Moon-Earth: global basaltic effusions, their different ages, common chemical trends(alkalinity, iron content)
Gennady G. Kochemasov
IGEM of the Russian Academy of Sciences, 35 Staromonetny, 119017 Moscow,kochem.36@mail.ru

Global basaltic covers are very characteristic phenomena in the inner solar system. Basaltic
effusions of different ages and compositions originated in asthenospheric layers of theplanetary mantles. To heat and melt some parts of the mantle, a part of enormous mechanicalenergy of orbiting cosmic bodies was transferred to the heat energy.
“Orbits make structures” – a main point of the new wave planetology based on one
important property of the Keplerian elliptical planetary orbits [2, 3] . The ellipticity implies
periodical changes of accelerations and, thus, orbital forces structuring cosmic bodies. TheEarth and the Moon sharing the same circumsolar orbit have similar main structural features.
Among them there are terrestrial Oceans and lunar Basins. The most obvious are two tectonic
triads: Pacific Ocean – Malay Archipelago – Indian Ocean on Earth and Procellarum Basin –Mare Orientale – SPA Basin on the Moon. The planetary depressions of both bodies arecovered with basalts, but basaltic effusions are drastically different in age: the AR on Moonand Mz-Cz on Earth. These ages well correlate with the bodies masses. The more massive andinert Earth has heated and melted mantle much later (The Newton’s law of inertia). Energy ofmovement transfers to the heat energy.
The both cosmic bodies, as well as the rest of them, are tectonically dichotomous. Theirsubsided hemispheres, for keeping angular momentum of hemispheres equal, are filled withdense basaltic material. But times of the fillings are significantly different.
The Earth-Moon system expands with time, that is increases its angular momentum. A
natural response to it is in slowing down rotation of both bodies diminishing their angularmomentum (action - opposite action). Diminishing momenta are compensated by melting anduplifting to surfaces dense basaltic material. But on the Moon it happened much earlier(4.5-3 billion years ago) because of diminished inertia of the small mass satellite. At muchlarger and massive with large inertia Earth this process was significantly “delayed” intime.(Mz-Cz). Earth is 81 times more massive than Moon. (3-4.5 billions) : 81 = 37-55
million years. According to this calculation, a “peak” of the basaltic reaction of Earth, fillingin by basalts the oceanic depressions is in the boundary of Mesozoic and Cenozoic [3]].
Despite of enormous age differences between lunar and terrestrial basaltic covers (billionsof years!) some common chemical shift of their compositions is notable and significant. Letus compare Procellarum Basin and Pacific Ocean basalts. The oldest parts of their covers
occur mainly in the West of Procellarum (KREEP) and SW of the Pacific (Ontong JavaPlateau – the largest LIP of Earth). Potassium, phosphorus, rare earths, thorium enrich theolder lunar KREEP basalts. The older terrestrial oceanic Ontong Java basalts (Cretaceous ageabout 122 mln. y) also show “KREEP trend”. They belong to E-MORBs and have elevatedvalues of potassium, lithium, chlorine, REE, thorium. Elevated Fe/Mg (and siderofileplatinum group elements) also is in Ontong Java basalts [1]. All these chemical peculiarities
distinguish them from the younger N-MORBs of other parts of the Pacific Ocean (EPR, forexample). As all considered basalt melts of both bodies originate in asthenopheres, the older
parts of these melts derive from relatively earlier “cool” asthenosphere. It means that only
easily melted alkali and iron rich parts were involved in the process. Later on, significantly
heated asthenospheres produced enormous volumes of chemically different (less alkaline andmore magnesian) basalts. In this sense, rather impressive is a comparison of the lunar iron andthorium geochemical maps stressing coincidence of their anomalies in the Procellarum
KREEP terrain area (Fig. 1, 2).
The considered time development of basaltic magmatism could be paralleled with thedevelopment of alkaline terrestrial magmatism. Its earlier older parts often are more alkaline
than later Cenozoic parts. Famous large agpaitic massifs are mainly Proterozoic-Paleozoic inage. Again, early “cold” asthenosphere produces more easily melted relatively small alkalineparts than the later “hot” asthenosphere making large volumes of deeply melted moremagnesian less alkaline ones.
References:[1] Ely J.C. and Neal C.R. (2003) Using platinum-group elements to investigate the origin ofthe Ontong Java Plateau, SW Pacific // Chemical Geology, v. 196, 235-25[2] Kochemasov G.G. (2016) The Moon and Phobos: specific responses of two satellites
moving off and nearer their respective planets // DPS 48/EPSC 11, Pasadena, Oct. 16-21,
2016, Bulletin of the American Astronomical Society, 2016, vol. 48, # 7, p. 175, Abstract
318.08, Session 318: Formation and Evolution of Planets and Satellites Posters.
[3] Kochemasov G.G. (2017) New planetology and geology: tectonic identity and principal
difference of terrestrial oceans and lunar basins // New Concepts in Global Tectonics (NCGT)
Journal, 2017, V. 5, # 1, p 131-133.

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