ABSTRACT
The Great Dyke of Atla Regio (GDAR) is traced for ~3700 km on Venus, as a surface graben (narrow trough) interpreted to overlie a continuous laterally-emplaced underlying mafic dyke (vertical magma-filled crack). The GDAR belongs to a giant radiating dyke swarm associated with Ozza Mons (volcano), Atla Regio plume, and was fed from a magma reservoir ~600 km south of the Ozza Mons centre. A 50-degree counter-clockwise swing of the GDAR at 1200 km from the centre is consistent with a 1200 km radius for the underlying Ozza Mons plume head, and a stress link to the 10,000 km long Parga Chasmata rift system. Our discovery of the GDAR, should spur the search for additional long continuous single dykes on Venus (and Earth), with implications for estimating plume head size, locating buffered magma reservoirs, mapping regional stress variation at a geological instant, and revealing relative ages (through cross-cutting relationships) over regional-scale distances.
ABSTRACT
Rotenone, azadirachtin, pyrethrins and copper fungicide decay curves were determined in olives and olive oil samples after experimental trials, consisting of one, two and three applications of each active ingredient, were carried out twice in 2005 and 2006. Rotenone, azadiracthin and pyrethrins were analyzed by extraction with acetonitrile and determined by liquid chromatography; copper was extracted into aqueous HCl and determined by chemical stripping. Pyrethrins were always found but in levels below the acceptable limits, whereas rotenone and copper residues always exceeded, after the pre-harvest interval, the maximum threshold allowed for olives. As regards residues in olive oil, rotenone was found in concentrations higher than those detected in olives. Copper accumulated in olives according to the number of applications, whereas, in oil, the residue was always lower than the maximum residue limit. The sensitivity of the method applied did not allow detection of azadirachtin.
