Insight into African meteorite finds: Typology, mass distribution and weathering process.

Africa is a favorable site for meteorites recovery in which the total number of meteorites represents more than 1/6 of all extra-terrestrial rocks recovered from the entire world. This work studies the classification of the African meteorite finds, their masses' distribution and their alteration grades to verify some factors influencing the weathering processes. The African population comprises an abundance of stony meteorites with high percentages of rare meteorites of the world collection: Martian meteorites (62%), Ureilites (51%), Rumuruti (59%), Lunar (47%), and HED (46%). Furthermore, throughout the last two decades, the authors noted an important increase of achondrite meteorites compared to the Australian and Antarctic collections. The mass distribution of African population shows that most of the recoveries (72%) have masses more than 100 g. It peaks at about 1 kg, compared to about 0.1 kg for the Australian collection and 0.01 kg for the Antarctic finds. On the other hand, the distribution of weathering grades (W) shows the predominant of W1 (32%) and W2 (34%) which proves a better preservation of meteorites. The factors influencing the mechanism and rate of alteration of African finds include the climate, which is the main factor, the mass, the terrestrial age and the initial porosity of the samples. • The African meteorite finds comprise significant rates of rare meteorites. • The mass distribution shows that most of recoveries (72%) have masses more than 100 g. • The variation of weathering grades shows a well preservation of meteorites in Africa. • Finds' alteration is related to climate, mass, terrestrial age and initial porosity. [ABSTRACT FROM AUTHOR]