Stratigraphic studies: Part B: geologic setting of the dark mantling material in the Taurus-Littrow region of the Moon

A dark-colored surficial deposit covers lowlands and highlands along the southeastern margin of the Serenitatis basin. Sampling of this material was a major exploration objective of the Apollo 17 mission. Since completion of the mission, the dark mantle has been the subject of considerable controversy, inasmuch as no obvious stratified deposit was found in the landing area. Yet the material can clearly be seen in the vicinity on orbital photographs, and it is distinctly darker than all the dark mare surrounding the Serenitatis basin (Fig. 29-11). Furthermore, the geologic setting as shown by Apollo 15 and 17 panoramic photographs shows critical relations that must be accounted for in future interpretations.