Abstract:

The large number of meteorites from Antarctica and the desert areas of Australia,Africa and North America changed the previous chondrite classification in recent years.The number of well established groups has increased from 9 to 13(EH,EL,H,L,LL,R,CI,CR,CH,CM,CO,CV and CK) and three new carbonaceous chondrite grouplets have been proposed. There are remarkable differences among chondrite groups in petrographic, mineralogical, chemical and O isotopic characteristics. We suggested that 13 chondrite groups can be divided into carbonaceous chondrite family consisting of CI CR CH,CM CO and CV CK clans and enstitate ordinary chondrite family consisting of EH EL, H L LL and R clans. The carbonaceous chondrites are charcterized by high oxidation state.The enstitate ordinary chondrite family formed near the Sun and in the inner solar system.