Eric Walker added The Sinkhole That Swallowed a Mexican Farm | The New Yorker to Sinkholes

Eric Walker added A Giant Sinkhole Just Opened Up in Chile to Sinkholes

Eric Walker added Sinkholes in Siberia and The Sinkhole That Swallowed a Mexican Farm | The New Yorker and A Giant Sinkhole Just Opened Up in Chile to Sinkholes, and added Sinkholes to Geology

Eric Walker added a number of links to Sinkholes in Siberia, and added Sinkholes in Siberia to Sinkholes and Siberia

Eric Walker added a number of topics and a number of links to Geology, and added Geology to Science, engineering, mathematics and the humanities