The Mediterranean Sea dried out partly or near completely during the Messinian around six million years ago (the "Messinian salinity crisis" or MSC). However, the relative role that tectonic processes and sea-level changes had, as triggers for restriction and isolation of the Mediterranean Sea from the open ocean, is still under debate. G. Jimnez-Moreno and colleagues present a detailed pollen, dinoflagellate cyst (dinocyst), and magnetic susceptibility analysis of a marine sedimentary sequence of late Neogene (between about 7.3 and 5.2 million years ago) from the Montemayor-1 core (lower Guadalquivir Basin, southwestern Spain). Their results show that significant paired vegetation and sea-level changes occurred during the Messinian, likely triggered by orbital-scale climate change. Important cooling events and corresponding glacio-eustatic sea-level drops are observed in this study at ca. 5.95 and 5.75 million years ago coinciding with the timing and duration of oxygen isotopic events TG32 and TG22-20 recorded in marine sediments worldwide. It is generally accepted that the onset of the MSC began about 5.96 million years ago; this study suggests that the restriction of the Mediterranean could have been triggered, at least in part, by a strong glacio-eustatic sea-level drop linked to a climate cooling occurring at the time of the MSC initiation.
Fault kinematics and surface deformation across a releasing bend during the 2010 MW 7.1 Darfield, New Zealand, earthquake revealed by differential LiDAR and cadastral surveying
Brendan Duffy et al., Dept. of Geological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand. Posted online 21 Dec. 2012; http://dx.doi.org/1
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Geological Society of America