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Sanchez, A. G.

Publications and source records attributed to Sanchez, A. G..

Crater studies in the Apollo 17 region

As part of crater analysis in the Apollo 17 region, cumulative size-frequency curves were constructed, the density distribution of small craters was determined, and the effects of secondary crater clusters near the landing site were studied. The cumulative curves indicate that the old dark-mantled mare is similar in age to Apollo 11 mare, and that the adjacent young light mare of Central Serenitatis is similar in age to Apollo 15 mare. The old dark-mantled surface is markedly deficient in craters between 100 and 200 m in diameter, and the analysis suggests that this deficiency is a consequence of the old dark mantle which gives rise to an unusually thick unconsolidated layer that causes abnormally rapid degradation of small craters.

Lucchitta, B. K.↗

Geology of the Taurus-Littrow valley floor

The paper surveys the geology of the Taurus-Littrow valley which is located in a graben that is radial to Mare Serenitatis. The basalt fill is characterized; basalt extrusion in the valley continued until about 3.7 b.y. ago and was quickly followed by deposition of glass beads that formed a mantling unit of probable pyroclastic origin. The glass-bead unit in combination with the overlying regolith forms an unconsolidated surficial deposit with an average thickness of about 14 m. The components of the regolith are described. It is thought that most of the craters are part of a secondary cluster formed by projectiles from Tycho. Age estimates for the central cluster and the light mantle are presented.

Wolfe, E. W.↗