Photogeology: Part G: structural aspects of Imbrium sculpture

Abstract

Apollo 16 metric photographs taken at low to high Sun angles (from approximately 7° to 40°) provide the first stereographic coverage of the distinctive landforms collectively referred to as "Imbrium sculpture" (refs. 29-40 and 29-41). The sculpture consists of a series of nearly linear ridges and troughs extending radially outward for more than 1000 km from the rim of the Imbrium Basin. The sculpture is particularly well developed in the highlands southwest of the basin, where individual segments have lengths measured in tens of kilometers. THe origin of the ridges and troughs, whether by deposition and impact scoring by fluidized clouds of ejecta from the Imbrium Basin or by faulting and volcanism during and subsequent to basin formation, is controversial. Similar appearing features occur around other large basins on both the near and far sides of the Moon; thus, information leading to a better interpretation of Imbrium sculpture has significance throughout the Moon.