Lunar Landscapes

Speaker: Bill Ambrose - Senior Research Scientist - Bureau of Economic Geology The Moon has an amazing variety of landscapes and surface features easily observed with modest-sized telescopes and which have recently been imaged by the Lunar Reconnaissance Orbiter and the Chang’e 5 lander. Many are related to impacts—basins ringed by majestic mountains (some greater than 15,000-ft tall), long valleys gouged out by ground-hugging ejecta, and craters in all shapes and sizes. However, a number of other intriguing features on the Moon are volcanic in origin, such as small (less than 20-km) lava domes. The Moon also contains structural features such as rift valleys and fault scarps, as well as curiosities that defy explanation—mysteriously and randomly aligned crater chains, swirls with remnant paleomagnetism, and smooth and uncratered patches of terrain that may represent recent lunar degassing events. Unlike the surface of the Earth, which is relatively young because of continuing resurfacing from tectonic activity and erosion, over 80% of the Moon’s surface is older than 3 billion years old. It therefore retains a record of the violent, early history of the solar system. William A. Ambrose is a Senior Research Scientist (retired) at the Bureau of Economic Geology, the University of Texas at Austin, where he holds a Master of Arts degree in geological sciences. He is currently Co-Chair of the Astrogeology Committee of the American Association of Petroleum Geologists (AAPG). His research interests in planetary geology include energy resources in the Solar System and lunar geology, with an emphasis on crater morphology and secondary craters associated with large impact basins. Bill has given numerous presentations on planetary science at meetings of the LPSC (Lunar and Planetary Science Conference), GSA (Geological Society of America), and AAPG. He is co-editor of GSA Special Paper 477, “Recent Advances and Current Research Issues in Lunar Stratigraphy” and AAPG Memoir 101 “Energy Resources for Human Settlement in the Solar System and Earth’s Future in Space”.