CHICXULUB MULTIRING IMPACT BASIN - SIZE AND OTHER CHARACTERISTICS DERIVED FROM GRAVITY ANALYSIS

The buried Chicxulub impact structure in Mexico, which is linked to th e Cretaceous-Tertiary (K-T) boundary layer, may be significantly large r than previously suspected. Reprocessed gravity data over Northern Yu catan reveal three major rings and parts of a fourth ring, spaced simi larly to those observed at multiring impact basins on other planets. T he outer ring, probably corresponding to the basin's topographic rim, is almost 300 kilometers in diameter, indicating that Chicxulub may be one of the largest impact structures produced in the inner solar syst em since the period of early bombardment ended nearly 4 billion years ago.