Abstract
Volcanic atolls host exceptionally important marine ecosystems in the modern oceans. Yet, due to limited exposures, fossil atolls are poorly constrained. Multiple drowned Cretaceous volcanic atolls have been reported in the Pacific, but less information exists regarding those in the Tethys. Here we report on two early Cenomanian age volcanic atolls outcropping in Mt. Carmel (northern Israel), along the eastern Levant margin. These atolls are a few kilometers in diameter and differ significantly in facies from their surroundings, which are dominated by chalky calcareous mudstone and wackestone. The atolls are composed of grainstone, floatstone, rudstone and bafflestone facies, which are dominated by molluscans, notably gastropods, rudists, oysters and other bivalves. Corals and green algae are absent throughout these atolls. The studied sections of these atolls display a full succession, beginning with aggradation and ending with drowning. Age constraints for the volcanic phases suggest that deposition occurred within a relatively short time interval (<1 Myr) and the sequence represents a keep-up to give-up transition, within rising global and local sea-level trends. The inability of these atolls to keep up with rising sea level is attributed here to a suppressed carbonate factory, either due to drowning, turbidity and/or nutrient excess. Our study sheds new light on the dynamics of carbonate buildups during the Late Cretaceous and their ability to persist.
Original language | English |
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Article number | 105805 |
Journal | Sedimentary Geology |
Volume | 411 |
DOIs | |
State | Published - Jan 2021 |
Bibliographical note
Funding Information:This study was funded by Delek Drilling LP and by Ratio Oil Exploration under a research funding agreement with the University of Haifa. The authors would like to thank the National Nature and Parks Authority for permission to access and sample the study sites. Prof. Chaim Benajmini from Ben-Gurion University of the Negev (BGU) is thanked for useful discussions. Information on the benthic Foraminifera Orbitolina was provided by Helena Krasnova as part of her master thesis under the supervision of Prof. Benjamini at BGU. A special thanks to Ian Jarvis for sharing his raw data used to produce the carbon isotope curve. Two anonymous reviewers are acknowledged for their advice and remarks which contributed to improve the initial draft. The first author would like to personally thank Naama Sarid, Omry Nachum, Hadar Elyashiv and the Carmel-Galilee search and rescue unit for life-saving evacuation following a rock fall event in one of the research sites.
Funding Information:
This study was funded by Delek Drilling LP and by Ratio Oil Exploration under a research funding agreement with the University of Haifa . The authors would like to thank the National Nature and Parks Authority for permission to access and sample the study sites. Prof. Chaim Benajmini from Ben-Gurion University of the Negev (BGU) is thanked for useful discussions. Information on the benthic Foraminifera Orbitolina was provided by Helena Krasnova as part of her master thesis under the supervision of Prof. Benjamini at BGU. A special thanks to Ian Jarvis for sharing his raw data used to produce the carbon isotope curve. Two anonymous reviewers are acknowledged for their advice and remarks which contributed to improve the initial draft.
Publisher Copyright:
© 2020 Elsevier B.V.
Keywords
- Atoll succession
- Cretaceous
- Drowning
- Levant
- Rudists
ASJC Scopus subject areas
- Geology
- Stratigraphy