Bulk mineralogy of lunar crater central peaks via thermal infrared spectra from the Diviner Lunar Radiometer: A study of the Moon's crustal composition at depth

摘要: [1] The central peaks of lunar impact craters are thought to be composed uplifted material originating from varying depths the crustal column. The interpreted crystallization sequence early magma ocean resulted in an anorthositic upper crust that may become progressively more mafic as it approaches olivine-rich mantle. Emissivity spectra Lunar Reconnaissance Orbiter (LRO) Diviner Radiometer used derive wavelength location Christiansen Feature (CF), which is sensitive bulk silicate mineralogy. Here a survey CF values has been performed for 135 complex craters, providing global and regional observations heterogeneity compositions. Crustal thickness models give context preimpact depth peak its proximity crust-mantle boundary. This study identified six with potentially ultramafic compositions within their peaks. More common occurrences material, found wide variety crater peaks, show composition roughly similar mare basalt or olivine-bearing gabbro. range rest surface. Bulk mineralogy does not appear correlated origin, suggesting both lateral vertical rather than gradual transition felsic composition. It likely Moon's extensive cratering history continually overturned original crust, erasing any systematic dependence on