Ages and stratigraphy of lunar mare basalts: A synthesis

摘要: The chronology of lunar volcanism is based on radiometric ages determined from Apollo and Luna landing site samples, regional stratigraphic relationships, crater degradation size-frequency distribution data for units largely defined prior to the end program. Accurate estimates mare basalt are necessary place constraints duration flux volcanism, as well petrogenesis basalts their relationship thermal evolution Moon. Here, we report derived measurements exposed nearside hemisphere. Crater provide a statistically robust accurate method derive absolute model unsampled regions Moon other planetary surfaces. This paper summarizes synthesizes results our crater-counting efforts over more than 10 yr. We have dated in Oceanus Procellarum, Imbrium, Serenitatis, Tranquillitatis, Humboldtianum, Australe, Humorum, Nubium, Cognitum, Nectaris, Frigoris, numerous smaller occurrences like impact craters sinus lacus areas. Our investigations show that (1) investigated basins, was active almost 3 b.y., starting at ~3.9–4.0 b.y. ago ceasing ~1.2 ago, (2) most erupted during late Imbrian Period ~3.6–3.8 (3) significantly fewer were emplaced Eratosthenian Period, (4) possible Copernican age been found only limited areas Procellarum. confirm extend general further underscore predominance older eastern southern patches maria peripheral larger maria, contrast younger western nearside, i.e., New recent international armada spacecraft will mineralogical, geochemical, morphological, topographic, refine understanding relation petrogenetic trends evolution.