Persistent scatterer interferometry analysis of the embankment failure of a red mud reservoir using ENVISAT ASAR data

On October 4, 2010, the embankment of No. 10 red mud—waste product during bauxite refining—reservoir of MAL Co. Ltd. alumina plant collapsed. Around 700 000 cubic meter of alkaline slurry with 11–13 pH value flooded three nearby settlements. Ten people were killed, 123 wounded, and about 350 houses were damaged or became uninhabitable in one of the biggest industrial and ecological catastrophe in modern history of Hungary. Synthetic aperture radar interferometry (InSAR) is the only geodetic technique that can reveal the past stability and motion history of the broken reservoir. We performed a persistent scatterer InSAR (PSI) analysis to contribute to the better understanding of the disaster. The key question we address in this study is whether there were signs prior to October 4th event which may have prognosticated the disaster. The PSI results could reveal if the dam was stable in the past without prior signs of the failure or there were definite indications of deformation before the collapse and proper monitoring of motions could have highlighted the risk and the disaster may have been prevented. This is a rare event and its PSI study is unique and may be critical in understanding it and helping to prevent other similar occurrences.     

格陵兰冰心中的矿物粉尘记录

矿物粉尘在当今气候研究中发挥着重要的作用。矿物粉尘气溶胶具有的发射性质使其直接影响着大气圈的辐射平衡。矿物粉尘也以多种间接方式积极参与了气候活动,其中包括成为云层凝聚中心来决定云盖层的规模和特征以及可能控制着遥远的营养贫瘠的大洋与大陆地区的原始生物生产力。     

Geochronology of a composite granitoid pluton: a high-precision ID-TIMS U–Pb zircon study of the Variscan Karkonosze Granite (SW Poland)

Resolving time differences between successive magmatic pulses in composite granitoid plutons is often a difficult task. High-precision CA-ID-TIMS zircon ages obtained from such a pluton, the Variscan Karkonosze Granite (NE part of the Bohemian Massif), provide evidence that the crystallization of the two main granite facies, porphyritic and equigranular, happened between 312.5 ± 0.3 and 312.2 ± 0.3 Ma, thus unresolvable at the 0.08–0.1 % precision level of a single ²⁰⁶Pb/²³⁸U age. This finding is at odds with most other previous dating attempts and asks for a re-evaluation of the previous scattered geochronological data. The main reasons for the scatter of the earlier dates obtained by various techniques can include analytical causes, the presence of older inheritance and disturbance of the U–Pb isotopic system, due to zircon metamictization (enhanced by high-U content in zircon) or late- and post-magmatic alteration.