Abstract
Bottom current deposits (contourites) form in association with modern-day or ancient oceanic gateways. A paucity of examples in the ancient record and the lack of consensus on diagnostic criteria for differentiating them from other deepwater deposits limit our understanding of how they may record past global oceanic circulation, tectonic events and gateway evolution. This work describes an exceptional example of Eocene to middle Miocene deep-marine deposits located both onshore and offshore deepwater environments around the island of Cyprus. Multidisciplinary approaches were used to discriminate contourite facies associations, propose a sedimentary model, and interpret the relations with regional tectonics and the evolution of the nearby Indian Gateway. Contourite deposits appear in late Eocene to middle Miocene intervals interstratified with pelagic/hemipelagic sediments, turbidites and mass-transport deposits (MTDs). These deepwater deposits developed along a slope basin located on the upper plate of an active margin, evolving from a wide basin formed during a period of tectonic quiescent into a series of shallowing-upward, segmented sub-basins affected by compressional stress. The present study proposes a sedimentary model in which two contourite depositional systems developed: first in the Eocene (dominated by finer-grained contourites), and then during the latest Oligocene to middle Miocene (dominated by coarser-grained contourites). Both systems were buried by extensive marl deposits and record the respective influence of deep (circulating NW) and intermediate (circulating SE) water masses. The long-term evolution of the contourites reflects tectonic events that enhanced subduction processes south of Cyprus as well as exchange between the Neotethys Ocean and the Indian and Atlantic Oceans —until the final closure of the Indian Gateway by the end of the middle Miocene, when a new circulation pattern was established with the formation of the Mediterranean Sea.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
