Determination of the elemental composition of rocks on Venus by Venera 13 and Venera 14 (preliminary results)

Abstract

Venera 13 and Venera 14 have determined for the first time ever the elemental composition of the Venusian rocks at the probes' landing sites. To study Venusian rocks, rolling upland and flat lowland have been chosen as the most typical of the entire planetary surface. Venera 13 landed on the rolling upland, while Venera 14 landed in the region with lower topography. The chemical composition of the rock at the Venera 13 landing site proved to be similar to the composition of potassium alkaline basalts of the earth's crust, rocks which can be found on oceanic islands and in rift zones. The chemical composition of the rock at the Venera 14 landing site is similar to that of tholeiitic basalts of the oceanic crust of the earth. The comparison of new data on the composition of Venusian rocks with the composition of the rocks of similar provinces on the earth and the moon shows that the evolution of the surface and crust of Venus was not similar to that of the earth and especially not that of the moon.

Cross-sectional profiles of Baltis Vallis channel on Venus: Reconstructions from Magellan SAR brightness data

“…Such an interpretation is supported by X-ray and γ -ray measurements undertaken by Venera and Vega landers (Surkov et al, 1983;Garvin et al, 1984;Basilevsky et al, 1985;Barsukov et al, 1986;Kargel et al, 1993), although none of these sampling locations were close to canali. If the channel-forming fluid was mafic or ultramafic lavas, the formation process would have been thermal rather than mechanical erosion because these types of lava have extremely high liquidus temperature and therefore melt the substrate effectively Gregg and Greeley, 1993;Williams-Jones et al, 1998;Snyder, 2002).…”

Hot spot heat transfer: Its application to Venus and implications to Venus and Earth

“…Further support on a more local scale for the scenario of crustal thickening by volcanic activity is provided by the radar identification of shield volcanoes on Beta Regio[Saunders and Malin, 1977], one of the areas of Venus primarily in the elevation range 6053-6055 km, and by the suggestion of a basaltic surface composition near Beta Regio from Venera geochemical results[Surkov et al, 1983]. Some topography may be due to volcanic construction, but the gravity analyses indicate primar-ily isostatic compensation for the high elevations, although this result is nonunique.…”

Planetary Tectonics and Volcanism: The Inner Solar System

“…They are interpreted to be volcanic plains, composed of thinly layered lava flows; this interpretation is supported by images of the Venusian surface taken by the Venera landers (e.g., Garvin et al, 1984;Surkov et al, 1983). Plains are typically deformed by wrinkle ridges, graben, lineaments, and/or polygonal lineaments.…”