Duggen Svend, Hoernle Kaj, van den Bogaard Paul, Rüpke Lars, Morgan Jason Phipps
GEOMAR Research Center for Marine Geosciences, Wischhofstrasse 1-3, 24148 Kiel, Germany.
Nature. 2003 Apr 10;422(6932):602-6. doi: 10.1038/nature01553.
The Messinian salinity crisis--the desiccation of the Mediterranean Sea between 5.96 and 5.33 million years (Myr) ago--was one of the most dramatic events on Earth during the Cenozoic era. It resulted from the closure of marine gateways between the Atlantic Ocean and the Mediterranean Sea, the causes of which remain enigmatic. Here we use the age and composition of volcanic rocks to reconstruct the geodynamic evolution of the westernmost Mediterranean from the Middle Miocene epoch to the Pleistocene epoch (about 12.1-0.65 Myr ago). Our data show that a marked shift in the geochemistry of mantle-derived volcanic rocks, reflecting a change from subduction-related to intraplate-type volcanism, occurred between 6.3 and 4.8 Myr ago, largely synchronous with the Messinian salinity crisis. Using a thermomechanical model, we show that westward roll back of subducted Tethys oceanic lithosphere and associated asthenospheric upwelling provides a plausible mechanism for producing the shift in magma chemistry and the necessary uplift (approximately 1 km) along the African and Iberian continental margins to close the Miocene marine gateways, thereby causing the Messinian salinity crisis.
墨西拿盐度危机——发生于596万至533万年前的地中海干涸事件——是新生代时期地球上最重大的事件之一。它是由大西洋与地中海之间海洋通道的关闭导致的，其成因至今仍是个谜。在此，我们利用火山岩的年代和成分来重建最西端地中海从中中新世到更新世（约1210万至65万年前）的地球动力学演化。我们的数据表明，地幔源火山岩地球化学的显著转变，反映了从与俯冲相关的火山作用到板内型火山作用的变化，发生在630万至480万年前，与墨西拿盐度危机大致同步。通过一个热机械模型，我们表明，俯冲的特提斯洋岩石圈向西后撤以及相关的软流圈上涌，为产生岩浆化学变化以及沿非洲和伊比利亚大陆边缘产生必要的隆升（约1千米）以关闭中新世海洋通道从而引发墨西拿盐度危机提供了一个合理的机制。
