Abstract
A Monte-Carlo technique has been used to investigate the orbital evolution of asteroidal collision debris produced interior to 2.6 AU. It is found that there are two regions primarily responsible for production of Earth-crossing meteoritic material and Apollo objects. The region adjacent to the 3:1 jovian commensurability resonance (2.5 AU) is unique in providing material in the required quantity and orbital distribution of the ordinary chondrites. This region should also supply a comparable preatmospheric flux of carbonaceous meteorites. The innermost asteroid belt (2.17-2.25 AU), via the v6secular resonance, provides a fluxca.9% that of the ordinary chondrites, and appears to be the strongest candidate for the basaltic achondrite source region. It is unlikely that a significant number of meteorites originate beyond 2.6 AU. It is speculated that enstatite achondrites are derived from the Hungaria region, interior to the main belt, and that iron and stony-iron meteorites originate from many main-belt sources interior to 2.6 AU.