, especially when the platform itself is not accessible. Here, we examine a case study from periplatform deposition in Site U1468 on the margins of the Kardiva Platform, Maldives. This site has a well-constrained record with seismic control of the geometric evolution of adjacent carbonate platforms. Here we integrate geochemistry, sedimentology and external constraints to address the relationship between local (platform evolution), regional (nutrient regime) and global (temperature, sea level) effects. The lower to middle Miocene succession at Site U1468 is comprised of a wackestone to packstone sequence that hosts foraminifera and other bioclastic grains, derived from neritic and pelagic sources, as well as biogenic siliceous material such as sponge spicules. The sequence records an increase in neritic supply to the periplatform from the late Burdigalian to the early Serravallian as recorded in Sr/Ca and δ13C values. The increase in neritic material coincided with a stepwise intensification of the regional Oxygen Minimum Zone (OMZ) recorded by Mn/Ca ratios. During these trends, short-lived oscillations in local carbonate production and OMZ intensity were superimposed on the larger trend. The expansion of the OMZ was driven by periods of cooling while the increase in neritic production was driven by warming and sea-level rise. These results reinforce existing models of the evolution of the Kardiva Platform with respect to sea level and add to it a refined understanding of the relation to regional nutrient patterns.
Original language | English |
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Article number | 109969 |
Journal | Palaeogeography, Palaeoclimatology, Palaeoecology |
Volume | 559 |
DOIs | |
State | Published - 1 Dec 2020 |
Bibliographical note
Funding Information:This work was partially funded by the German-Israel Foundation for Scientific Research and Development (GIF) 1-1336-301.8/2016 (MioEast project) awarded to NDW and CB. JR and CB want to thank the DFG for funding through the project INDOCARB (BE1272/23-1 and BE1272/23-1). JR thanks the MINECO of Spain for personal funding through the Juan de la Cierva Program and funding from research group RNM-190. The authors would like to thank editor-in-chief Thomas Algeo and guest editor Jeremy Young for their invaluable edits and comments as well as to Ángel Puga Bernabéu and an anonymous reviewer for their comments. Further thanks are extended to Dan Killam from the University of Arizona for his help improving the text. IODP are thanked for access to the samples and P.K. Swart for supplying the C and O isotope data. We thank Nimer Taha for assistance in the analytical measurements at the Basin Analysis and Petrophysical laboratory (PetroLab), University of Haifa. We would like to express our gratitude to the Mediterranean Sea Research Center of Israel (MERCI) for supporting Israel participation in IODP activities, including the participation of OMB as a member of Exp. 359.
Funding Information:
This work was partially funded by the German-Israel Foundation for Scientific Research and Development (GIF) 1-1336-301.8/2016 (MioEast project) awarded to NDW and CB. JR and CB want to thank the DFG for funding through the project INDOCARB ( BE1272/23-1 and BE1272/23-1 ). JR thanks the MINECO of Spain for personal funding through the Juan de la Cierva Program and funding from research group RNM-190. The authors would like to thank editor-in-chief Thomas Algeo and guest editor Jeremy Young for their invaluable edits and comments as well as to Ángel Puga Bernabéu and an anonymous reviewer for their comments. Further thanks are extended to Dan Killam from the University of Arizona for his help improving the text. IODP are thanked for access to the samples and P.K. Swart for supplying the C and O isotope data. We thank Nimer Taha for assistance in the analytical measurements at the Basin Analysis and Petrophysical laboratory (PetroLab), University of Haifa. We would like to express our gratitude to the Mediterranean Sea Research Center of Israel (MERCI) for supporting Israel participation in IODP activities, including the participation of OMB as a member of Exp. 359.
Publisher Copyright:
© 2020 Elsevier B.V.
Keywords
- Carbonate platforms
- IODP expedition 359
- Miocene Climatic Optimum
- Oxygen Minimum Zone
- Site U1468
ASJC Scopus subject areas
- Oceanography
- Ecology, Evolution, Behavior and Systematics
- Earth-Surface Processes
- Paleontology