The U.S. research ship Maurice Ewing left Mexico Tuesday after a string of controversies caused by the vessel’s sonic-pulse experiments and its collision with a coral reef.
In its first public explanation of the February 14 accident in which the ship ran aground on a coral reef, Columbia University’s Lamont-Doherty Earth Observatory, which operates the vessel, said the crew had relied on apparently flawed or misleading navigational charts.
“The ship’s charts indicated adequate water depth at the location of the grounding,” the observatory said in a press statement. “There was no damage to the vessel.”
Mexican authorities had claimed the reef was clearly marked on maps, and had called the accident — which damage about 20 square yards (meters) of underwater rock formations and about 10 square yards (meters) of coral — “inexplicable,” considering the ship’s state-of-the-art equipment.
On Monday the observatory paid a fine of 2,221,720 pesos ($200,000, euro150,000) for damaging the reef, located about 30 miles (48 kms) off the Yucatan peninsula.
“The research vessel Maurice Ewing sailed from Progresso, Mexico, Tuesday, after completing a research mission that began on January 12th,” according to the press statement.
The observatory said the international research team had completed its five-week research mission examining the Chicxulub crater to learn about the asteroid impact that might have led to the extinction of the dinosaurs.
The team included scientists from Mexico’s National Autonomous University, the University of Texas Institute of Geophysics, and the Universities of Cambridge and London in the United Kingdom.
Environmentalists opposed the ship’s activities, arguing that the seismic technology could harm sea life including whales, which use sound waves to communicate.