在弥赛尼盐度危机之后,地中海的灾难性洪水
D Garcia-Castellanos1, F Estrada, I Jiménez-Munt
1Institut de Ciències de la Terra Jaume Almera, CSIC, Solé i Sabarís s/n, Barcelona, Spain.
Nature
|December 17, 2009
概括
5,330万年前,桑克伦洪水迅速重新填充了地中海. 新的分析揭示了洪水形成的直布罗陀海峡通道,这表明快速补充事件持续数月至两年.
科学领域:
- 地质地质地质地质地质地
- 海洋学 海洋学 海洋学
- 古气候学 古气候学
背景情况:
- 地中海在弥赛尼盐度危机 (约5.6万年前) 期间干.
- 桑克伦洪水 (约5.33万年前) 迅速通过直布罗陀海峡重新填补了该盆地.
- 洪水的特征,包括它的突然性和演变,仍然不太清楚.
研究的目的:
- 调查直布罗陀海峡内的侵蚀特征.
- 为了确定穿过海峡的切口通道的形态和起源.
- 为了估计Zanclean洪水的持续时间和排放量.
主要方法:
- 在直布罗陀海峡的钻井和地震数据分析.
- 在山地河流中验证的切口模型的应用.
- 对一条长达200公里的运河进行了形态分析.
主要成果:
- 切割道连续穿过直布罗陀海峡.
- 道形态与洪水侵蚀一致,而不是之前的河流侵蚀.
- 估计的峰值排放量为~10^8 m^3 s^-1和切口率>0.4 m/天.
- 90%的水被转移在几个月到两年的时间内.
结论:
- 桑克伦洪水是一个极其突如其来的事件.
- 地中海海平面上升的峰值超过了每天10米.
- 这些发现完善了我们对赞克伦洪水的动态和影响的理解.
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