Mineralogical and geochemical features of sulfide chimneys from the 49°39′E hydrothermal field on the Southwest Indian Ridge and their geological inferences

© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chinese Science Bulletin 56 (2011): 2828-2838, doi:10.1007/s11434-011-4619-4.During January–May in 2007, the Chinese research cruise DY115-19 discovered an active hydrothermal field at 49°39′E/37°47′S on the ultraslow spreading Southwest Indian Ridge (SWIR). This was also the first active hydrothermal field found along an ultraslow-spreading ridge. We analyzed mineralogical, textural and geochemical compositions of the sulfide chimneys obtained from the 49°39′E field. Chimney samples show a concentric mineral zone around the fluid channel. The mineral assemblages of the interiors consist mainly of chalcopyrite, with pyrite and sphalerite as minor constitunets. In the intermediate portion, pyrite becomes the dominant mineral, with chalcopyrite and sphalerite as minor constitunets. For the outer wall, the majority of minerals are pyrite and sphalerite, with few chalcopyrite. Towards the outer margin of the chimney wall, the mineral grains become small and irregular in shape gradually, while minerals within interstices are abundant. These features are similar to those chimney edifices found on the East Pacific Rise and Mid-Atlantic Ridge. The average contents of Cu, Fe and Zn in our chimney samples were 2.83 wt%, 45.6 wt% and 3.28 wt%, respectively. The average Au and Ag contents were up to 2.0 ppm and 70.2 ppm respectively, higher than the massive sulfides from most hydrothermal fields along mid-ocean ridge. The rare earth elements geochemistry of the sulfide chimneys show a pattern distinctive from the sulfides recovered from typical hydrothermal fields along sediment-starved mid-ocean ridge, with the enrichment of light rare earth elements but the weak, mostly negative, Eu anomaly. This is attributed to the distinct mineralization environment or fluid compositions in this area.This work was supported by the China Ocean Mineral Resources Research and Development Association Program (DY115- 02-1-01) and the State Oceanic Administration Youth Science Fund (2010318)

Seismic structure across the rift valley of the Mid-Atlantic Ridge at 23°20′ (MARK area): Implications for crustal accretion processes at slow spreading ridges

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Moving forward : In search of synergy across diverse views on the role of physical movement in design for stem education

Inspired by the current embodiment turn in the cognitive sciences, researchers of STEM teaching and learning have been evaluating implications of this turn for educational theory and practice. But whereas design researchers have been developing domain-specific theories that implicate the role of physical movement in conceptual learning, the field has yet to agree on a conceptually coherent and empirically validated framework for leveraging and shaping students’ capacity for physical movement as a socio–cognitive educational resource. This symposium thus convenes to ask, “What is movement in relation to concepts such that we can design for learning?” To stimulate discussion, we highlight an emerging tension across a set of innovative technological designs with respect to the framing question of whether students should discover an activity’s targeted movement forms themselves or that these forms should be cued directly. Our content domains span mathematics (proportions, geometry), physics, chemistry, and ecological system dynamics (predator–prey, bees)

Moving forward : In search of synergy across diverse views on the role of physical movement in design for stem education

Inspired by the current embodiment turn in the cognitive sciences, researchers of STEM teaching and learning have been evaluating implications of this turn for educational theory and practice. But whereas design researchers have been developing domain-specific theories that implicate the role of physical movement in conceptual learning, the field has yet to agree on a conceptually coherent and empirically validated framework for leveraging and shaping students’ capacity for physical movement as a socio–cognitive educational resource. This symposium thus convenes to ask, “What is movement in relation to concepts such that we can design for learning?” To stimulate discussion, we highlight an emerging tension across a set of innovative technological designs with respect to the framing question of whether students should discover an activity’s targeted movement forms themselves or that these forms should be cued directly. Our content domains span mathematics (proportions, geometry), physics, chemistry, and ecological system dynamics (predator–prey, bees)