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Geologic maps of the Descartes region of the Moon Apollo 16 pre-mission maps

D.J. Milton·C. A. Hodges
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Abstract

The evolution of the Moon’s s urface shows three successive stages (Hartmann, 1970). The earliest , from the beginning of the decipherable record to the Imbrian P eriod, was dominated by frequent large -scale impacts which produced overlapping and interfering craters and g iant multi-ringed basin with ejecta blankets. The second stage , extending through most of the Imbrian to early Eratosthenian Periods , was characterized by volcanism, producing basalt flows of the maria an vari ed materials on the terrae . The final and longest stage , extending through the greater part of the Eratosthe n ian Period and the whole of the Copernican , was one of reduced geologic activity. Major modifications of the geologic structure by large impacts of volcanism occurring only locally, although changes by small-scale impact and mass wasting affected the entire surface. The De s cartes region, in the central highlands of the Moon about 500 km southeast of the center of the lunar disk, is dominated by features of the middle st a ge and contains a n exceptionally favorable site for their study.

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D.J. Milton, C. A. Hodges. 1972. Geologic maps of the Descartes region of the Moon Apollo 16 pre-mission maps. https://doi.org/10.3133/i748

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