Geological and thermodynamic aspects of lunar rocks

Geological and themodynamic spects of lunar rocks are studied. Several basic problems of lunar geology are examined with the main purpose of assembling the regional information needed to establish a list of possible lunar mineral deposits and to postulate on the origin of the Moon with emphasis on probable composition. Important problems related to the structural pattern of the Moon are discussed. A special study is devoted to the Vredefort Ring structure (South Africa), which has been recently interpreted as convincing example of asteroidal impacts on the Earth. The distribution of craterlets is analyzed by statistical methods, in order to establish whether these typical lunar features are originated by volcanic activity or impact phenomena. The thermodynamic aspects are an attempt to provide a broad reconnaissance of the stability of rock-forming mineral oxides with respect to pressure and temperature. Free energy temperature diagrams were constructed to cover the behavior of various petrological oxides between 0 K and 5000 K.