Geochemistry of sediments cores in the Mediterranean Sea

We investigated five time-equivalent core sections (180-110 kyr BP) from the Balearic Sea (Menorca Rise), the easternmost Levantine Basin and southwest, south, and southeast of Crete to reconstruct spatial patterns of productivity during deposition of sapropels S5 and S6 in the Mediterranean Sea. Our indicators are Ba, total organic carbon and carbonate contents. We found no indications of Ba remobilization within the investigated core intervals, and used the accumulation rate of biogenic Ba to compute paleoproductivity. Maximum surface water productivity (up to 350 g C/m2/yr) was found during deposition of S5 (isotope stage 5e) but pronounced spatial variability is evident. Coeval sediment intervals in the Balearic Sea show very little productivity change, suggesting that chemical and biological environments in the eastern and western Mediterranean basins were decoupled in this interval. […]

本研究对来自巴利阿里海（梅诺卡升高地）、最东端的黎凡特盆地以及克里特岛西南、南及东南地区的五个时间等效核心层段（180-110千年前）进行了调查，以重建地中海海盆中沉积物S5和S6期间生产力空间分布模式。本研究的指标包括钡含量、总有机碳和碳酸盐含量。在调查的核心层段内，未发现钡的再活化迹象，并利用生物成因钡的积累速率计算了古生产力。在S5沉积期间（同位素阶段5e），发现了最高表层水生产力（高达350克碳/平方米/年），但空间变异性显著。巴利阿里海的同期沉积层段生产力变化极小，这表明在这一时期，东、西地中海盆地的化学和生物环境相互独立。