Detection of groundwater conduits in limestones with gravity surveys: Datafrom the area of the Chicxulub Impact Crater, Yucatan Peninsula, Mexico

Small negative gravity anomalies are found in gravity data from along the n orthwestern shoreline of the Yucatan Peninsula These anomalies are shown to be due to elongate, shallow anomalous porosity zones in-the Tertiary carbo nates. These zones are caused primarily by groundwater solution and are pre sently active conduits for groundwater flow. The association of these small gravity anomalies with known topographic and structural features of the ar ea, which partially overlies the Chicxulub Impact crater, indicates their d evelopment was influenced by structures, faults and/or fractures, within th e Tertiary and pre-Tertiary carbonates.