Wind-driven reorganization of coarse clasts on the surface of Mars
Jon D. Pelletier et al., Department of Geosciences, University of Arizona, Gould-Simpson Building, 1040 East Fourth Street, Tucson, Arizona 85721-0077, USA. Pages 55-58.
Individual rocks in some areas of Mars are regularly spaced. Here, Pelletier et al. show that rocks can move around on the surface of Mars and organize into a regular pattern due to the action of the wind, without being picked up. This occurs because of the way that air flows around the rocks, and the resulting pattern of erosion of the underlying sandy surface. Repeated cycles of erosion around the rocks and subsequent rolling cause them to move and organize spatially.
Evidence for focused magmatic accretion at segment centers from lateral dike injections captured beneath the Red Sea rift in Afar
Derek Keir et al., School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK. Pages 59-62.
Keir et al. have captured the emplacement of two new vertical sheets of volcanic rock in Ethiopia, where Arabia and Africa are separating to create a new ocean. Observations of earthquakes and the motion of Earth's surface show that each new sheet of volcanic rock is about 10 km long, about 2 m wide, and created rapidly over approximately hour-long time scales. The new sheets of rock are initially molten, and travel horizontally in the upper 10 km of the Earth from a magma reservoir beneath a major volcano. The results of Keir et al. suggest that repeated emplacement of similar volcanic structures allows continents to split apart and new oceans to form.
Uplift and magma intrusion at Long Valley caldera from InSAR and gravity measurements
Pietro Tizzani et al., CNR-Istituto per il Rilevamento Elettromagnetico dell'Ambiente, Via Dio
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Geological Society of America