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Large earthquakes sometimes activate volcanoes both in the near field as well as in the far field. One possible explanation is that shaking may increase the mobility of the volcanic gases stored in magma reservoirs and conduits.Here experimentally and theoretically we investigate how sloshing, the oscillatory motion of fluids contained in a shaking tank, may affect the presence and stability of bubbles and foams, with important implications for magma conduits and reservoirs. We adopt this concept from engineering: severe earthquakes are known to induce sloshing and damage petroleum tanks. Sloshing occurs in a partially filled tank or a fully filled tank with density-stratified fluids. These conditions are met at open summit conduits or at sealed magma reservoirs where a bubbly magma layer overlays a newly injected denser magma layer. We conducted sloshing experiments by shaking a rectangular tank partially filled with liquids, bubbly fluids (foams) and fully filled with density-stratified fluids; i.e., a foam layer overlying a liquid layer. In experiments with foams, we find that

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The pilot hole (VB) of the German Continental Deep Drilling Program (KTB) was drilled to a depth of 4000 m, where large amounts of free fluids were met. The KTB-VB 4000 m fluid can be related to either Mesozoic seawater or formation water from Permo-Carboniferous sedimentary rocks of the Weiden embayment. During the Upper Cretaceous uplift of the Bohemian Massif both fluids could have passed organic-rich Triassic to Carboniferous formations of the Weiden embayment before invading the uplifted and fractured basement rocks of Devonian amphibolites and metagabbros, where the chemical composition of the fluids was changed by albitization, adularization, and chloritization. Results of chemical mass balances for both sources are presented. In order to concentrate the formation water from the Weiden embayment significant amphibolitization has to be assumed. During a 1-year pumping test the chemical composition of the 4000 m fluids remained constant. The accuracy of chemical analyses is critically reviewed. An improved preconcentration method of rare earth elements and yttrium in high-Ca-bearing saline fluids is described.