Project

Discipline

Paleoceanography; Foraminifera; Environmental changes; Cold-water corals ecosystems; Bioindicators; Alboran-Cadiz system

Lead
Lay summary
The discovery of carbonate mounds and cold-water coral reef ecosystems (CCEs) along the European margin and in the Mediterranean Sea is a recent achievement. These discoveries have added new dimensions to the concept of carbonate factories and their importance in the geologic record. The scientific community identified the study of different micro/organism (such as foraminifera) in CCEs as a research challenge to better understand the formation of large CCEs, their biodiversity and their reaction to oceanographic and climate changes. In 2002 cold-water coral mounds were discovered in water depths of 500-600 m in the Gulf of Cadiz. The sediments contain alternating cold water coral-enriched and -depleted layers, showing striking similarities with the modern CCEs from the North Atlantic margin. Similar features discovered in the Alboran Sea (Western Mediterranean) opened a new research round of CCEs. Three SNSF projects granted to the proponent and focused on planktonic and benthic foraminifera provided the knowledge on modern assemblages to understand the dynamics of the fossil counterparts. It is now timely to investigate the foraminiferal fossil records of the CCEs to unravel their ecological importance in the past. We propose a high-resolution study of the ESF-EuroDiversity-MiCROSYSTEM Cores MD08-3227 and MD08-3216G recovered in the Gulf of Cadiz and spanning the upper 30 meters of sediments. We propose a cruise in the Alboran Sea to obtain a similar record. We will use quantitative data of benthic and planktonic foraminifera their isotopic signature and the chemistry of the sediments to intepret paleoenvironmental changes in the buried CCEs from the Gulf of Cadiz-Alboran Sea in the time frame provided by AMS14C dating and bio- and isotope- stratigraphy. The research will benefit of international collaboration (e.g., Royal Netherlands Institute for Sea Research (NIOZ) and Renard Centre of Marine Geology (RCMG)-Ghent), which provide complementary equipments and training of the PhD student on newly developed techniques. Our aim is to obtain a multiproxy paleoceanographic as follows: Reconstruction of the history of the western Mediterranean connection (Alboran-Cadiz system), CCE development in the last 150.000 years, and their relation to ecological, oceanographic and climate changes. Identification of regional and local factors determining similarities and differences between the Alboran Sea and the Gulf of Cadiz. Establishment of a causal link between CCE carbonate mounds and adjacent sediments. Testing the hypothesis of the Alboran-Cadiz gateway as an associated system also in recent times

Direct link to Lay Summary

Last update: 21.02.2013

Active participation

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The discovery of recent carbonate mounds and cold-water coral reef ecosystems (CCEs) along the European and African margins and in the Mediterranean Sea is a major achievement of the last decade. These discoveries have added a new dimension to the concept of carbonate factories and their widespread occurrence presents a challenge to understand their development and preservation and possible importance in the geologic record.Research of CCEs is still at an early stage and their role in the global carbon cycle is still poorly known. At several meetings (e.g., ESF-Magellan Workshops) the scientific community identified the study of different micro/organisms (such as foraminifera) in these coral geo-ecosystems as one of the most prominent research challenges to be addressed to better understand the formation of large CCEs, the maintenance of their biodiversity and their reaction to oceanographic and climate changes.In 2002 cold-water coral mounds were discovered in water depths of 500-600 m in the Gulf of Cadiz on the Pen Duick Escarpment. The sediments contain alternating cold water coral-enriched and -depleted layers, showing striking similarities with the modern CCEs from the North Atlantic margin. In 2007 similar features discovered in the Alboran Sea (Western Mediterranean) opened a new research round of CCEs. The SNSF project 200020-117928 provided the background knowledge on North Atlantic modern planktonic and benthic foraminiferal assemblages from CCEs to understand the dynamics of the fossil counterparts. SNSF Projects 200021-11694 and 200020-126367 provided the view of the Eastern Mediterranean connections. Based on the obtained results the present proposal merges the previous projects. It is now timely to investigate the foraminiferal fossil records of the CCEs to unravel their ecological importance in the past.Proposed is a high-resolution study of the ESF-EuroDiversity-MiCROSYSTEM Cores MD08-3227 and MD08-3216G recovered on the Pen-Duick Escarpment in July 2008 and spanning the upper 30 meters of sediments. For comparison, for ship time is asked in a joint venture with the Universities of Granada (Spain) and Aveiro (Portugal) to obtain a similar record from the CCEs in the Alboran Sea. Preliminary gravity cores were taken in 2008 during the cruise TTR17. They contain Holocene sediments only, the proposed cruise will retrieve the full Pleistocene sequence.The response of benthic and planktonic foraminifera to paleoenvironmental changes based on the isotopic signature of foraminiferal tests and the chemistry of the sediments (e.g., phosphorus and organic carbon) in the buried CCEs from the Gulf of Cadiz and the Alboran Sea will be interpreted in the time frame provided by AMS14C dating and bio- and isotope- stratigraphy. The research will be done in collaboration with leading European institutions such as the Royal Netherlands Institute for Sea Research (NIOZ)-Texel and the Renard Centre of Marine Geology (RCMG)-Ghent, which will provide complementary equipments and training of the PhD student on newly developed techniques, e.g., the TEX86 molecular paleotemperature proxy and the BIT-Index for flux of organic matter.The aim of this project is to obtain a multiproxy paleoceanographic scenario by achieving the following objectives:Reconstruction of the history of the western Mediterranean connection (Alboran-Cadiz system), CCE development in the last 150.000 years, and the relation to ecological, oceanographic and climate changes.Identification of regional and local factors determining similarities and differences between the Alboran Sea and the Gulf of Cadiz.Establishment of a causal link between CCEs and adjacent sediments. Testing the hypothesis of the Alboran-Cadiz gateway as an associated system also in recent times.This project also benefits of the collaboration of all members of the COCARDE Initiative aimed to foster the transfer of knowledge from university laboratories to industry and vice-versa and to encourage and stimulate the interest of the young generation to study cold-water carbonates.Dissemination plan: Within the project we plan to present our results to many local and international meetings, to submit a significant number of scientific publications to peer reviewed journals, and to collaborate in the compilation of Special Volumes and Books together with our collaborators and colleagues.