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The surroundings of Viking 1 Lander (1)
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Commenti originali:"These pictures show a knobby exposure of bedrock broken by vertical fractures. Some of the protuberances are so deeply eroded that they almost form detached boulders. Indeed, we believe that many of the boulders at this site form by this mechanism of "in situ" weathering. The area of bedrock is more clearly delineated. Horizontal rock surfaces have been swept clear of sediment. The fact that this rock weathers in a different fashion than the rocks displayed in other frames suggest a compositional difference between the two exposures of bedrock. However, both rock types are believed to be representative of volcanic lavas that inundated the entire region early in Martian history.
Finding bedrock at this landing site was a surprise. Among other things, it indicates that Martian geologic history is more complex than Lunar history. If a thick layer of ejected deposits once covered this region, it has been subsequently removed by wind, water, or maybe even ice in the form of glaciers".
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