[1] GPS observations along three profiles across the Ethiopian Rift and Afar triple junction record differences in the length scale over which extension is accommodated. In the Afar region, where the mantle lithosphere is nearly or entirely absent, measurable extension occurs over $175 km; in the northern Ethiopian Rift, where the mantle lithosphere is anomalously thin and hot, extensional strain occurs over $85 km, extending beyond the structural rift valley; in the southern Ethiopian Rift, where the mantle lithosphere approaches standard continental thickness, extensional strain occurs over <10 km. This trend of increasingly distributed deformation contrasts with the standard model where continental rifts become mid-ocean spreading centers through strain localization.

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Reverse electron transfer, in which an electron is transferred uphill from a redox couple with a higher standard reduction potential in one phase to another redox couple having a lower standard reduction potential in a second immiscible phase, is demonstrated using the system TCNQ (in 1,2-dichloroethane)/ferrocyanide (in water). The driving force for the reverse electron transfer is the presence of appropriate potential-determining ions that govern the interfacial potential difference, which in turn determines the position of equilibrium in the two-phase redox reaction. The occurrence of reverse electron transfer was monitored by scanning electrochemical microscopy.

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