Academic Journal
Paleocirculation and paleoclimate conditions in the western Mediterranean basins over the last deglaciation: New insights from sediment composition variations
| العنوان: | Paleocirculation and paleoclimate conditions in the western Mediterranean basins over the last deglaciation: New insights from sediment composition variations |
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| المؤلفون: | Mesa-Fernández, J.M., Martínez-Ruiz, F., Rodrigo-Gámiz, M., Jiménez-Espejo, F.J., García-García, M. (Margarita), Sierro, F.J. (Francisco Javier) |
| بيانات النشر: | Centro Oceanográfico de Cádiz |
| سنة النشر: | 2022 |
| المجموعة: | Instituto Español de Oceanografía: e-IEO |
| مصطلحات موضوعية: | Teerrigenous and carbonate input, Alborán basin, Algero-Balearic basin, Southern Iberian margin, Organic rich layer, Holocene, Ti/Ca ratio, Heinrich event 1, Western mediterranean deep water, sediment composition, deglaciation, basins, resolution |
| الوصف: | We present a high-resolution analysis of seven marine sediment records from the western Mediterranean in a transect from the Algero-Balearic basin to the Alboran Sea, spanning the last 20 ka, to decipher the paleoenvironmental and paleoceanographic evolution of the western Mediterranean Sea. To do so, diverse elemental ratios have been used for reconstructing sediment input variations and paleo-oxygen conditions. In particular, the Ti/Ca ratio has been used to reconstruct variations in the terrigenous and carbonate fractions. However, the specific sedimentary processes controlling this ratio are still poorly understood thus, we also provide new insights for appropriate interpretations in the studied zone. Our results suggest that the Ti/Ca ratio at the suborbital scale is mostly controlled by bottom current intensity, and less influenced by marine productivity, sea level variations and fluvial and eolian inputs. Comparison of diverse records within the western Mediterranean reveals that the Ti/Ca ratio depicted a similar trend in both regions, except during the Heinrich Stadial 1 (HS1) and the Middle Holocene. The HS1 is recorded as a single-phase event in the Algero-Balearic basin, whereas three phases are recognized in the Alboran Sea basin, with a relative minimum in the Ti/Ca ratio. Conversely, during the Middle Holocene, an increase in the Ti/Ca ratio is recorded in the Alboran Sea but not in the Algero-Balearic basin, which could be related to the establishment of the Alboran gyres. Redox sensitive proxies, in particular the Mo/Al, U/Al and Mn/Al ratios, point to different phases within the Organic Rich Layer 1 (ORL1): the ORL1a (15- 11.7 ka cal BP), characterized by more reducing conditions in the Alboran Sea sediments, and the ORL1b 11.7- ~9 ka cal BP) characterized by suboxic-ferruginous conditions. The sea level transgression, the enhanced fluvial input and the shelf flooding played a key role during the ORL1 onset and demise, ncreasing the sedimentation rate in the basin and preventing the organic ... |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| تدمد: | 0921-8181 |
| Relation: | http://hdl.handle.net/10508/15652; Global and Planetary Change, 209. 2022: 103732-105000 |
| DOI: | 10.1016/j.gloplacha.2021.103732 |
| الاتاحة: | http://hdl.handle.net/10508/15652 https://doi.org/10.1016/j.gloplacha.2021.103732 |
| Rights: | openAccess |
| رقم الانضمام: | edsbas.534037C8 |
| قاعدة البيانات: | BASE |
| تدمد: | 09218181 |
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| DOI: | 10.1016/j.gloplacha.2021.103732 |