A Geomorfologia das Estruturas de Impacto na Superfície Lunar

Abstract

Lunar geology is currently divided into five main periods, which mark the stages of formation of the lunar surface over time. Each of these periods has characteristic structures — some newer, preserving the originality of their formation, and others older, which present only remnants of their original structure or are even completely absent from the surface. These structures make up the lunar geomorphology as we know it today. This research work aims to study the structures of each of the lunar geological periods, categorized according to the “release of the digital unified global geologic map of the moon at 1:5,000,000-scale” that served as the basis for the research. This survey provides the most recent and complete lunar geological map available. Based on this, a representative structure from each lunar geological period was selected for a detailed geomorphological study and, subsequently, for a comparison between the structures, within the possibilities and available data. For this, satellite images of the lunar surface, obtained from Digital Elevation Models (DEM), were used. The two main DEM sources used were: “Lua LRO LOLA – SELENE Kaguya TC Shaded Relief Merge 60N60S 59m v1” and “Lua LRO LOLA – SELENE Kaguya TC DEM Merge 60N60S 59m v1”, the latter being the shaded version. These images, however, do not allow a complete study of the entire lunar surface, as they do not cover the poles, being limited to the area between latitudes -60° and +60°, and longitudes from -180° to +180°. Thus, the analysis area was restricted according to the coverage of the available DEMs. With these data, it was possible to compose detailed maps of the lunar surface and, together with the geological map, apply GIS (Geographic Information System) techniques to develop this research. Throughout the research, it is possible to notice that the structures present degradation when compared, where the most recent formations are better preserved and have a better definition compared to the oldest ones that present a faster level of degradation. It is worth mentioning that the purpose of this work is not to present a conclusive result, but rather to carry out a structural geomorphological analysis of the chosen formations and a brief comparison between them, based on the results acquired throughout the research.